1/*  Part of JPL -- SWI-Prolog/Java interface
    2
    3    Author:        Paul Singleton, Fred Dushin and Jan Wielemaker
    4    E-mail:        paul@jbgb.com
    5    WWW:           http://www.swi-prolog.org
    6    Copyright (c)  2004-2020, Paul Singleton
    7    All rights reserved.
    8
    9    Redistribution and use in source and binary forms, with or without
   10    modification, are permitted provided that the following conditions
   11    are met:
   12
   13    1. Redistributions of source code must retain the above copyright
   14       notice, this list of conditions and the following disclaimer.
   15
   16    2. Redistributions in binary form must reproduce the above copyright
   17       notice, this list of conditions and the following disclaimer in
   18       the documentation and/or other materials provided with the
   19       distribution.
   20
   21    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   22    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   23    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   24    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   25    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   26    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   27    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   28    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   29    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   30    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   31    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   32    POSSIBILITY OF SUCH DAMAGE.
   33*/
   34
   35:- module(jpl,
   36    [   jpl_get_default_jvm_opts/1,
   37        jpl_set_default_jvm_opts/1,
   38        jpl_get_actual_jvm_opts/1,
   39        jpl_pl_lib_version/1,
   40        jpl_c_lib_version/1,
   41        jpl_pl_syntax/1,
   42        jpl_new/3,
   43        jpl_call/4,
   44        jpl_get/3,
   45        jpl_set/3,
   46        jpl_servlet_byref/3,
   47        jpl_servlet_byval/3,
   48        jpl_class_to_classname/2,
   49        jpl_class_to_type/2,
   50        jpl_classname_to_class/2,
   51        jpl_classname_to_type/2, % name does not reflect that it deals with entity names
   52        jpl_datum_to_type/2,
   53        jpl_entityname_to_type/2, % new alias for jpl_classname_to_type/2
   54        jpl_false/1,
   55        jpl_is_class/1,
   56        jpl_is_false/1,
   57        jpl_is_null/1,
   58        jpl_is_object/1,
   59        jpl_is_object_type/1,
   60        jpl_is_ref/1,
   61        jpl_is_true/1,
   62        jpl_is_type/1,
   63        jpl_is_void/1,
   64        jpl_null/1,
   65        jpl_object_to_class/2,
   66        jpl_object_to_type/2,
   67        jpl_primitive_type/1,
   68        jpl_ref_to_type/2,
   69        jpl_true/1,
   70        jpl_type_to_class/2,
   71        jpl_type_to_classname/2, % name does not reflect that it deals with entity names
   72        jpl_type_to_entityname/2, % new alias for jpl_type_to_classname/2
   73        jpl_void/1,
   74        jpl_array_to_length/2,
   75        jpl_array_to_list/2,
   76        jpl_datums_to_array/2,
   77        jpl_enumeration_element/2,
   78        jpl_enumeration_to_list/2,
   79        jpl_hashtable_pair/2,
   80        jpl_iterator_element/2,
   81        jpl_list_to_array/2,
   82        jpl_terms_to_array/2,
   83        jpl_array_to_terms/2,
   84        jpl_map_element/2,
   85        jpl_set_element/2
   86   ]).   87:- autoload(library(apply),[maplist/2]).   88:- autoload(library(debug),[debugging/1,debug/3]).   89:- autoload(library(lists),
   90	    [member/2,nth0/3,nth1/3,append/3,flatten/2,select/3]).   91:- autoload(library(shlib),[load_foreign_library/1]).

  100% suppress debugging this library
  101:- set_prolog_flag(generate_debug_info, false).

 jpl_new(+X, +Params, -V) is det

X can be:

• an atomic classname, e.g. 'java.lang.String'
• or an atomic descriptor, e.g. '[I' or 'Ljava.lang.String;'
• or a suitable type, i.e. any class(_,_) or array(_), e.g. class([java,util],['Date'])

If X is an object (non-array) type or descriptor and Params is a list of values or references, then V is the result of an invocation of that type's most specifically-typed constructor to whose respective formal parameters the actual Params are assignable (and assigned).

If X is an array type or descriptor and Params is a list of values or references, each of which is (independently) assignable to the array element type, then V is a new array of as many elements as Params has members, initialised with the respective members of Params.

If X is an array type or descriptor and Params is a non-negative integer N, then V is a new array of that type, with N elements, each initialised to Java's appropriate default value for the type.

If V is literally {Term} then we attempt to convert a new org.jpl7.Term instance to a corresponding term; this is of little obvious use here, but is consistent with jpl_call/4 and jpl_get/3.

  132jpl_new(X, Params, V) :-
  133    (   var(X)
  134    ->  throwme(jpl_new,x_is_var)
  135    ;   jpl_is_type(X)                  % NB Should check for "instantiable type"? Also accepts "double" for example.
  136    ->  Type = X
  137    ;   atom(X)                         % an atom not captured by jpl_is_type/1 e.g. 'java.lang.String', '[L', even "void"
  138    ->  (   jpl_entityname_to_type(X, Type)
  139        ->  true
  140        ;   throwme(jpl_new,x_not_classname(X))
  141        )
  142    ;   throwme(jpl_new,x_not_instantiable(X))
  143    ),
  144    jpl_new_1(Type, Params, Vx),
  145    (   nonvar(V),
  146        V = {Term}  % yucky way of requesting Term->term conversion
  147    ->  (   jni_jref_to_term(Vx, TermX)    % fails if Vx is not a JRef to a org.jpl7.Term
  148        ->  Term = TermX
  149        ;   throwme(jpl_new,not_a_jpl_term(Vx))
  150        )
  151    ;   V = Vx
  152    ).

 jpl_new_1(+Tx, +Params, -Vx)

(serves only jpl_new/3)

Tx can be a class(_,_) or array(_) type.

Params must be a proper list of constructor parameters.

At exit, Vx is bound to a JPL reference to a new, initialised instance of Tx

  165jpl_new_1(class(Ps,Cs), Params, Vx) :-
  166    !,                                      % green (see below)
  167    Tx = class(Ps,Cs),
  168    (   var(Params)
  169    ->  throwme(jpl_new_class,params_is_var)
  170    ;   \+ is_list(Params)
  171    ->  throwme(jpl_new_class,params_is_not_list(Params))
  172    ;   true
  173    ),
  174    length(Params, A),          % the "arity" of the required constructor
  175    jpl_type_to_class(Tx, Cx),  % throws Java exception if class is not found
  176    N = '<init>',               % JNI's constructor naming convention for GetMethodID()
  177    Tr = void,                  % all constructors have this return "type"
  178    findall(
  179        z3(I,MID,Tfps),
  180        jpl_method_spec(Tx, I, N, A, _Mods, MID, Tr, Tfps), % cached
  181        Z3s
  182    ),
  183    (   Z3s == []               % no constructors which require the given qty of parameters?
  184    ->  (   jpl_call(Cx, isInterface, [], @(true))
  185        ->  throwme(jpl_new_class,class_is_interface(Tx))
  186        ;   throwme(jpl_new_class,class_without_constructor(Tx,A))
  187        )
  188    ;   (   catch(
  189                jpl_datums_to_types(Params, Taps),  % infer actual parameter types
  190                % 2020-07-21: make catcher's 1st context arg an "anonvar" instead of a overspecified predicate indicator
  191                error(type_error(acyclic,Te),context(_,Msg)),
  192                throwme(jpl_new_class,acyclic(Te,Msg)) % rethrow
  193            )
  194        ->  true
  195        ;   throwme(jpl_new_class,bad_jpl_datum(Params))
  196        ),
  197        findall(
  198            z3(I,MID,Tfps),                 % select constructors to which actual parameters are assignable
  199            (   member(z3(I,MID,Tfps), Z3s),
  200                jpl_types_fit_types(Taps, Tfps) % assignability test: actual parameter types "fit" formal parameter types?
  201            ),
  202            Z3sA
  203        ),
  204        (   Z3sA == []                      % no type-assignable constructors?
  205        ->  (   Z3s = [_]
  206            ->  throwme(jpl_new_class,single_constructor_mismatch(Tx/A))
  207            ;   throwme(jpl_new_class,any_constructor_mismatch(Params))
  208            )
  209        ;   Z3sA = [z3(I,MID,Tfps)]
  210        ->  true
  211        ;   jpl_z3s_to_most_specific_z3(Z3sA, z3(I,MID,Tfps))
  212        ->  true
  213        ;   throwme(jpl_new_class,constructor_multimatch(Params))
  214        )
  215    ),
  216    catch(
  217        jNewObject(Cx, MID, Tfps, Params, Vx),
  218        error(java_exception(_), 'java.lang.InstantiationException'),
  219        throwme(jpl_new_class,class_is_abstract(Tx)) % Rethrow
  220    ),
  221    jpl_cache_type_of_ref(Tx, Vx).          % since we know it
  222
  223jpl_new_1(array(T), Params, Vx) :-
  224    !,
  225    (   var(Params)
  226    ->  throwme(jpl_new_array,params_is_var)
  227    ;   integer(Params)         % integer I -> array[0..I-1] of default values
  228    ->  (   Params >= 0
  229        ->  Len is Params
  230        ;   throwme(jpl_new_array,params_is_negative(Params))
  231        )
  232    ;   is_list(Params)     % [V1,..VN] -> array[0..N-1] of respective values
  233    ->  length(Params, Len)
  234    ),
  235    jpl_new_array(T, Len, Vx), % NB may throw out-of-memory exception
  236    (   nth0(I, Params, Param),     % nmember fails silently when Params is integer
  237        jpl_set(Vx, I, Param),
  238        fail
  239    ;   true
  240    ),
  241    jpl_cache_type_of_ref(array(T), Vx).   % since we know it
  242
  243jpl_new_1(T, _Params, _Vx) :-       % doomed attempt to create new primitive type instance (formerly a dubious completist feature :-)
  244    jpl_primitive_type(T),
  245    !,
  246    throwme(jpl_new_primitive,primitive_type_requested(T)).
  247  % (   var(Params)
  248  % ->  throwme(jpl_new_primitive,params_is_var)
  249  % ;   Params == []
  250  % ->  jpl_primitive_type_default_value(T, Vx)
  251  % ;   Params = [Param]
  252  % ->  jpl_primitive_type_term_to_value(T, Param, Vx)
  253  % ;   throwme(jpl_new_primitive,params_is_bad(Params))
  254  % ).
  255
  256jpl_new_1(T, _, _) :- throwme(jpl_new_catchall,catchall(T)).

 jpl_new_array(+ElementType, +Length, -NewArray) is det

binds NewArray to a jref to a newly created Java array of ElementType and Length

  263jpl_new_array(boolean, Len, A) :-
  264    jNewBooleanArray(Len, A).
  265jpl_new_array(byte, Len, A) :-
  266    jNewByteArray(Len, A).
  267jpl_new_array(char, Len, A) :-
  268    jNewCharArray(Len, A).
  269jpl_new_array(short, Len, A) :-
  270    jNewShortArray(Len, A).
  271jpl_new_array(int, Len, A) :-
  272    jNewIntArray(Len, A).
  273jpl_new_array(long, Len, A) :-
  274    jNewLongArray(Len, A).
  275jpl_new_array(float, Len, A) :-
  276    jNewFloatArray(Len, A).
  277jpl_new_array(double, Len, A) :-
  278    jNewDoubleArray(Len, A).
  279jpl_new_array(array(T), Len, A) :-
  280    jpl_type_to_class(array(T), C),
  281    jNewObjectArray(Len, C, @(null), A).        % initialise each element to null
  282jpl_new_array(class(Ps,Cs), Len, A) :-
  283    jpl_type_to_class(class(Ps,Cs), C),
  284    jNewObjectArray(Len, C, @(null), A).

 jpl_call(+X, +MethodName:atom, +Params:list(datum), -Result:datum) is det

X should be either

• an object reference, e.g. <jref>(1552320) (for static or instance methods)
• or a classname, e.g. 'java.util.Date' (for static methods only)
• or a descriptor, e.g. 'Ljava.util.Date;' (for static methods only)
• or type, e.g. class([java,util],['Date']) (for static methods only)

MethodName should be a method name (as an atom) (may involve dynamic overload resolution based on inferred types of params)

Params should be a proper list (perhaps empty) of suitable actual parameters for the named method.

The class or object may have several methods with the given name; JPL will resolve (per call) to the most appropriate method based on the quantity and inferred types of Params. This resolution mimics the corresponding static resolution performed by Java compilers.

Finally, an attempt will be made to unify Result with the method's returned value, or with @(void) (the compound term with name @ and argument void) if it has none.

  306jpl_call(X, Mspec, Params, R) :-
  307    (   jpl_object_to_type(X, Type)         % the usual case (goal fails safely if X is var or rubbish)
  308    ->  Obj = X,
  309        Kind = instance
  310    ;   var(X)
  311    ->  throwme(jpl_call,arg1_is_var)
  312    ;   atom(X)
  313    ->  (   jpl_entityname_to_type(X, Type)     % does this attempt to load the class?
  314        ->  (   jpl_type_to_class(Type, ClassObj)
  315            ->  Kind = static
  316            ;   throwme(jpl_call,no_such_class(X))
  317            )
  318        ;   throwme(jpl_call,arg1_is_bad(X))
  319        )
  320    ;   X = class(_,_)
  321    ->  Type = X,
  322        jpl_type_to_class(Type, ClassObj),
  323        Kind = static
  324    ;   X = array(_)
  325    ->  throwme(jpl_call,arg1_is_array(X))
  326    ;   throwme(jpl_call,arg1_is_bad(X))
  327    ),
  328    (   atom(Mspec)                 % the usual case, i.e. a method name
  329    ->  true
  330    ;   var(Mspec)
  331    ->  throwme(jpl_call,mspec_is_var)
  332    ;   throwme(jpl_call,mspec_is_bad(Mspec))
  333    ),
  334    (   is_list(Params)
  335    ->  (   catch(
  336                jpl_datums_to_types(Params, Taps),
  337                % 2020-07-21: make catcher's 1st context arg an "anonvar" instead of a overspecified predicate indicator
  338                error(type_error(acyclic,Te),context(_,Msg)),
  339                throwme(jpl_call,acyclic(Te,Msg)) % rethrow
  340            )
  341        ->  true
  342
  343        ;   throwme(jpl_call,nonconvertible_params(Params))
  344        ),
  345        length(Params, A)
  346    ;   var(Params)
  347    ->  throwme(jpl_call,arg3_is_var)
  348    ;   throwme(jpl_call,arg3_is_bad(Params))
  349    ),
  350    (   Kind == instance
  351    ->  jpl_call_instance(Type, Obj, Mspec, Params, Taps, A, Rx)
  352    ;   jpl_call_static(Type, ClassObj, Mspec, Params, Taps, A, Rx)
  353    ),
  354    (   nonvar(R),
  355        R = {Term}  % yucky way of requesting Term->term conversion
  356    ->  (   jni_jref_to_term(Rx, TermX)    % fails if Rx isn't a JRef to a org.jpl7.Term
  357        ->  Term = TermX
  358        ;   throwme(jpl_call,not_a_jpl_term(Rx))
  359        )
  360    ;   R = Rx
  361    ).

 jpl_call_instance(+ObjectType, +Object, +MethodName, +Params, +ActualParamTypes, +Arity, -Result)

calls the MethodName-d method (instance or static) of Object (which is of ObjectType), which most specifically applies to Params, which we have found to be (respectively) of ActualParamTypes, and of which there are Arity, yielding Result.

  371jpl_call_instance(Type, Obj, Mname, Params, Taps, A, Rx) :-
  372    findall(                    % get remaining details of all accessible methods of Obj's class (as denoted by Type)
  373        z5(I,Mods,MID,Tr,Tfps),
  374        jpl_method_spec(Type, I, Mname, A, Mods, MID, Tr, Tfps),
  375        Z5s
  376    ),
  377    (   Z5s = []
  378    ->  throwme(jpl_call_instance,no_such_method(Mname/A))
  379    ;   findall(
  380            z5(I,Mods,MID,Tr,Tfps),             % those to which Params is assignable
  381            (   member(z5(I,Mods,MID,Tr,Tfps), Z5s),
  382                jpl_types_fit_types(Taps, Tfps) % assignability test: actual param types "fit" formal param types
  383            ),
  384            Z5sA                                % Params-assignable methods
  385        ),
  386        (   Z5sA == []
  387        ->  throwme(jpl_call_instance,param_not_assignable(Params))
  388        ;   Z5sA = [z5(I,Mods,MID,Tr,Tfps)]
  389        ->  true                                % exactly one applicable method
  390        ;   jpl_z5s_to_most_specific_z5(Z5sA, z5(I,Mods,MID,Tr,Tfps))
  391        ->  true                                % exactly one most-specific applicable method
  392        ;   throwme(jpl_call_instance,multiple_most_specific(Mname/Params))
  393        )
  394    ),
  395    (   member(static, Mods)                                        % if the chosen method is static
  396    ->  jpl_object_to_class(Obj, ClassObj),                         % get a java.lang.Class instance which personifies Obj's class
  397        jpl_call_static_method(Tr, ClassObj, MID, Tfps, Params, Rx) % call static method w.r.t. associated Class object
  398    ;   jpl_call_instance_method(Tr, Obj, MID, Tfps, Params, Rx)    % else call (non-static) method w.r.t. object itself
  399    ).

 jpl_call_static(+ClassType, +ClassObject, +MethodName, +Params, +ActualParamTypes, +Arity, -Result)

calls the MethodName-d static method of the class (which is of ClassType, and which is represented by the java.lang.Class instance ClassObject) which most specifically applies to Params, which we have found to be (respectively) of ActualParamTypes, and of which there are Arity, yielding Result.

  410jpl_call_static(Type, ClassObj, Mname, Params, Taps, A, Rx) :-
  411    findall(                    % get all accessible static methods of the class denoted by Type and ClassObj
  412        z5(I,Mods,MID,Tr,Tfps),
  413        (   jpl_method_spec(Type, I, Mname, A, Mods, MID, Tr, Tfps),
  414            member(static, Mods)
  415        ),
  416        Z5s
  417    ),
  418    (   Z5s = []
  419    ->  throwme(jpl_call_static,no_such_method(Mname))
  420    ;   findall(
  421            z5(I,Mods,MID,Tr,Tfps),
  422            (   member(z5(I,Mods,MID,Tr,Tfps), Z5s),
  423                jpl_types_fit_types(Taps, Tfps) % assignability test: actual param types "fit" formal param types
  424            ),
  425            Z5sA                                % Params-assignable methods
  426        ),
  427        (   Z5sA == []
  428        ->  throwme(jpl_call_static,param_not_assignable(Params))
  429        ;   Z5sA = [z5(I,Mods,MID,Tr,Tfps)]
  430        ->  true                % exactly one applicable method
  431        ;   jpl_z5s_to_most_specific_z5(Z5sA, z5(I,Mods,MID,Tr,Tfps))
  432        ->  true                % exactly one most-specific applicable method
  433        ;   throwme(jpl_call_instance,multiple_most_specific(Mname/Params))
  434        )
  435    ),
  436    jpl_call_static_method(Tr, ClassObj, MID, Tfps, Params, Rx).

 jpl_call_instance_method(+Type, +ClassObject, +MethodID, +FormalParamTypes, +Params, -Result)

  441jpl_call_instance_method(void, Class, MID, Tfps, Ps, R) :-
  442    jCallVoidMethod(Class, MID, Tfps, Ps),
  443    jpl_void(R).
  444jpl_call_instance_method(boolean, Class, MID, Tfps, Ps, R) :-
  445    jCallBooleanMethod(Class, MID, Tfps, Ps, R).
  446jpl_call_instance_method(byte, Class, MID, Tfps, Ps, R) :-
  447    jCallByteMethod(Class, MID, Tfps, Ps, R).
  448jpl_call_instance_method(char, Class, MID, Tfps, Ps, R) :-
  449    jCallCharMethod(Class, MID, Tfps, Ps, R).
  450jpl_call_instance_method(short, Class, MID, Tfps, Ps, R) :-
  451    jCallShortMethod(Class, MID, Tfps, Ps, R).
  452jpl_call_instance_method(int, Class, MID, Tfps, Ps, R) :-
  453    jCallIntMethod(Class, MID, Tfps, Ps, R).
  454jpl_call_instance_method(long, Class, MID, Tfps, Ps, R) :-
  455    jCallLongMethod(Class, MID, Tfps, Ps, R).
  456jpl_call_instance_method(float, Class, MID, Tfps, Ps, R) :-
  457    jCallFloatMethod(Class, MID, Tfps, Ps, R).
  458jpl_call_instance_method(double, Class, MID, Tfps, Ps, R) :-
  459    jCallDoubleMethod(Class, MID, Tfps, Ps, R).
  460jpl_call_instance_method(array(_), Class, MID, Tfps, Ps, R) :-
  461    jCallObjectMethod(Class, MID, Tfps, Ps, R).
  462jpl_call_instance_method(class(_,_), Class, MID, Tfps, Ps, R) :-
  463    jCallObjectMethod(Class, MID, Tfps, Ps, R).

 jpl_call_static_method(+Type, +ClassObject, +MethodID, +FormalParamTypes, +Params, -Result)

  468jpl_call_static_method(void, Class, MID, Tfps, Ps, R) :-
  469    jCallStaticVoidMethod(Class, MID, Tfps, Ps),
  470    jpl_void(R).
  471jpl_call_static_method(boolean, Class, MID, Tfps, Ps, R) :-
  472    jCallStaticBooleanMethod(Class, MID, Tfps, Ps, R).
  473jpl_call_static_method(byte, Class, MID, Tfps, Ps, R) :-
  474    jCallStaticByteMethod(Class, MID, Tfps, Ps, R).
  475jpl_call_static_method(char, Class, MID, Tfps, Ps, R) :-
  476    jCallStaticCharMethod(Class, MID, Tfps, Ps, R).
  477jpl_call_static_method(short, Class, MID, Tfps, Ps, R) :-
  478    jCallStaticShortMethod(Class, MID, Tfps, Ps, R).
  479jpl_call_static_method(int, Class, MID, Tfps, Ps, R) :-
  480    jCallStaticIntMethod(Class, MID, Tfps, Ps, R).
  481jpl_call_static_method(long, Class, MID, Tfps, Ps, R) :-
  482    jCallStaticLongMethod(Class, MID, Tfps, Ps, R).
  483jpl_call_static_method(float, Class, MID, Tfps, Ps, R) :-
  484    jCallStaticFloatMethod(Class, MID, Tfps, Ps, R).
  485jpl_call_static_method(double, Class, MID, Tfps, Ps, R) :-
  486    jCallStaticDoubleMethod(Class, MID, Tfps, Ps, R).
  487jpl_call_static_method(array(_), Class, MID, Tfps, Ps, R) :-
  488    jCallStaticObjectMethod(Class, MID, Tfps, Ps, R).
  489jpl_call_static_method(class(_,_), Class, MID, Tfps, Ps, R) :-
  490    jCallStaticObjectMethod(Class, MID, Tfps, Ps, R).

 jpl_get(+X, +Fspec, -V:datum) is det

X can be

• a classname
• or a descriptor
• or an (object or array) type (for static fields)
• or a non-array object (for static and non-static fields)
• or an array (for 'length' pseudo field, or indexed element retrieval)

Fspec can be

• an atomic field name
• or an integral array index (to get an element from an array)
• or a pair I-J of integers (to get a subrange of an array).

Finally, an attempt will be made to unify V with the retrieved value or object reference.

Examples

jpl_get('java.awt.Cursor', 'NE_RESIZE_CURSOR', Q).
Q = 7.

jpl_new(array(class([java,lang],['String'])), [for,while,do,if,then,else,try,catch,finally], A),
jpl_get(A, 3-5, B).
B = [if, then, else].

  522jpl_get(X, Fspec, V) :-
  523    (   jpl_object_to_type(X, Type)
  524    ->  Obj = X,
  525        jpl_get_instance(Type, Type, Obj, Fspec, Vx)   % pass Type twice for FAI
  526    ;   var(X)
  527    ->  throwme(jpl_get,arg1_is_var)
  528    ;   jpl_is_type(X)          % e.g. class([java,lang],['String']), array(int)
  529    ->  Type = X,
  530        (   jpl_type_to_class(Type, ClassObj)
  531        ->  jpl_get_static(Type, ClassObj, Fspec, Vx)
  532        ;   throwme(jpl_get,named_class_not_found(Type))
  533        )
  534    ;   atom(X)
  535    ->  (   jpl_entityname_to_type(X, Type)     % does this attempt to load the class? (NO!)
  536        ->  (   jpl_type_to_class(Type, ClassObj)
  537            ->  jpl_get_static(Type, ClassObj, Fspec, Vx)
  538            ;   throwme(jpl_get,named_class_not_found(Type))
  539            )
  540        ;   throwme(jpl_get,arg1_is_bad(X))
  541        )
  542    ;   throwme(jpl_get,arg1_is_bad_2(X))
  543    ),
  544    (   nonvar(V),
  545        V = {Term}  % yucky way of requesting Term->term conversion
  546    ->  (   jni_jref_to_term(Vx, TermX)    % fails if Rx is not a JRef to a org.jpl7.Term
  547        ->  Term = TermX
  548        ;   throwme(jpl_get,not_a_jpl_term(X))
  549        )
  550    ;   V = Vx
  551    ).

 jpl_get_static(+Type:type, +ClassObject:jref, +FieldName:atom, -Value:datum) is det

ClassObject is an instance of java.lang.Class which represents the same class as Type; Value (Vx below) is guaranteed unbound on entry, and will, before exit, be unified with the retrieved value

  563jpl_get_static(Type, ClassObj, Fname, Vx) :-
  564    (   atom(Fname)             % assume it's a field name
  565    ->  true
  566    ;   var(Fname)
  567    ->  throwme(jpl_get_static,arg2_is_var)
  568    ;   throwme(jpl_get_static,arg2_is_bad(Fname))
  569    ),
  570  % get static fields of the denoted class
  571    findall(
  572        z4(I,Mods,FID,Tf),
  573        (   jpl_field_spec(Type, I, Fname, Mods, FID, Tf),
  574            member(static, Mods)
  575        ),
  576        Z4s
  577    ),
  578    (   Z4s = []
  579    ->  throwme(jpl_get_static,no_such_field(Fname))
  580    ;   Z4s = [z4(I,_Mods,FID,Tf)]
  581    ->  jpl_get_static_field(Tf, ClassObj, FID, Vx)
  582    ;   throwme(jpl_get_static,multiple_fields(Fname))
  583    ).

 jpl_get_instance(+Type, +Type, +Object, +FieldSpecifier, -Value) is det

  589jpl_get_instance(class(_,_), Type, Obj, Fname, Vx) :-
  590    (   atom(Fname)                 % the usual case
  591    ->  true
  592    ;   var(Fname)
  593    ->  throwme(jpl_get_instance,arg2_is_var)
  594    ;   throwme(jpl_get_instance,arg2_is_bad(Fname))
  595    ),
  596    findall(
  597        z4(I,Mods,FID,Tf),
  598        jpl_field_spec(Type, I, Fname, Mods, FID, Tf),
  599        Z4s
  600    ),
  601    (   Z4s = []
  602    ->  throwme(jpl_get_instance,no_such_field(Fname))
  603    ;   Z4s = [z4(I,Mods,FID,Tf)]
  604    ->  (   member(static, Mods)
  605        ->  jpl_object_to_class(Obj, ClassObj),
  606            jpl_get_static_field(Tf, ClassObj, FID, Vx)
  607        ;   jpl_get_instance_field(Tf, Obj, FID, Vx)
  608        )
  609    ;   throwme(jpl_get_instance,multiple_fields(Fname))
  610    ).
  611
  612
  613jpl_get_instance(array(ElementType), _, Array, Fspec, Vx) :-
  614    (   var(Fspec)
  615    ->  throwme(jpl_get_instance_array,arg2_is_var)
  616    ;   integer(Fspec)
  617    ->  (   Fspec < 0       % lo bound check
  618        ->  throwme(jpl_get_instance_array,arg2_is_bad(Fspec))
  619        ;   jGetArrayLength(Array, Len),
  620            Fspec >= Len    % hi bound check
  621        ->  throwme(jpl_get_instance_array,arg2_is_too_large(Fspec))
  622        ;   jpl_get_array_element(ElementType, Array, Fspec, Vx)
  623        )
  624    ;   Fspec = N-M     % NB should we support e.g. 3-2 -> [] ?
  625    ->  (   integer(N),
  626            integer(M)
  627        ->  (   N >= 0,
  628                M >= N
  629            ->  jGetArrayLength(Array, Len),
  630                (   N >= Len
  631                ->  throwme(jpl_get_instance_array,bad_range_low(N-M))
  632                ;   M >= Len
  633                ->  throwme(jpl_get_instance_array,bad_range_high(N-M))
  634                ;   jpl_get_array_elements(ElementType, Array, N, M, Vx)
  635                )
  636            ;   throwme(jpl_get_instance_array,bad_range_pair_values(N-M))
  637            )
  638        ;   throwme(jpl_get_instance_array,bad_range_pair_types(N-M))
  639        )
  640    ;   atom(Fspec)
  641    ->  (   Fspec == length             % special-case for this solitary array "method"
  642        ->  jGetArrayLength(Array, Vx)
  643        ;   throwme(jpl_get_instance_array,no_such_field(Fspec))
  644        )
  645    ;   throwme(jpl_get_instance_array,wrong_spec(Fspec))
  646    ).

 jpl_get_array_element(+ElementType:type, +Array:jref, +Index, -Vc) is det

Array is a JPL reference to a Java array of ElementType; Vc is (unified with a JPL repn of) its Index-th (numbered from 0) element Java values are now converted to Prolog terms within foreign code

To be done

- more of this could be done within foreign code

  659jpl_get_array_element(Type, Array, Index, Vc) :-
  660    (   (   Type = class(_,_)
  661        ;   Type = array(_)
  662        )
  663    ->  jGetObjectArrayElement(Array, Index, Vr)
  664    ;   jpl_primitive_type(Type)
  665    ->  jni_type_to_xput_code(Type, Xc),
  666        jni_alloc_buffer(Xc, 1, Bp),        % one-element buf for a Type
  667        jpl_get_primitive_array_region(Type, Array, Index, 1, Bp),
  668        jni_fetch_buffer_value(Bp, 0, Vr, Xc),    % zero-th element
  669        jni_free_buffer(Bp)
  670    ),
  671    Vr = Vc.    % redundant since Vc is always (?) unbound at call

 jpl_get_array_elements(+ElementType, +Array, +N, +M, -Vs)

serves only jpl_get_instance/5

Vs will always be unbound on entry

  680jpl_get_array_elements(ElementType, Array, N, M, Vs) :-
  681    (   (   ElementType = class(_,_)
  682        ;   ElementType = array(_)
  683        )
  684    ->  jpl_get_object_array_elements(Array, N, M, Vs)
  685    ;   jpl_get_primitive_array_elements(ElementType, Array, N, M, Vs)
  686    ).
  687
  688
  689jpl_get_instance_field(boolean, Obj, FieldID, V) :-
  690    jGetBooleanField(Obj, FieldID, V).
  691jpl_get_instance_field(byte, Obj, FieldID, V) :-
  692    jGetByteField(Obj, FieldID, V).
  693jpl_get_instance_field(char, Obj, FieldID, V) :-
  694    jGetCharField(Obj, FieldID, V).
  695jpl_get_instance_field(short, Obj, FieldID, V) :-
  696    jGetShortField(Obj, FieldID, V).
  697jpl_get_instance_field(int, Obj, FieldID, V) :-
  698    jGetIntField(Obj, FieldID, V).
  699jpl_get_instance_field(long, Obj, FieldID, V) :-
  700    jGetLongField(Obj, FieldID, V).
  701jpl_get_instance_field(float, Obj, FieldID, V) :-
  702    jGetFloatField(Obj, FieldID, V).
  703jpl_get_instance_field(double, Obj, FieldID, V) :-
  704    jGetDoubleField(Obj, FieldID, V).
  705jpl_get_instance_field(class(_,_), Obj, FieldID, V) :-
  706    jGetObjectField(Obj, FieldID, V).
  707jpl_get_instance_field(array(_), Obj, FieldID, V) :-
  708    jGetObjectField(Obj, FieldID, V).

 jpl_get_object_array_elements(+Array, +LoIndex, +HiIndex, -Vcs) is det

Array should be a (zero-based) array of some object (array or non-array) type; LoIndex is an integer, 0 =< LoIndex < length(Array); HiIndex is an integer, LoIndex-1 =< HiIndex < length(Array); at call, Vcs will be unbound; at exit, Vcs will be a list of (references to) the array's elements [LoIndex..HiIndex] inclusive

  720jpl_get_object_array_elements(Array, Lo, Hi, Vcs) :-
  721    (   Lo =< Hi
  722    ->  Vcs = [Vc|Vcs2],
  723        jGetObjectArrayElement(Array, Lo, Vc),
  724        Next is Lo+1,
  725        jpl_get_object_array_elements(Array, Next, Hi, Vcs2)
  726    ;   Vcs = []
  727    ).

 jpl_get_primitive_array_elements(+ElementType, +Array, +LoIndex, +HiIndex, -Vcs) is det

Array should be a (zero-based) Java array of (primitive) ElementType; Vcs should be unbound on entry, and on exit will be a list of (JPL representations of the values of) the elements [LoIndex..HiIndex] inclusive

  737jpl_get_primitive_array_elements(ElementType, Array, Lo, Hi, Vcs) :-
  738    Size is Hi-Lo+1,
  739    (   Size == 0
  740    ->  Vcs = []
  741    ;   jni_type_to_xput_code(ElementType, Xc),
  742        jni_alloc_buffer(Xc, Size, Bp),
  743        jpl_get_primitive_array_region(ElementType, Array, Lo, Size, Bp),
  744        jpl_primitive_buffer_to_array(ElementType, Xc, Bp, 0, Size, Vcs),
  745        jni_free_buffer(Bp)
  746    ).
  747
  748
  749jpl_get_primitive_array_region(boolean, Array, Lo, S, I) :-
  750    jGetBooleanArrayRegion(Array, Lo, S, jbuf(I,boolean)).
  751jpl_get_primitive_array_region(byte, Array, Lo, S, I) :-
  752    jGetByteArrayRegion(Array, Lo, S, jbuf(I,byte)).
  753jpl_get_primitive_array_region(char, Array, Lo, S, I) :-
  754    jGetCharArrayRegion(Array, Lo, S, jbuf(I,char)).
  755jpl_get_primitive_array_region(short, Array, Lo, S, I) :-
  756    jGetShortArrayRegion(Array, Lo, S, jbuf(I,short)).
  757jpl_get_primitive_array_region(int, Array, Lo, S, I) :-
  758    jGetIntArrayRegion(Array, Lo, S, jbuf(I,int)).
  759jpl_get_primitive_array_region(long, Array, Lo, S, I) :-
  760    jGetLongArrayRegion(Array, Lo, S, jbuf(I,long)).
  761jpl_get_primitive_array_region(float, Array, Lo, S, I) :-
  762    jGetFloatArrayRegion(Array, Lo, S, jbuf(I,float)).
  763jpl_get_primitive_array_region(double, Array, Lo, S, I) :-
  764    jGetDoubleArrayRegion(Array, Lo, S, jbuf(I,double)).
  765
  766
  767jpl_get_static_field(boolean, Array, FieldID, V) :-
  768    jGetStaticBooleanField(Array, FieldID, V).
  769jpl_get_static_field(byte, Array, FieldID, V) :-
  770    jGetStaticByteField(Array, FieldID, V).
  771jpl_get_static_field(char, Array, FieldID, V) :-
  772    jGetStaticCharField(Array, FieldID, V).
  773jpl_get_static_field(short, Array, FieldID, V) :-
  774    jGetStaticShortField(Array, FieldID, V).
  775jpl_get_static_field(int, Array, FieldID, V) :-
  776    jGetStaticIntField(Array, FieldID, V).
  777jpl_get_static_field(long, Array, FieldID, V) :-
  778    jGetStaticLongField(Array, FieldID, V).
  779jpl_get_static_field(float, Array, FieldID, V) :-
  780    jGetStaticFloatField(Array, FieldID, V).
  781jpl_get_static_field(double, Array, FieldID, V) :-
  782    jGetStaticDoubleField(Array, FieldID, V).
  783jpl_get_static_field(class(_,_), Array, FieldID, V) :-
  784    jGetStaticObjectField(Array, FieldID, V).
  785jpl_get_static_field(array(_), Array, FieldID, V) :-
  786    jGetStaticObjectField(Array, FieldID, V).

 jpl_set(+X, +Fspec, +V) is det

sets the Fspec-th field of (class or object) X to value V iff it is assignable

X can be

• a class instance (for static or non-static fields)
• or an array (for indexed element or subrange assignment)
• or a classname, or a class(_,_) or array(_) type (for static fields)
• but not a String (no fields to retrieve)

Fspec can be

• an atomic field name (overloading through shadowing has yet to be handled properly)
• or an array index I (X must be an array object: V is assigned to X[I])
• or a pair I-J of integers (X must be an array object, V must be a list of values: successive members of V are assigned to X[I..J])

V must be a suitable value or object.

  806jpl_set(X, Fspec, V) :-
  807    (   jpl_object_to_type(X, Type)         % the usual case (test is safe if X is var or rubbish)
  808    ->  Obj = X,
  809        catch(
  810            jpl_set_instance(Type, Type, Obj, Fspec, V),    % first 'Type' is for FAI
  811            % 2020-07-21: make catcher's 1st context arg an "anonvar" instead of a overspecified predicate indicator
  812            error(type_error(acyclic,Te),context(_,Msg)),
  813            throwme(jpl_set,acyclic(Te,Msg)) % rethrow
  814        )
  815    ;   var(X)
  816    ->  throwme(jpl_set,arg1_is_var)
  817    ;   (   atom(X)
  818        ->  (   jpl_entityname_to_type(X, Type)          % it's a classname or descriptor...
  819            ->  true
  820            ;   throwme(jpl_set,classname_does_not_resolve(X))
  821            )
  822        ;   (   X = class(_,_)                          % it's a class type...
  823            ;   X = array(_)                            % ...or an array type
  824            )
  825        ->  Type = X
  826        ),
  827        (   jpl_type_to_class(Type, ClassObj)      % ...whose Class object is available
  828        ->  true
  829        ;   throwme(jpl_set,named_class_not_found(Type))
  830        )
  831    ->  catch(
  832            jpl_set_static(Type, ClassObj, Fspec, V),
  833            % 2020-07-21: make catcher's 1st context arg an "anonvar" instead of a overspecified predicate indicator
  834            error(type_error(acyclic,Te),context(_,Msg)),
  835            throwme(jpl_set,acyclic(Te,Msg)) % rethrow
  836        )
  837    ;   throwme(jpl_set,arg1_is_bad(X))
  838    ).

 jpl_set_instance(+Type, +Type, +ObjectReference, +FieldName, +Value) is det

ObjectReference is a JPL reference to a Java object of the class denoted by Type (which is passed twice for first agument indexing);

FieldName should name a public, non-final (static or non-static) field of this object, but could be anything, and is validated here;

Value should be assignable to the named field, but could be anything, and is validated here

  851jpl_set_instance(class(_,_), Type, Obj, Fname, V) :-    % a non-array object
  852    (   atom(Fname)                 % the usual case
  853    ->  true
  854    ;   var(Fname)
  855    ->  throwme(jpl_set_instance_class,arg2_is_var)
  856    ;   throwme(jpl_set_instance_class,arg2_is_bad(Fname))
  857    ),
  858    findall(
  859        z4(I,Mods,FID,Tf),
  860        jpl_field_spec(Type, I, Fname, Mods, FID, Tf),  % public fields of class denoted by Type
  861        Z4s
  862    ),
  863    (   Z4s = []
  864    ->  throwme(jpl_set_instance_class,no_such_field(Fname))
  865    ;   Z4s = [z4(I,Mods,FID,Tf)]
  866    ->  (   member(final, Mods)
  867        ->  throwme(jpl_set_instance_class,field_is_final(Fname))
  868        ;   jpl_datum_to_type(V, Tv)
  869        ->  (   jpl_type_fits_type(Tv, Tf)
  870            ->  (   member(static, Mods)
  871                ->  jpl_object_to_class(Obj, ClassObj),
  872                    jpl_set_static_field(Tf, ClassObj, FID, V)
  873                ;   jpl_set_instance_field(Tf, Obj, FID, V)         % oughta be jpl_set_instance_field?
  874                )
  875            ;   throwme(jpl_set_instance_class,incompatible_value(Tf,V))
  876            )
  877        ;   throwme(jpl_set_instance_class,arg3_is_bad(V))
  878        )
  879    ;   throwme(jpl_set_instance_class,multiple_fields(Fname))  % 'existence'? or some other sort of error maybe?
  880    ).
  881
  882
  883
  884jpl_set_instance(array(Type), _, Obj, Fspec, V) :-
  885    (   is_list(V)                  % a list of array element values
  886    ->  Vs = V
  887    ;   var(V)
  888    ->  throwme(jpl_set_instance_array,arg3_is_var)
  889    ;   Vs = [V]                    % a single array element value
  890    ),
  891    length(Vs, Iv),
  892    (   var(Fspec)
  893    ->  throwme(jpl_set_instance_array,arg2_is_var)
  894    ;   integer(Fspec)          % single-element assignment
  895    ->  (   Fspec < 0
  896        ->  throwme(jpl_set_instance_array,arg2_is_bad(Fspec))
  897        ;   Iv is 1
  898        ->  N is Fspec
  899        ;   Iv is 0
  900        ->  throwme(jpl_set_instance_array,no_values(Fspec,Vs))
  901        ;   throwme(jpl_set_instance_array,more_than_one_value(Fspec,Vs))
  902        )
  903    ;   Fspec = N-M             % element-sequence assignment
  904    ->  (   integer(N),
  905            integer(M)
  906        ->  (   N >= 0,
  907                Size is (M-N)+1,
  908                Size >= 0
  909            ->  (   Size == Iv
  910                ->  true
  911                ;   Size < Iv
  912                ->  throwme(jpl_set_instance_array,too_few_values(N-M,Vs))
  913                ;   throwme(jpl_set_instance_array,too_many_values(N-M,Vs))
  914                )
  915            ;   throwme(jpl_set_instance_array,bad_range_pair_values(N-M))
  916            )
  917        ;   throwme(jpl_set_instance_array,bad_range_pair_types(N-M))
  918        )
  919    ;   atom(Fspec)
  920    ->  (   Fspec == length
  921        ->  throwme(jpl_set_instance_array,cannot_assign_to_final_field)
  922        ;   throwme(jpl_set_instance_array,no_such_field(Fspec))
  923        )
  924    ;   throwme(jpl_set_instance_array,arg2_is_bad_2(Fspec))
  925    ),
  926    jpl_set_array(Type, Obj, N, Iv, Vs).

 jpl_set_static(+Type, +ClassObj, +FieldName, +Value) is det

We can rely on:

• Type being a class/2 type representing some accessible class
• ClassObj being an instance of java.lang.Class which represents the same class as Type but FieldName could be anything, so we validate it here, look for a suitable (static) field of the target class, then call jpl_set_static_field/4 to attempt to assign Value (which could be anything) to it

NB this does not yet handle shadowed fields correctly.

  941jpl_set_static(Type, ClassObj, Fname, V) :-
  942    (   atom(Fname)                     % the usual case
  943    ->  true
  944    ;   var(Fname)
  945    ->  throwme(jpl_set_static,arg2_is_unbound)
  946    ;   throwme(jpl_set_static,arg2_is_bad(Fname))
  947    ),
  948    findall(  % get all static fields of the denoted class
  949        z4(I,Mods,FID,Tf),
  950        (   jpl_field_spec(Type, I, Fname, Mods, FID, Tf),
  951            member(static, Mods)
  952        ),
  953        Z4s
  954    ),
  955    (   Z4s = []
  956    ->  throwme(jpl_set_static,no_such_public_static_field(field,Fname))
  957    ;   Z4s = [z4(I,Mods,FID,Tf)]       % exactly one synonymous field?
  958    ->  (   member(final, Mods)
  959        ->  throwme(jpl_set_static,cannot_assign_final_field(Fname))
  960        ;   jpl_datum_to_type(V, Tv)
  961        ->  (   jpl_type_fits_type(Tv, Tf)
  962            ->  jpl_set_static_field(Tf, ClassObj, FID, V)
  963            ;   throwme(jpl_set_static,value_not_assignable(Tf,V))
  964            )
  965        ;   throwme(jpl_set_static,arg3_is_bad(field_value,V))
  966        )
  967    ;   throwme(jpl_set_static,multiple_matches(field,Fname))
  968    ).

 jpl_set_array(+ElementType, +Array, +Offset, +DatumQty, +Datums) is det

Datums, of which there are DatumQty, are stashed in successive elements of Array which is an array of ElementType starting at the Offset-th (numbered from 0) throws error(type_error(acyclic,_),context(jpl_datum_to_type/2,_))

  978jpl_set_array(T, A, N, I, Ds) :-
  979    (   jpl_datums_to_types(Ds, Tds)        % most specialised types of given values
  980    ->  (   jpl_types_fit_type(Tds, T)      % all assignable to element type?
  981        ->  true
  982        ;   throwme(jpl_set_array,not_all_values_assignable(T,Ds))
  983        )
  984    ;   throwme(jpl_set_array,not_all_values_convertible(T,Ds))
  985    ),
  986    (   (   T = class(_,_)
  987        ;   T = array(_)                    % array elements are objects
  988        )
  989    ->  (   nth0(J, Ds, D),                 % for each datum
  990            Nd is N+J,                      % compute array index
  991            (   D = {Tq}                    % quoted term?
  992            ->  jni_term_to_jref(Tq, D2)    % convert to a JPL reference to a corresponding org.jpl7.Term object
  993            ;   D = D2
  994            ),
  995            jSetObjectArrayElement(A, Nd, D2),
  996            fail                            % iterate
  997        ;   true
  998        )
  999    ;   jpl_primitive_type(T)               % array elements are primitive values
 1000    ->  jni_type_to_xput_code(T, Xc),
 1001        jni_alloc_buffer(Xc, I, Bp),        % I-element buf of required primitive type
 1002        jpl_set_array_1(Ds, T, 0, Bp),
 1003        jpl_set_elements(T, A, N, I, Bp),
 1004        jni_free_buffer(Bp)
 1005    ;
 1006        % T is neither a class, nor an array type nor a primitive type
 1007        throwme(jpl_set_array,element_type_unknown(array_element_type,T))
 1008    ).

 jpl_set_array_1(+Values, +Type, +BufferIndex, +BufferPointer) is det

successive members of Values are stashed as (primitive) Type from the BufferIndex-th element (numbered from 0) onwards of the buffer indicated by BufferPointer

NB this could be done more efficiently (?) within foreign code...

 1019jpl_set_array_1([], _, _, _).
 1020jpl_set_array_1([V|Vs], Tprim, Ib, Bp) :-
 1021    jni_type_to_xput_code(Tprim, Xc),
 1022    jni_stash_buffer_value(Bp, Ib, V, Xc),
 1023    Ibnext is Ib+1,
 1024    jpl_set_array_1(Vs, Tprim, Ibnext, Bp).
 1025
 1026
 1027jpl_set_elements(boolean, Obj, N, I, Bp) :-
 1028    jSetBooleanArrayRegion(Obj, N, I, jbuf(Bp,boolean)).
 1029jpl_set_elements(char, Obj, N, I, Bp) :-
 1030    jSetCharArrayRegion(Obj, N, I, jbuf(Bp,char)).
 1031jpl_set_elements(byte, Obj, N, I, Bp) :-
 1032    jSetByteArrayRegion(Obj, N, I, jbuf(Bp,byte)).
 1033jpl_set_elements(short, Obj, N, I, Bp) :-
 1034    jSetShortArrayRegion(Obj, N, I, jbuf(Bp,short)).
 1035jpl_set_elements(int, Obj, N, I, Bp) :-
 1036    jSetIntArrayRegion(Obj, N, I, jbuf(Bp,int)).
 1037jpl_set_elements(long, Obj, N, I, Bp) :-
 1038    jSetLongArrayRegion(Obj, N, I, jbuf(Bp,long)).
 1039jpl_set_elements(float, Obj, N, I, Bp) :-
 1040    jSetFloatArrayRegion(Obj, N, I, jbuf(Bp,float)).
 1041jpl_set_elements(double, Obj, N, I, Bp) :-
 1042    jSetDoubleArrayRegion(Obj, N, I, jbuf(Bp,double)).

 jpl_set_instance_field(+Type, +Obj, +FieldID, +V) is det

We can rely on Type, Obj and FieldID being valid, and on V being assignable (if V is a quoted term then it is converted here)

 1050jpl_set_instance_field(boolean, Obj, FieldID, V) :-
 1051    jSetBooleanField(Obj, FieldID, V).
 1052jpl_set_instance_field(byte, Obj, FieldID, V) :-
 1053    jSetByteField(Obj, FieldID, V).
 1054jpl_set_instance_field(char, Obj, FieldID, V) :-
 1055    jSetCharField(Obj, FieldID, V).
 1056jpl_set_instance_field(short, Obj, FieldID, V) :-
 1057    jSetShortField(Obj, FieldID, V).
 1058jpl_set_instance_field(int, Obj, FieldID, V) :-
 1059    jSetIntField(Obj, FieldID, V).
 1060jpl_set_instance_field(long, Obj, FieldID, V) :-
 1061    jSetLongField(Obj, FieldID, V).
 1062jpl_set_instance_field(float, Obj, FieldID, V) :-
 1063    jSetFloatField(Obj, FieldID, V).
 1064jpl_set_instance_field(double, Obj, FieldID, V) :-
 1065    jSetDoubleField(Obj, FieldID, V).
 1066jpl_set_instance_field(class(_,_), Obj, FieldID, V) :-  % also handles byval term assignments
 1067    (   V = {T}                     % quoted term?
 1068    ->  jni_term_to_jref(T, V2)     % convert to a JPL reference to a corresponding org.jpl7.Term object
 1069    ;   V = V2
 1070    ),
 1071    jSetObjectField(Obj, FieldID, V2).
 1072jpl_set_instance_field(array(_), Obj, FieldID, V) :-
 1073    jSetObjectField(Obj, FieldID, V).

 jpl_set_static_field(+Type, +ClassObj, +FieldID, +V)

We can rely on Type, ClassObj and FieldID being valid, and on V being assignable (if V is a quoted term then it is converted here).

 1081jpl_set_static_field(boolean, Obj, FieldID, V) :-
 1082    jSetStaticBooleanField(Obj, FieldID, V).
 1083jpl_set_static_field(byte, Obj, FieldID, V) :-
 1084    jSetStaticByteField(Obj, FieldID, V).
 1085jpl_set_static_field(char, Obj, FieldID, V) :-
 1086    jSetStaticCharField(Obj, FieldID, V).
 1087jpl_set_static_field(short, Obj, FieldID, V) :-
 1088    jSetStaticShortField(Obj, FieldID, V).
 1089jpl_set_static_field(int, Obj, FieldID, V) :-
 1090    jSetStaticIntField(Obj, FieldID, V).
 1091jpl_set_static_field(long, Obj, FieldID, V) :-
 1092    jSetStaticLongField(Obj, FieldID, V).
 1093jpl_set_static_field(float, Obj, FieldID, V) :-
 1094    jSetStaticFloatField(Obj, FieldID, V).
 1095jpl_set_static_field(double, Obj, FieldID, V) :-
 1096    jSetStaticDoubleField(Obj, FieldID, V).
 1097jpl_set_static_field(class(_,_), Obj, FieldID, V) :-    % also handles byval term assignments
 1098    (   V = {T}                         % quoted term?
 1099    ->  jni_term_to_jref(T, V2)         % convert to a JPL reference to a corresponding org.jpl7.Term object
 1100    ;   V = V2
 1101    ),
 1102    jSetStaticObjectField(Obj, FieldID, V2).
 1103jpl_set_static_field(array(_), Obj, FieldID, V) :-
 1104    jSetStaticObjectField(Obj, FieldID, V).

 jpl_get_default_jvm_opts(-Opts:list(atom)) is det

Returns (as a list of atoms) the options which will be passed to the JVM when it is initialised, e.g. ['-Xrs']

 1112jpl_get_default_jvm_opts(Opts) :-
 1113    jni_get_default_jvm_opts(Opts).

 jpl_set_default_jvm_opts(+Opts:list(atom)) is det

Replaces the default JVM initialisation options with those supplied.

 1120jpl_set_default_jvm_opts(Opts) :-
 1121    is_list(Opts),
 1122    length(Opts, N),
 1123    jni_set_default_jvm_opts(N, Opts).

 jpl_get_actual_jvm_opts(-Opts:list(atom)) is semidet

Returns (as a list of atoms) the options with which the JVM was initialised.

Fails silently if a JVM has not yet been started, and can thus be used to test for this.

 1132jpl_get_actual_jvm_opts(Opts) :-
 1133    jni_get_actual_jvm_opts(Opts).
 1134
 1135% ===========================================================================
 1136% Caching
 1137% ===========================================================================
 1138
 1139% In principle the predicates subject to assert/1 must be declared with the
 1140% dynamic/1 directive. However, they are automatically declared as "dynamic"
 1141% if they appear in an assert/1 call first. Anyway, we declare then dynamic
 1142% right here!
 1143
 1144:- dynamic jpl_field_spec_cache/6.      % document this...
 1145:- dynamic jpl_field_spec_is_cached/1.  % document this...
 1146:- dynamic jpl_method_spec_cache/8. 1147:- dynamic jpl_method_spec_is_cached/1. 1148:- dynamic jpl_iref_type_cache/2.

 jpl_classname_type_cache(-Classname:className, -Type:type)

Classname is the atomic name of Type.

NB may denote a class which cannot be found.

 1156:- dynamic jpl_classname_type_cache/2.

 jpl_class_tag_type_cache(-Class:jref, -Type:jpl_type)

Class is a reference to an instance of java.lang.Class which denotes Type.

We index on Class (a jref) so as to keep these objects around even after an atom garbage collection (if needed once, they are likely to be needed again)

(Is it possble to have different Ref for the same ClassType, which happens once several ClassLoaders become involved?) (Most likely)

 1170:- dynamic jpl_class_tag_type_cache/2.

 jpl_assert(+Fact:term)

Assert a fact listed in jpl_assert_policy/2 with "yes" into the Prolog database.

From the SWI-Prolog manual:

"In SWI-Prolog, querying dynamic predicates has the same performance as static ones. The manipulation predicates are fast."

And:

"By default, a predicate declared dynamic (see dynamic/1) is shared by all threads. Each thread may assert, retract and run the dynamic predicate. Synchronisation inside Prolog guarantees the consistency of the predicate. Updates are logical: visible clauses are not affected by assert/retract after a query started on the predicate. In many cases primitives from section 10.4 should be used to ensure that application invariants on the predicate are maintained.

See also

- https://eu.swi-prolog.org/pldoc/man?section=db

- https://eu.swi-prolog.org/pldoc/man?section=threadlocal

 1195jpl_assert(Fact) :-
 1196    (   jpl_assert_policy(Fact, yes)
 1197    ->  assertz(Fact)
 1198    ;   true
 1199    ).
 1200
 1201% ---
 1202% policies
 1203% ---
 1204
 1205jpl_assert_policy(jpl_field_spec_cache(_,_,_,_,_,_), yes).
 1206jpl_assert_policy(jpl_field_spec_is_cached(_), YN) :-
 1207   jpl_assert_policy(jpl_field_spec_cache(_,_,_,_,_,_), YN).
 1208
 1209jpl_assert_policy(jpl_method_spec_cache(_,_,_,_,_,_,_,_), yes).
 1210jpl_assert_policy(jpl_method_spec_is_cached(_), YN) :-
 1211   jpl_assert_policy(jpl_method_spec_cache(_,_,_,_,_,_,_,_), YN).
 1212
 1213jpl_assert_policy(jpl_class_tag_type_cache(_,_), yes).
 1214jpl_assert_policy(jpl_classname_type_cache(_,_), yes).
 1215jpl_assert_policy(jpl_iref_type_cache(_,_), no).   % must correspond to JPL_CACHE_TYPE_OF_REF in jpl.c

 jpl_tidy_iref_type_cache(+Iref) is det

Delete the cached type info, if any, under Iref.

Called from jpl.c's jni_free_iref() via jni_tidy_iref_type_cache()

 1223jpl_tidy_iref_type_cache(Iref) :-
 1224  % write('[decaching types for iref='), write(Iref), write(']'), nl,
 1225    retractall(jpl_iref_type_cache(Iref,_)),
 1226    true.
 1227
 1228jpl_fergus_find_candidate([], Candidate, Candidate, []).
 1229jpl_fergus_find_candidate([X|Xs], Candidate0, Candidate, Rest) :-
 1230    (   jpl_fergus_greater(X, Candidate0)
 1231    ->  Candidate1 = X,
 1232        Rest = [Candidate0|Rest1]
 1233    ;   Candidate1 = Candidate0,
 1234        Rest = [X|Rest1]
 1235    ),
 1236    jpl_fergus_find_candidate(Xs, Candidate1, Candidate, Rest1).
 1237
 1238
 1239jpl_fergus_greater(z5(_,_,_,_,Tps1), z5(_,_,_,_,Tps2)) :-
 1240    jpl_types_fit_types(Tps1, Tps2).
 1241jpl_fergus_greater(z3(_,_,Tps1), z3(_,_,Tps2)) :-
 1242    jpl_types_fit_types(Tps1, Tps2).

 jpl_fergus_is_the_greatest(+Xs:list(T), -GreatestX:T)

Xs is a list of things for which jpl_fergus_greater/2 defines a partial ordering; GreatestX is one of those, than which none is greater; fails if there is more than one such; this algorithm was contributed to c.l.p by Fergus Henderson in response to my "there must be a better way" challenge: there was, this is it

 1253jpl_fergus_is_the_greatest([X|Xs], Greatest) :-
 1254    jpl_fergus_find_candidate(Xs, X, Greatest, Rest),
 1255    forall(
 1256        member(R, Rest),
 1257        jpl_fergus_greater(Greatest, R)
 1258    ).

 jpl_z3s_to_most_specific_z3(+Zs, -Z)

Zs is a list of arity-matching, type-suitable z3(I,MID,Tfps).

Z is the single most specific element of Zs, i.e. that than which no other z3/3 has a more specialised signature (fails if there is more than one such).

 1268jpl_z3s_to_most_specific_z3(Zs, Z) :-
 1269    jpl_fergus_is_the_greatest(Zs, Z).

 jpl_z5s_to_most_specific_z5(+Zs, -Z)

Zs is a list of arity-matching, type-suitable z5(I,Mods,MID,Tr,Tfps)

Z is the single most specific element of Zs, i.e. that than which no other z5/5 has a more specialised signature (fails if there is more than one such)

 1279jpl_z5s_to_most_specific_z5(Zs, Z) :-
 1280    jpl_fergus_is_the_greatest(Zs, Z).

 jpl_pl_lib_version(-Version)

Version is the fully qualified version identifier of the in-use Prolog component (jpl.pl) of JPL.

It should exactly match the version identifiers of JPL's C (jpl.c) and Java (jpl.jar) components.

Example

?- jpl_pl_lib_version(V).
V = '7.6.1'.

 1296jpl_pl_lib_version(VersionString) :-
 1297    jpl_pl_lib_version(Major, Minor, Patch, Status),
 1298    atomic_list_concat([Major,'.',Minor,'.',Patch,'-',Status], VersionString).

 jpl_pl_lib_version(-Major, -Minor, -Patch, -Status)

Major, Minor, Patch and Status are the respective components of the version identifier of the in-use C component (jpl.c) of JPL.

Example

?- jpl:jpl_pl_lib_version(Major, Minor, Patch, Status).
Major = 7,
Minor = 4,
Patch = 0,
Status = alpha.

 1315jpl_pl_lib_version(7, 6, 1, stable).  % jref as blob

 jpl_c_lib_version(-Version)

Version is the fully qualified version identifier of the in-use C component (jpl.c) of JPL.

It should exactly match the version identifiers of JPL's Prolog (jpl.pl) and Java (jpl.jar) components.

Example

?- jpl_c_lib_version(V).
V = '7.4.0-alpha'.

 jpl_java_lib_version(-Version)

Version is the fully qualified version identifier of the in-use Java component (jpl.jar) of JPL.

Example

?- jpl:jpl_java_lib_version(V).
V = '7.4.0-alpha'.

 jpl_java_lib_version(V)

 1344jpl_java_lib_version(V) :-
 1345    jpl_call('org.jpl7.JPL', version_string, [], V).

 jpl_pl_lib_path(-Path:atom)

 1350jpl_pl_lib_path(Path) :-
 1351    module_property(jpl, file(Path)).

 jpl_c_lib_path(-Path:atom)

 1356jpl_c_lib_path(Path) :-
 1357    shlib:current_library(_, _, Path, jpl, _),
 1358    !.

 jpl_java_lib_path(-Path:atom)

 1363jpl_java_lib_path(Path) :-
 1364    jpl_call('org.jpl7.JPL', jarPath, [], Path).

 jCallBooleanMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rbool:boolean)

 1369jCallBooleanMethod(Obj, MethodID, Types, Params, Rbool) :-
 1370    jni_params_put(Params, Types, ParamBuf),
 1371    jni_func(39, Obj, MethodID, ParamBuf, Rbool).

 jCallByteMethod(+Obj:jref, +MethodID:methodId, +Types, +Params:list(datum), -Rbyte:byte)

 1377jCallByteMethod(Obj, MethodID, Types, Params, Rbyte) :-
 1378    jni_params_put(Params, Types, ParamBuf),
 1379    jni_func(42, Obj, MethodID, ParamBuf, Rbyte).

 jCallCharMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rchar:char)

 1385jCallCharMethod(Obj, MethodID, Types, Params, Rchar) :-
 1386    jni_params_put(Params, Types, ParamBuf),
 1387    jni_func(45, Obj, MethodID, ParamBuf, Rchar).

 jCallDoubleMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rdouble:double)

 1392jCallDoubleMethod(Obj, MethodID, Types, Params, Rdouble) :-
 1393    jni_params_put(Params, Types, ParamBuf),
 1394    jni_func(60, Obj, MethodID, ParamBuf, Rdouble).

 jCallFloatMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rfloat:float)

 1399jCallFloatMethod(Obj, MethodID, Types, Params, Rfloat) :-
 1400    jni_params_put(Params, Types, ParamBuf),
 1401    jni_func(57, Obj, MethodID, ParamBuf, Rfloat).

 jCallIntMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rint:int)

 1406jCallIntMethod(Obj, MethodID, Types, Params, Rint) :-
 1407    jni_params_put(Params, Types, ParamBuf),
 1408    jni_func(51, Obj, MethodID, ParamBuf, Rint).

 jCallLongMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rlong:long)

 1413jCallLongMethod(Obj, MethodID, Types, Params, Rlong) :-
 1414    jni_params_put(Params, Types, ParamBuf),
 1415    jni_func(54, Obj, MethodID, ParamBuf, Rlong).

 jCallObjectMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Robj:jref)

 1420jCallObjectMethod(Obj, MethodID, Types, Params, Robj) :-
 1421    jni_params_put(Params, Types, ParamBuf),
 1422    jni_func(36, Obj, MethodID, ParamBuf, Robj).

 jCallShortMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rshort:short)

 1427jCallShortMethod(Obj, MethodID, Types, Params, Rshort) :-
 1428    jni_params_put(Params, Types, ParamBuf),
 1429    jni_func(48, Obj, MethodID, ParamBuf, Rshort).

 jCallStaticBooleanMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rbool:boolean)

 1434jCallStaticBooleanMethod(Class, MethodID, Types, Params, Rbool) :-
 1435    jni_params_put(Params, Types, ParamBuf),
 1436    jni_func(119, Class, MethodID, ParamBuf, Rbool).

 jCallStaticByteMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rbyte:byte)

 1441jCallStaticByteMethod(Class, MethodID, Types, Params, Rbyte) :-
 1442    jni_params_put(Params, Types, ParamBuf),
 1443    jni_func(122, Class, MethodID, ParamBuf, Rbyte).

 jCallStaticCharMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rchar:char)

 1448jCallStaticCharMethod(Class, MethodID, Types, Params, Rchar) :-
 1449    jni_params_put(Params, Types, ParamBuf),
 1450    jni_func(125, Class, MethodID, ParamBuf, Rchar).

 jCallStaticDoubleMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rdouble:double)

 1455jCallStaticDoubleMethod(Class, MethodID, Types, Params, Rdouble) :-
 1456    jni_params_put(Params, Types, ParamBuf),
 1457    jni_func(140, Class, MethodID, ParamBuf, Rdouble).

 jCallStaticFloatMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rfloat:float)

 1462jCallStaticFloatMethod(Class, MethodID, Types, Params, Rfloat) :-
 1463    jni_params_put(Params, Types, ParamBuf),
 1464    jni_func(137, Class, MethodID, ParamBuf, Rfloat).

 jCallStaticIntMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rint:int)

 1469jCallStaticIntMethod(Class, MethodID, Types, Params, Rint) :-
 1470    jni_params_put(Params, Types, ParamBuf),
 1471    jni_func(131, Class, MethodID, ParamBuf, Rint).

 jCallStaticLongMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rlong:long)

 1476jCallStaticLongMethod(Class, MethodID, Types, Params, Rlong) :-
 1477    jni_params_put(Params, Types, ParamBuf),
 1478    jni_func(134, Class, MethodID, ParamBuf, Rlong).

 jCallStaticObjectMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Robj:jref)

 1483jCallStaticObjectMethod(Class, MethodID, Types, Params, Robj) :-
 1484    jni_params_put(Params, Types, ParamBuf),
 1485    jni_func(116, Class, MethodID, ParamBuf, Robj).

 jCallStaticShortMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum), -Rshort:short)

 1490jCallStaticShortMethod(Class, MethodID, Types, Params, Rshort) :-
 1491    jni_params_put(Params, Types, ParamBuf),
 1492    jni_func(128, Class, MethodID, ParamBuf, Rshort).

 jCallStaticVoidMethod(+Class:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum))

 1497jCallStaticVoidMethod(Class, MethodID, Types, Params) :-
 1498    jni_params_put(Params, Types, ParamBuf),
 1499    jni_void(143, Class, MethodID, ParamBuf).

 jCallVoidMethod(+Obj:jref, +MethodID:methodId, +Types:list(type), +Params:list(datum))

 1504jCallVoidMethod(Obj, MethodID, Types, Params) :-
 1505    jni_params_put(Params, Types, ParamBuf),
 1506    jni_void(63, Obj, MethodID, ParamBuf).

 jFindClass(+ClassName:findclassname, -Class:jref)

 1511jFindClass(ClassName, Class) :-
 1512    jni_func(6, ClassName, Class).

 jGetArrayLength(+Array:jref, -Size:int)

 1517jGetArrayLength(Array, Size) :-
 1518    jni_func(171, Array, Size).

 jGetBooleanArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:boolean_buf)

 1523jGetBooleanArrayRegion(Array, Start, Len, Buf) :-
 1524    jni_void(199, Array, Start, Len, Buf).

 jGetBooleanField(+Obj:jref, +FieldID:fieldId, -Rbool:boolean)

 1529jGetBooleanField(Obj, FieldID, Rbool) :-
 1530    jni_func(96, Obj, FieldID, Rbool).

 jGetByteArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:byte_buf)

 1535jGetByteArrayRegion(Array, Start, Len, Buf) :-
 1536    jni_void(200, Array, Start, Len, Buf).

 jGetByteField(+Obj:jref, +FieldID:fieldId, -Rbyte:byte)

 1541jGetByteField(Obj, FieldID, Rbyte) :-
 1542    jni_func(97, Obj, FieldID, Rbyte).

 jGetCharArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:char_buf)

 1547jGetCharArrayRegion(Array, Start, Len, Buf) :-
 1548    jni_void(201, Array, Start, Len, Buf).

 jGetCharField(+Obj:jref, +FieldID:fieldId, -Rchar:char)

 1553jGetCharField(Obj, FieldID, Rchar) :-
 1554    jni_func(98, Obj, FieldID, Rchar).

 jGetDoubleArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:double_buf)

 1559jGetDoubleArrayRegion(Array, Start, Len, Buf) :-
 1560    jni_void(206, Array, Start, Len, Buf).

 jGetDoubleField(+Obj:jref, +FieldID:fieldId, -Rdouble:double)

 1565jGetDoubleField(Obj, FieldID, Rdouble) :-
 1566    jni_func(103, Obj, FieldID, Rdouble).

 jGetFieldID(+Class:jref, +Name:fieldName, +Type:type, -FieldID:fieldId)

 1571jGetFieldID(Class, Name, Type, FieldID) :-
 1572    jpl_type_to_java_field_descriptor(Type, FD),
 1573    jni_func(94, Class, Name, FD, FieldID).

 jGetFloatArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:float_buf)

 1578jGetFloatArrayRegion(Array, Start, Len, Buf) :-
 1579    jni_void(205, Array, Start, Len, Buf).

 jGetFloatField(+Obj:jref, +FieldID:fieldId, -Rfloat:float)

 1584jGetFloatField(Obj, FieldID, Rfloat) :-
 1585    jni_func(102, Obj, FieldID, Rfloat).

 jGetIntArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:int_buf)

 1590jGetIntArrayRegion(Array, Start, Len, Buf) :-
 1591    jni_void(203, Array, Start, Len, Buf).

 jGetIntField(+Obj:jref, +FieldID:fieldId, -Rint:int)

 1596jGetIntField(Obj, FieldID, Rint) :-
 1597    jni_func(100, Obj, FieldID, Rint).

 jGetLongArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:long_buf)

 1602jGetLongArrayRegion(Array, Start, Len, Buf) :-
 1603    jni_void(204, Array, Start, Len, Buf).

 jGetLongField(+Obj:jref, +FieldID:fieldId, -Rlong:long)

 1608jGetLongField(Obj, FieldID, Rlong) :-
 1609    jni_func(101, Obj, FieldID, Rlong).

 jGetMethodID(+Class:jref, +Name:atom, +Type:type, -MethodID:methodId)

 1614jGetMethodID(Class, Name, Type, MethodID) :-
 1615    jpl_type_to_java_method_descriptor(Type, MD),
 1616    jni_func(33, Class, Name, MD, MethodID).

 jGetObjectArrayElement(+Array:jref, +Index:int, -Obj:jref)

 1621jGetObjectArrayElement(Array, Index, Obj) :-
 1622    jni_func(173, Array, Index, Obj).

 jGetObjectClass(+Object:jref, -Class:jref)

 1627jGetObjectClass(Object, Class) :-
 1628    jni_func(31, Object, Class).

 jGetObjectField(+Obj:jref, +FieldID:fieldId, -RObj:jref)

 1633jGetObjectField(Obj, FieldID, Robj) :-
 1634    jni_func(95, Obj, FieldID, Robj).

 jGetShortArrayRegion(+Array:jref, +Start:int, +Len:int, +Buf:short_buf)

 1639jGetShortArrayRegion(Array, Start, Len, Buf) :-
 1640    jni_void(202, Array, Start, Len, Buf).

 jGetShortField(+Obj:jref, +FieldID:fieldId, -Rshort:short)

 1645jGetShortField(Obj, FieldID, Rshort) :-
 1646    jni_func(99, Obj, FieldID, Rshort).

 jGetStaticBooleanField(+Class:jref, +FieldID:fieldId, -Rbool:boolean)

 1651jGetStaticBooleanField(Class, FieldID, Rbool) :-
 1652    jni_func(146, Class, FieldID, Rbool).

 jGetStaticByteField(+Class:jref, +FieldID:fieldId, -Rbyte:byte)

 1657jGetStaticByteField(Class, FieldID, Rbyte) :-
 1658    jni_func(147, Class, FieldID, Rbyte).

 jGetStaticCharField(+Class:jref, +FieldID:fieldId, -Rchar:char)

 1663jGetStaticCharField(Class, FieldID, Rchar) :-
 1664    jni_func(148, Class, FieldID, Rchar).

 jGetStaticDoubleField(+Class:jref, +FieldID:fieldId, -Rdouble:double)

 1669jGetStaticDoubleField(Class, FieldID, Rdouble) :-
 1670    jni_func(153, Class, FieldID, Rdouble).

 jGetStaticFieldID(+Class:jref, +Name:fieldName, +Type:type, -FieldID:fieldId)

 1675jGetStaticFieldID(Class, Name, Type, FieldID) :-
 1676    jpl_type_to_java_field_descriptor(Type, TD),               % cache this?
 1677    jni_func(144, Class, Name, TD, FieldID).

 jGetStaticFloatField(+Class:jref, +FieldID:fieldId, -Rfloat:float)

 1682jGetStaticFloatField(Class, FieldID, Rfloat) :-
 1683    jni_func(152, Class, FieldID, Rfloat).

 jGetStaticIntField(+Class:jref, +FieldID:fieldId, -Rint:int)

 1688jGetStaticIntField(Class, FieldID, Rint) :-
 1689    jni_func(150, Class, FieldID, Rint).

 jGetStaticLongField(+Class:jref, +FieldID:fieldId, -Rlong:long)

 1694jGetStaticLongField(Class, FieldID, Rlong) :-
 1695    jni_func(151, Class, FieldID, Rlong).

 jGetStaticMethodID(+Class:jref, +Name:methodName, +Type:type, -MethodID:methodId)

 1700jGetStaticMethodID(Class, Name, Type, MethodID) :-
 1701    jpl_type_to_java_method_descriptor(Type, TD),
 1702    jni_func(113, Class, Name, TD, MethodID).

 jGetStaticObjectField(+Class:jref, +FieldID:fieldId, -RObj:jref)

 1707jGetStaticObjectField(Class, FieldID, Robj) :-
 1708    jni_func(145, Class, FieldID, Robj).

 jGetStaticShortField(+Class:jref, +FieldID:fieldId, -Rshort:short)

 1713jGetStaticShortField(Class, FieldID, Rshort) :-
 1714    jni_func(149, Class, FieldID, Rshort).

 jGetSuperclass(+Class1:jref, -Class2:jref)

 1719jGetSuperclass(Class1, Class2) :-
 1720    jni_func(10, Class1, Class2).

 jIsAssignableFrom(+Class1:jref, +Class2:jref)

 1725jIsAssignableFrom(Class1, Class2) :-
 1726    jni_func(11, Class1, Class2, @(true)).

 jNewBooleanArray(+Length:int, -Array:jref)

 1731jNewBooleanArray(Length, Array) :-
 1732    jni_func(175, Length, Array).

 jNewByteArray(+Length:int, -Array:jref)

 1737jNewByteArray(Length, Array) :-
 1738    jni_func(176, Length, Array).

 jNewCharArray(+Length:int, -Array:jref)

 1743jNewCharArray(Length, Array) :-
 1744    jni_func(177, Length, Array).

 jNewDoubleArray(+Length:int, -Array:jref)

 1749jNewDoubleArray(Length, Array) :-
 1750    jni_func(182, Length, Array).

 jNewFloatArray(+Length:int, -Array:jref)

 1755jNewFloatArray(Length, Array) :-
 1756    jni_func(181, Length, Array).

 jNewIntArray(+Length:int, -Array:jref)

 1761jNewIntArray(Length, Array) :-
 1762    jni_func(179, Length, Array).

 jNewLongArray(+Length:int, -Array:jref)

 1767jNewLongArray(Length, Array) :-
 1768    jni_func(180, Length, Array).