gnuprologjava问题

Question

我正在使用http://www.gnu.org/software/gnuprologjava/从Java应用程序执行prolog。

在这种情况下，我将使用以下prolog文件：

    /* ghoul is a prolog fact representing the goal state in flat notation */
ghoul(cube('WHITE', 'WHITE', 'WHITE', 'WHITE', 'WHITE', 'WHITE', 'WHITE', 'WHITE','WHITE',    /*White*/
           'GREEN', 'GREEN', 'GREEN', 'GREEN', 'GREEN', 'GREEN', 'GREEN', 'GREEN','GREEN',    /*Green*/
           'RED', 'RED', 'RED', 'RED', 'RED', 'RED', 'RED', 'RED','RED',    /*Red*/
           'BLUE', 'BLUE', 'BLUE', 'BLUE', 'BLUE', 'BLUE', 'BLUE', 'BLUE','BLUE',    /*Blue*/
           'ORANGE', 'ORANGE', 'ORANGE', 'ORANGE', 'ORANGE', 'ORANGE', 'ORANGE', 'ORANGE','ORANGE',    /*Orange, Yellow*/
           'YELLOW', 'YELLOW', 'YELLOW', 'YELLOW', 'YELLOW', 'YELLOW', 'YELLOW', 'YELLOW','YELLOW')).  

/* pieces converts from flat to pieces notation and vice versa*/        
pieces(cube(X01, X02, X03, X04, X05, X06, X07, X08, X09,  /*White*/
            X10, X11, X12, X13, X14, X15, X16, X17, X18,  /*Green*/
            X19, X20, X21, X22, X23, X24, X25, X26, X27,  /*Red*/
            X28, X29, X30, X31, X32, X33, X34, X35, X36,  /*Blue*/
            X37, X38, X39, X40, X41, X42, X43, X44, X45,  /*Orange*/
            X46, X47, X48, X49, X50, X51, X52, X53, X54), /*Yellow*/
       [p(X05), p(X14), p(X23), p(X32), p(X41),p(X50),
        p(X11, X08), p(X15, X22), p(X17, X47), p(X13, X42), /* Green edges */
        p(X38, X04), p(X44, X49),                           /* Orange edges */
        p(X20, X06), p(X26, X51),                           /* Red edges */
        p(X29, X02), p(X33, X40), p(X35, X53), p(X31, X24), /* Blue edges */
        p(X10, X07, X39), p(X12, X19, X09), p(X18, X48, X25), p(X16, X45, X46), /* Green coins */
        p(X28, X03, X21), p(X30, X37, X01), p(X36, X52, X43), p(X34, X27, X54)]).


/* Move of white face */
mov(w, cube(X01, X02, X03, X04, X05, X06, X07, X08, X09,  /*White*/
            X10, X11, X12, X13, X14, X15, X16, X17, X18,  /*Green*/
            X19, X20, X21, X22, X23, X24, X25, X26, X27,  /*Red*/
            X28, X29, X30, X31, X32, X33, X34, X35, X36,  /*Blue*/
            X37, X38, X39, X40, X41, X42, X43, X44, X45,  /*Orange*/
            X46, X47, X48, X49, X50, X51, X52, X53, X54), 
       cube(X03, X06, X09, X02, X05, X08, X01, X04, X07,  /*White*/
            X19, X20, X21, X13, X14, X15, X16, X17, X18,  /*Green*/
            X28, X29, X30, X22, X23, X24, X25, X26, X27,  /*Red*/
            X37, X38, X39, X31, X32, X33, X34, X35, X36,  /*Blue*/
            X10, X11, X12, X40, X41, X42, X43, X44, X45,  /*Orange*/
            X46, X47, X48, X49, X50, X51, X52, X53, X54)).

/* Opposite Moves */        
move(+M, OldState, NewState):- mov(M, OldState, NewState). 
move(-M, OldState, NewState):- mov(M, NewState, OldState).

为什么以下Java代码总是返回-1（在prolog解释器语法中为false），因为解释器能够计算NewState值：

    try {
            URL url = FileLocator.find(Activator.getDefault().getBundle(),
                    new Path("cube.pl"), null);
            url = FileLocator.toFileURL(url);
            Environment env = new Environment();


        // Run the initialization
        env.runInitialization(interpreter);
            env.ensureLoaded(AtomTerm.get(url.getFile()));

   Interpreter interpreter = env.createInterpreter();

            VariableTerm cube = new VariableTerm("cube");
            Term[] args = { cube };
            CompoundTerm goalTerm = new CompoundTerm(AtomTerm.get("ghoul"),
                    args);
            interpreter.runOnce(goalTerm);

            VariableTerm newCube = new VariableTerm("NewCube");
            Term[] args2 = { AtomTerm.get("+w"), cube,
                    newCube };
            CompoundTerm move = new CompoundTerm(AtomTerm.get("move"), args2);
            int runOnce = interpreter.runOnce(move);
            System.out.println(runOnce);
        } catch (Exception e) {
            e.printStackTrace();
        }

Answer 1

在调用runInitialization之前，你不应该调用ensureLoaded吗？ javadoc说：   “在使用它之前和期待答案之前，你必须使用runInitialization（Interpreter）。”

另外，您传递给runInitialization的解释器是否与为运行查询而创建的解释器相同？