Example usage for org.objectweb.asm MethodVisitor visitLabel

List of usage examples for org.objectweb.asm MethodVisitor visitLabel

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Introduction

In this page you can find the example usage for org.objectweb.asm MethodVisitor visitLabel.

Prototype

public void visitLabel(final Label label)

Source Link

Document

Visits a label.

Usage

From source file:org.eclipse.m2m.atl.emftvm.jit.CodeBlockJIT.java

License:Open Source License

/**
 * Generates an execute method for the {@link JITCodeBlock}.
 * @param execute the execute method visitor
 * @param cb the {@link CodeBlock} to JIT-compile
 * @param className the name of the generated class
 *///w  w w  . j  a va  2 s. c  o  m
protected void generateExecute(final MethodVisitor execute, final CodeBlock cb, final String className) {
    execute.visitCode();
    // Generate labels
    final LabelSwitch ls = new LabelSwitch();
    for (Instruction instr : cb.getCode()) {
        ls.doSwitch(instr);
    }
    // Default labels
    final Label start = new Label();
    final Label end = new Label();
    final Label tryStart = new Label();
    final Label vmExceptionHandler = new Label();
    final Label exceptionHandler = new Label();
    final Label catchEnd = new Label();
    // Create exception table
    execute.visitTryCatchBlock(tryStart, vmExceptionHandler, vmExceptionHandler,
            Type.getInternalName(VMException.class));
    execute.visitTryCatchBlock(tryStart, vmExceptionHandler, exceptionHandler,
            Type.getInternalName(Exception.class));
    // Generate bytecode
    execute.visitLabel(start);
    execute.visitVarInsn(ALOAD, 1); // frame
    execute.visitMethodInsn(INVOKEVIRTUAL, Type.getInternalName(StackFrame.class), "getEnv",
            Type.getMethodDescriptor(Type.getType(ExecEnv.class), new Type[0]));
    execute.visitVarInsn(ASTORE, 2);
    execute.visitVarInsn(ALOAD, 2); // env
    execute.visitMethodInsn(INVOKEINTERFACE, Type.getInternalName(ExecEnv.class), "getMonitor",
            Type.getMethodDescriptor(Type.getType(VMMonitor.class), new Type[0]));
    execute.visitVarInsn(ASTORE, 3); // monitor
    execute.visitLabel(tryStart);
    final ByteCodeSwitch bs = new ByteCodeSwitch(this, execute, ls);
    final EList<Instruction> code = cb.getCode();
    final boolean hasMonitor = getEnv().getMonitor() != null;
    for (Instruction instr : code) {
        if (hasMonitor) {
            // do checkMonitor() before each instruction
            generateCheckMonitor(execute, code.indexOf(instr) + 1); // pc
        }
        // generate instruction-specific code
        bs.doSwitch(instr);
    }
    execute.visitJumpInsn(GOTO, catchEnd);
    // catch (VMException e)
    execute.visitLabel(vmExceptionHandler);
    execute.visitVarInsn(ASTORE, 4); // e
    execute.visitVarInsn(ALOAD, 4); // e
    execute.visitInsn(ATHROW); // throw e
    // catch (Exception e)
    execute.visitLabel(exceptionHandler);
    execute.visitVarInsn(ASTORE, 4); // e
    execute.visitTypeInsn(NEW, Type.getInternalName(VMException.class)); // new VMException(): [vme, ...]
    execute.visitInsn(DUP); // [vme, vme, e, ...]
    execute.visitVarInsn(ALOAD, 1); // frame: [frame, vme, vme, ...]
    execute.visitVarInsn(ALOAD, 4); // e: [e, frame, vme, vme, ...]
    execute.visitMethodInsn(INVOKESPECIAL, // new VMException(frame, e): [vme, ...]
            Type.getInternalName(VMException.class), "<init>", Type.getMethodDescriptor(Type.VOID_TYPE,
                    new Type[] { Type.getType(StackFrame.class), Type.getType(Throwable.class) }));
    execute.visitInsn(ATHROW); // throw vme
    // Regular method return
    execute.visitLabel(catchEnd);
    if (cb.getStackLevel() == 0) {
        execute.visitInsn(ACONST_NULL); // push null
    }
    execute.visitInsn(ARETURN); // return result
    execute.visitLabel(end);
    // Create local variable table
    execute.visitLocalVariable("this", "L" + className + ";", null, start, end, 0);
    execute.visitLocalVariable("frame", Type.getDescriptor(StackFrame.class), null, start, end, 1);
    execute.visitLocalVariable("env", Type.getDescriptor(ExecEnv.class), null, start, end, 2);
    execute.visitLocalVariable("monitor", Type.getDescriptor(VMMonitor.class), null, start, end, 3);
    execute.visitLocalVariable("e", Type.getDescriptor(VMException.class), null, vmExceptionHandler,
            exceptionHandler, 4);
    execute.visitLocalVariable("e", Type.getDescriptor(Exception.class), null, exceptionHandler, catchEnd, 4);
    // Finalise
    execute.visitMaxs(0, 0); // recalculate 
    execute.visitEnd();
}

From source file:org.eclipse.m2m.atl.emftvm.jit.CodeBlockJIT.java

License:Open Source License

/**
 * Generates bytecode for checking the VM monitor
 * @param mv the method visitor to generate code for
 * @param pc the current program counter
 *///from   w ww  .j  av a  2s .  c  om
protected static void generateCheckMonitor(final MethodVisitor mv, final int pc) {
    // Labels
    final Label notTerminated = new Label();
    // Generate bytecode
    mv.visitVarInsn(ALOAD, 3); // monitor: [..., monitor]
    mv.visitMethodInsn(INVOKEINTERFACE, // monitor.isTerminated(): [..., boolean]
            Type.getInternalName(VMMonitor.class), "isTerminated",
            Type.getMethodDescriptor(Type.BOOLEAN_TYPE, new Type[0]));
    mv.visitJumpInsn(IFEQ, notTerminated); // jump if isTerminated == false: [...]
    mv.visitTypeInsn(NEW, Type.getInternalName(VMException.class)); // new VMException: [..., vme]
    mv.visitInsn(DUP); // [..., vme, vme]
    mv.visitVarInsn(ALOAD, 1); // frame: [..., vme, vme, frame]
    mv.visitLdcInsn("Execution terminated."); // [..., vme, vme, frame, msg]
    mv.visitMethodInsn(INVOKESPECIAL, // vme.<init>(frame, msg): [..., vme]
            Type.getInternalName(VMException.class), "<init>", Type.getMethodDescriptor(Type.VOID_TYPE,
                    new Type[] { Type.getType(StackFrame.class), Type.getType(String.class) }));
    mv.visitInsn(ATHROW); // throw vme: [...]
    mv.visitLabel(notTerminated);
    mv.visitVarInsn(ALOAD, 1); // frame: [..., frame]
    generatePushInt(mv, pc); // [..., frame, pc]
    mv.visitMethodInsn(INVOKEVIRTUAL, // frame.setPc(pc): [...] 
            Type.getInternalName(StackFrame.class), "setPc",
            Type.getMethodDescriptor(Type.VOID_TYPE, new Type[] { Type.INT_TYPE }));
    mv.visitVarInsn(ALOAD, 3); // monitor: [..., monitor]
    mv.visitVarInsn(ALOAD, 1); // frame: [..., monitor, frame]
    mv.visitMethodInsn(INVOKEINTERFACE, // monitor.step(frame): [...]
            Type.getInternalName(VMMonitor.class), "step",
            Type.getMethodDescriptor(Type.VOID_TYPE, new Type[] { Type.getType(StackFrame.class) }));
}

From source file:org.eclipse.objectteams.otredyn.bytecode.asm.AddGlobalTeamActivationAdapter.java

License:Open Source License

@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
    synchronized (AddGlobalTeamActivationAdapter.class) {
        if (!done && isMainMethod(name, desc, access)) {
            done = true;//from  w  ww .j  a v  a  2  s  .  c om
            final MethodVisitor methodVisitor = cv.visitMethod(access, name, desc, null, null);
            return new AdviceAdapter(this.api, methodVisitor, access, name, desc) {
                @Override
                protected void onMethodEnter() {
                    List<String> teams = getTeamsFromConfigFile();
                    for (String aTeam : teams) {
                        Label start, end, typeHandler, ctorHandler, after;

                        String aTeamSlash = aTeam.replace('.', '/');

                        // new SomeTeam():
                        methodVisitor.visitLabel(start = new Label());
                        methodVisitor.visitTypeInsn(Opcodes.NEW, aTeamSlash);
                        //       .activate(Team.ALL_THREADS):
                        methodVisitor.visitInsn(Opcodes.DUP);
                        methodVisitor.visitMethodInsn(Opcodes.INVOKESPECIAL, aTeamSlash, "<init>", "()V",
                                false);
                        methodVisitor.visitFieldInsn(Opcodes.GETSTATIC, ClassNames.TEAM_SLASH, "ALL_THREADS",
                                "Ljava/lang/Thread;");
                        methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, aTeamSlash, "activate",
                                "(Ljava/lang/Thread;)V", false);

                        methodVisitor.visitLabel(end = new Label());
                        methodVisitor.visitJumpInsn(Opcodes.GOTO, after = new Label());

                        // catch (ClassNotFoundException, NoClassDefFoundError):
                        //   System.err.println(...)
                        methodVisitor.visitLabel(typeHandler = new Label());
                        methodVisitor.visitInsn(Opcodes.POP); // discard the exception
                        methodVisitor.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/System", "err",
                                "Ljava/io/PrintStream;");
                        methodVisitor.visitLdcInsn("Config error: Team class '" + aTeam + "' in config file '"
                                + TEAM_CONFIG_FILE + "' can not be found!");
                        methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/io/PrintStream", "println",
                                "(Ljava/lang/String;)V", false);
                        methodVisitor.visitJumpInsn(Opcodes.GOTO, after);
                        methodVisitor.visitTryCatchBlock(start, end, typeHandler,
                                "java/lang/ClassNotFoundException");
                        // dup to avoid stackmap errors (ASM bug at 1.8)
                        methodVisitor.visitLabel(typeHandler = new Label());
                        methodVisitor.visitInsn(Opcodes.POP); // discard the exception
                        methodVisitor.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/System", "err",
                                "Ljava/io/PrintStream;");
                        methodVisitor.visitLdcInsn("Config error: Team class '" + aTeam + "' in config file '"
                                + TEAM_CONFIG_FILE + "' can not be found!");
                        methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/io/PrintStream", "println",
                                "(Ljava/lang/String;)V", false);
                        methodVisitor.visitJumpInsn(Opcodes.GOTO, after);
                        //
                        methodVisitor.visitTryCatchBlock(start, end, typeHandler,
                                "java/lang/NoClassDefFoundError");

                        // catch (NoSuchMethodError):
                        //   System.err.println(...)
                        methodVisitor.visitLabel(ctorHandler = new Label());
                        methodVisitor.visitInsn(Opcodes.POP); // discard the exception
                        methodVisitor.visitFieldInsn(Opcodes.GETSTATIC, "java/lang/System", "err",
                                "Ljava/io/PrintStream;");
                        methodVisitor.visitLdcInsn(
                                "Activation failed: Team class '" + aTeam + "' has no default constuctor!");
                        methodVisitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/io/PrintStream", "println",
                                "(Ljava/lang/String;)V", false);
                        methodVisitor.visitTryCatchBlock(start, end, ctorHandler,
                                "java/lang/NoSuchMethodError");

                        methodVisitor.visitLabel(after);
                    }
                }

                @Override
                public void visitMaxs(int maxStack, int maxLocals) {
                    super.visitMaxs(Math.max(maxStack, 3), maxLocals);
                }
            };
        }
        return null;
    }
}

From source file:org.eclipse.objectteams.otredyn.bytecode.asm.AddThreadNotificationAdapter.java

License:Open Source License

@Override
public MethodVisitor visitMethod(int access, String methodName, String desc, String signature,
        String[] exceptions) {/*from  w ww  . j a v  a2s  .  co  m*/
    if (INIT.equals(methodName)) {
        // into each constructor ...
        final MethodVisitor methodVisitor = cv.visitMethod(access, methodName, desc, null, null);
        return new AdviceAdapter(this.api, methodVisitor, access, methodName, desc) {
            @Override
            public void invokeConstructor(Type type, Method method) {
                super.invokeConstructor(type, method);
                // ... that contains a super(..) call (rather than this(..)):
                if (type.getInternalName().equals(clazz.getInternalSuperClassName())) {
                    // insert:
                    // this._OT$creationThread = Thread.currentThread();
                    methodVisitor.visitIntInsn(Opcodes.ALOAD, 0);
                    methodVisitor.visitMethodInsn(Opcodes.INVOKESTATIC, ClassNames.THREAD_SLASH, CURRENT_THREAD,
                            CURRENT_THREAD_DESC, false);
                    methodVisitor.visitFieldInsn(Opcodes.PUTFIELD, clazz.getInternalName(), CREATION_THREAD,
                            THREAD_DESC);
                }
            }
        };
    } else if (RUN.equals(methodName) && RUN_DESC.equals(desc)) {
        final MethodVisitor methodVisitor = cv.visitMethod(access, methodName, desc, null, null);
        return new AdviceAdapter(this.api, methodVisitor, access, methodName, desc) {

            Label start = new Label(); // start of method (scope of new local)
            Label end = new Label(); // end of method
            int isThreadStartIdx; // new local: boolean _OT$isThreadStart

            @Override
            protected void onMethodEnter() {
                methodVisitor.visitLabel(start);
                isThreadStartIdx = newLocal(Type.BOOLEAN_TYPE);
                methodVisitor.visitLocalVariable("_OT$isThreadStart", "Z", null, start, end, isThreadStartIdx);
                // TeamThreadManager.newThreadStarted(false, this._OT$creationThread)
                methodVisitor.visitInsn(Opcodes.ICONST_0);
                methodVisitor.visitIntInsn(Opcodes.ALOAD, 0);
                methodVisitor.visitFieldInsn(Opcodes.GETFIELD, clazz.getInternalName(), CREATION_THREAD,
                        THREAD_DESC);
                methodVisitor.visitMethodInsn(Opcodes.INVOKESTATIC, ClassNames.TEAM_THREAD_MANAGER_SLASH,
                        NEW_THREAD_STARTED, NEW_THREAD_STARTED_DESC, false);
                methodVisitor.visitIntInsn(Opcodes.ISTORE, isThreadStartIdx);
                // this._OT$creationThread = null; // avoid leak
                methodVisitor.visitIntInsn(Opcodes.ALOAD, 0);
                methodVisitor.visitInsn(Opcodes.ACONST_NULL);
                methodVisitor.visitFieldInsn(Opcodes.PUTFIELD, clazz.getInternalName(), CREATION_THREAD,
                        THREAD_DESC);
            }

            @Override
            protected void onMethodExit(int opcode) {
                insertThreadEndedNotification();
            }

            @Override
            public void endMethod() {
                methodVisitor.visitLabel(end);

                // insert another threadEnded notification as a handler for Throwable
                Label handler = new Label();
                methodVisitor.visitLabel(handler);
                insertThreadEndedNotification();
                methodVisitor.visitInsn(Opcodes.ATHROW); // rethrow caught exception

                methodVisitor.visitTryCatchBlock(start, end, handler, ClassNames.THROWABLE_SLASH);
                methodVisitor.visitMaxs(0, 0);
            }

            void insertThreadEndedNotification() {
                Label skip = new Label();
                // insert:
                // if (_OT$isThreadStart) TeamThreadManager.threadEnded();
                methodVisitor.visitIntInsn(Opcodes.ILOAD, isThreadStartIdx);
                methodVisitor.visitJumpInsn(Opcodes.IFEQ, skip);
                methodVisitor.visitMethodInsn(Opcodes.INVOKESTATIC, ClassNames.TEAM_THREAD_MANAGER_SLASH,
                        THREAD_ENDED, THREAD_ENDED_DESC, false);
                methodVisitor.visitLabel(skip);
            }
        };
    }
    return null;
}

From source file:org.eclipse.sisu.peaberry.internal.ImportGlue.java

License:Open Source License

@SuppressWarnings("PMD.ExcessiveMethodLength")
private static void wrap(final ClassWriter cw, final String proxyName, final Method method) {

    final String methodName = method.getName();

    final String descriptor = getMethodDescriptor(method);
    final String[] exceptions = getInternalNames(method.getExceptionTypes());

    // simple delegating proxy, so don't need synchronization on wrapper method
    final int modifiers = method.getModifiers() & ~(ABSTRACT | NATIVE | SYNCHRONIZED);

    final MethodVisitor v = cw.visitMethod(modifiers, methodName, descriptor, null, exceptions);

    final Label start = new Label();
    final Label invoke = new Label();
    final Label end = new Label();

    final Label ungetR = new Label();
    final Label finalR = new Label();
    final Label catchX = new Label();
    final Label ungetX = new Label();
    final Label finalX = new Label();

    v.visitCode();//from   w  w w  . java 2  s  .  c o m

    // support try{ get(); } finally { unget(); } model
    v.visitTryCatchBlock(start, ungetR, catchX, null);
    v.visitTryCatchBlock(ungetR, finalR, finalR, EXCEPTION_NAME);
    v.visitTryCatchBlock(ungetX, finalX, finalX, EXCEPTION_NAME);

    // store handle as "this"
    v.visitVarInsn(ALOAD, 0);
    v.visitFieldInsn(GETFIELD, proxyName, PROXY_HANDLE, IMPORT_DESC);
    v.visitInsn(DUP);
    v.visitVarInsn(ASTORE, 0);

    v.visitLabel(start);

    // dereference handle to get actual service instance
    v.visitMethodInsn(INVOKEINTERFACE, IMPORT_NAME, "get", "()" + OBJECT_DESC);
    v.visitInsn(DUP);

    // null => ServiceUnavailableException
    v.visitJumpInsn(IFNONNULL, invoke);
    v.visitTypeInsn(NEW, UNAVAILABLE_NAME);
    v.visitInsn(DUP);
    v.visitMethodInsn(INVOKESPECIAL, UNAVAILABLE_NAME, "<init>", "()V");
    v.visitInsn(ATHROW);

    v.visitLabel(invoke);

    final Class<?> clazz = method.getDeclaringClass();
    final String subjectName = getInternalName(clazz);

    if (!clazz.isInterface()) {
        v.visitTypeInsn(CHECKCAST, subjectName);
    }

    int i = 1;
    for (final Type t : getArgumentTypes(method)) {
        v.visitVarInsn(t.getOpcode(ILOAD), i);
        i = i + t.getSize();
    }

    // delegate to real method
    if (clazz.isInterface()) {
        v.visitMethodInsn(INVOKEINTERFACE, subjectName, methodName, descriptor);
    } else {
        v.visitMethodInsn(INVOKEVIRTUAL, subjectName, methodName, descriptor);
    }

    final Type returnType = getReturnType(method);

    if (VOID != returnType.getSort()) {
        v.visitVarInsn(returnType.getOpcode(ISTORE), 1);
    }

    v.visitLabel(ungetR);

    // unget on return
    v.visitVarInsn(ALOAD, 0);
    v.visitMethodInsn(INVOKEINTERFACE, IMPORT_NAME, "unget", VOID_DESC);
    v.visitInsn(ACONST_NULL);

    v.visitLabel(finalR);

    if (VOID != returnType.getSort()) {
        v.visitVarInsn(returnType.getOpcode(ILOAD), 1);
    }

    v.visitInsn(returnType.getOpcode(IRETURN));

    // cache initial exception
    v.visitLabel(catchX);
    v.visitVarInsn(ASTORE, 1);

    v.visitLabel(ungetX);

    // unget on exception
    v.visitVarInsn(ALOAD, 0);
    v.visitMethodInsn(INVOKEINTERFACE, IMPORT_NAME, "unget", VOID_DESC);
    v.visitInsn(ACONST_NULL);

    v.visitLabel(finalX);

    // restore initial exception
    v.visitVarInsn(ALOAD, 1);
    v.visitInsn(ATHROW);

    v.visitLabel(end);
    v.visitMaxs(0, 0);
    v.visitEnd();
}

From source file:org.enerj.enhancer.ClassEnhancer.java

License:Open Source License

/**
 * Generate the getfield/putfield replacement methods (enerj_Get_* and enerj_Set_*)
 * for persistent fields.//from w  w  w  .  j a  v  a  2s.c  o m
 * Parameters to the generated methods conveniently match the stack frame of
 * getfield and putfield.
 *
 * @param aField a Field for which the methods will be generated.
 */
private void emitPersistentFieldMediationMethods(Field aField) {
    int fieldScope = aField.getAccessModifiers() & (ACC_PRIVATE | ACC_PUBLIC | ACC_PROTECTED);
    String fieldName = aField.getName();
    String methodNameSuffix = getFieldMethodNameSuffix(mClassName, fieldName);
    String fieldType = aField.getDescriptor();
    int opcodeOffset = getOpcodeOffsetForDescriptor(fieldType);
    // TODO do we need to worry about fields with parameterized types? 
    //String genericSignature = Type.getDescriptor( aField.getGenericType() );

    MethodVisitor mv = cv.visitMethod(fieldScope | ACC_STATIC, FIELD_ACCESSOR_PREFIX + methodNameSuffix,
            '(' + mThisClassDescr + ')' + fieldType, null, null);
    Label label0 = new Label();
    mv.visitLabel(label0);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, "enerj_mLoaded", "Z");
    Label label1 = new Label();
    mv.visitJumpInsn(IFNE, label1);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, "enerj_mNew", "Z");
    mv.visitJumpInsn(IFNE, label1);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitInsn(ICONST_0);
    mv.visitMethodInsn(INVOKESTATIC, sPersistableHelperClassSlashed, "checkLoaded",
            "(Lorg/enerj/core/Persistable;Z)V");
    mv.visitLabel(label1);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, fieldName, fieldType);
    mv.visitInsn(getReturnOpcodeForDescriptor(fieldType));
    Label label3 = new Label();
    mv.visitLabel(label3);
    mv.visitLocalVariable("anInstance", mThisClassDescr, null, label0, label3, 0);
    mv.visitMaxs(0, 0);

    ///--------------
    // Mutator (Setter). Because of the == comparison, the method is a little different
    // for primitives, Strings (final class that implements equals() properly), and regular objects.

    mv = cv.visitMethod(fieldScope | ACC_STATIC, FIELD_MUTATOR_PREFIX + methodNameSuffix,
            '(' + mThisClassDescr + fieldType + ")V", null, null);
    mv.visitCode();

    // Check if checkLoaded needs to be called. Call if (!enerj_mLoaded && !enerj_mNew)
    Label mutatorStartLabel = new Label();
    mv.visitLabel(mutatorStartLabel);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, "enerj_mLoaded", "Z");
    Label mutatorLabel1 = new Label();
    mv.visitJumpInsn(IFNE, mutatorLabel1);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, "enerj_mNew", "Z");
    mv.visitJumpInsn(IFNE, mutatorLabel1);

    // Call checkLoaded
    mv.visitVarInsn(ALOAD, 0);
    mv.visitInsn(ICONST_1);
    mv.visitMethodInsn(INVOKESTATIC, sPersistableHelperClassSlashed, "checkLoaded",
            "(Lorg/enerj/core/Persistable;Z)V");
    mv.visitLabel(mutatorLabel1);

    // Check if the field's value is actually changing. For primitives, we use ==;
    // for special classes declared final (e.g., String, Integer), we use equals(); 
    // and for other objects we use == (identity).

    Label notModifiedLabel = new Label();

    if (MetaData.isPrimitive(fieldType)) {
        // Push parameter 1 - the new value
        mv.visitVarInsn(ILOAD + opcodeOffset, 1);
        // This
        mv.visitVarInsn(ALOAD, 0);
        // Current value
        mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, fieldName, fieldType);

        char type = fieldType.charAt(0);
        switch (type) {
        case 'B':
        case 'Z':
        case 'C':
        case 'S':
        case 'I':
            mv.visitJumpInsn(IF_ICMPEQ, notModifiedLabel);
            break;

        case 'F':
            mv.visitInsn(FCMPL);
            mv.visitJumpInsn(IFEQ, notModifiedLabel);
            break;

        case 'J':
            mv.visitInsn(LCMP);
            mv.visitJumpInsn(IFEQ, notModifiedLabel);
            break;

        case 'D':
            mv.visitInsn(DCMPL);
            mv.visitJumpInsn(IFEQ, notModifiedLabel);
            break;

        default:
            throw new RuntimeException("Unknown primitive type: " + type);
        }
    } else if (fieldType.equals("Ljava/lang/String;") || fieldType.equals("Ljava/lang/Integer;")
            || fieldType.equals("Ljava/lang/Long;") || fieldType.equals("Ljava/lang/Byte;")
            || fieldType.equals("Ljava/lang/Boolean;") || fieldType.equals("Ljava/lang/Character;")
            || fieldType.equals("Ljava/lang/Short;") || fieldType.equals("Ljava/lang/Float;")
            || fieldType.equals("Ljava/lang/Double;")) {

        // One of the core final immutable types. Use equals() to compare values, like this:
        // "if ((aValue == null{1} && anInstance.mString != null{2}) || (aValue != null{3} && !aValue.equals(anInstance.mString){4})" ...

        // {1}: aValue == null
        mv.visitVarInsn(ALOAD, 1);
        Label imEqualsLabel = new Label();
        mv.visitJumpInsn(IFNONNULL, imEqualsLabel);

        // {2}: anInstance.mString != null
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, fieldName, fieldType);
        Label imStoreLabel = new Label();
        mv.visitJumpInsn(IFNONNULL, imStoreLabel);

        // {3}: aValue != null
        mv.visitLabel(imEqualsLabel);
        mv.visitVarInsn(ALOAD, 1);
        mv.visitJumpInsn(IFNULL, notModifiedLabel);

        // {4}: equals()...
        // Push parameter 1 - the new value
        mv.visitVarInsn(ALOAD, 1);
        // Current Value
        mv.visitVarInsn(ALOAD, 0);
        mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, fieldName, fieldType);
        // Compare !equals()
        mv.visitMethodInsn(INVOKEVIRTUAL, aField.getInternalName(), "equals", "(Ljava/lang/Object;)Z");
        mv.visitJumpInsn(IFNE, notModifiedLabel);

        mv.visitLabel(imStoreLabel);
    } else {
        // Some other Object -- use identity ==
        // Push parameter 1 - the new value
        mv.visitVarInsn(ALOAD, 1);
        // This
        mv.visitVarInsn(ALOAD, 0);
        // Current value
        mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, fieldName, fieldType);
        mv.visitJumpInsn(IF_ACMPEQ, notModifiedLabel);
    }

    // Store the value
    // Mark owner object as modified - short circuit if already marked modified
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, "enerj_mModified", "Z");
    Label mutatorLabel2 = new Label();
    mv.visitJumpInsn(IFNE, mutatorLabel2);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitMethodInsn(INVOKESTATIC, sPersistableHelperClassSlashed, "addModified", sPersistableVoidSignature);
    mv.visitLabel(mutatorLabel2);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitVarInsn(ILOAD + opcodeOffset, 1);
    mv.visitFieldInsn(PUTFIELD, mThisClassNameSlashed, fieldName, fieldType);
    mv.visitLabel(notModifiedLabel);
    mv.visitInsn(RETURN);

    Label mutatorEndlabel = new Label();
    mv.visitLabel(mutatorEndlabel);
    mv.visitLocalVariable("anInstance", mThisClassDescr, null, mutatorStartLabel, mutatorEndlabel, 0);
    mv.visitLocalVariable("aValue", fieldType, null, mutatorStartLabel, mutatorEndlabel, 1);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:org.enerj.enhancer.ClassEnhancer.java

License:Open Source License

/**
 * Generate the getfield/putfield replacement methods (enerj_Get_* and enerj_Set_*)
 * for non-static transient fields./* w  w w  .ja v  a2 s  .c om*/
 * Parameters to the generated methods conveniently match the stack frame of
 * getfield and putfield.
 *
 * @param aField a Field for which the methods will be generated.
 */
private void emitTransientFieldMediationMethods(Field aField) {
    int fieldScope = aField.getAccessModifiers() & (ACC_PRIVATE | ACC_PUBLIC | ACC_PROTECTED);
    String fieldName = aField.getName();
    String methodNameSuffix = getFieldMethodNameSuffix(mClassName, fieldName);
    String fieldType = aField.getDescriptor();

    // Accessor (Getter).
    MethodVisitor mv = cv.visitMethod(fieldScope | ACC_STATIC, FIELD_ACCESSOR_PREFIX + methodNameSuffix,
            '(' + mThisClassDescr + ')' + fieldType, null, null);
    mv.visitCode();
    Label startLabel = new Label();
    mv.visitLabel(startLabel);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitFieldInsn(GETFIELD, mThisClassNameSlashed, fieldName, fieldType);
    mv.visitInsn(getReturnOpcodeForDescriptor(fieldType));
    Label endLabel = new Label();
    mv.visitLabel(endLabel);
    mv.visitLocalVariable("anInstance", mThisClassDescr, null, startLabel, endLabel, 0);
    mv.visitMaxs(0, 0);
    mv.visitEnd();

    // Mutator (Setter).
    mv = cv.visitMethod(fieldScope | ACC_STATIC, FIELD_MUTATOR_PREFIX + methodNameSuffix,
            '(' + mThisClassDescr + fieldType + ")V", null, null);
    mv.visitCode();
    startLabel = new Label();
    mv.visitLabel(startLabel);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitVarInsn(getLoadOpcodeForDescriptor(fieldType), 1);
    mv.visitFieldInsn(PUTFIELD, mThisClassNameSlashed, fieldName, fieldType);
    mv.visitInsn(RETURN);
    endLabel = new Label();
    mv.visitLabel(endLabel);
    mv.visitLocalVariable("anInstance", mThisClassDescr, null, startLabel, endLabel, 0);
    mv.visitLocalVariable("aValue", fieldType, null, startLabel, endLabel, 1);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:org.enerj.enhancer.ClassEnhancer.java

License:Open Source License

/**
 * Generate the getstatic/putstatic replacement methods (enerj_Get_* and enerj_Set_*)
 * for static transient fields. //from   w  w w  .  j  a v  a  2  s .c  o  m
 * Parameters to the generated methods conveniently match the stack frame of
 * getstatic and putstatic.
 *
 * @param aField a Field for which the methods will be generated.
 */
private void emitStaticFieldMediationMethods(Field aField) {
    int fieldScope = aField.getAccessModifiers() & (ACC_PRIVATE | ACC_PUBLIC | ACC_PROTECTED);
    String fieldName = aField.getName();
    String methodNameSuffix = getFieldMethodNameSuffix(mClassName, fieldName);
    String fieldType = aField.getDescriptor();

    // Accessor (Getter).
    MethodVisitor mv = cv.visitMethod(fieldScope | ACC_STATIC, FIELD_ACCESSOR_PREFIX + methodNameSuffix,
            "()" + fieldType, null, null);
    mv.visitCode();
    mv.visitFieldInsn(GETSTATIC, mThisClassNameSlashed, fieldName, fieldType);
    mv.visitInsn(getReturnOpcodeForDescriptor(fieldType));
    mv.visitMaxs(0, 0);
    mv.visitEnd();

    // Mutator (Setter).
    mv = cv.visitMethod(fieldScope | ACC_STATIC, FIELD_MUTATOR_PREFIX + methodNameSuffix,
            '(' + fieldType + ")V", null, null);
    mv.visitCode();
    Label startLabel = new Label();
    mv.visitLabel(startLabel);
    mv.visitVarInsn(getLoadOpcodeForDescriptor(fieldType), 0);
    mv.visitFieldInsn(PUTSTATIC, mThisClassNameSlashed, fieldName, fieldType);
    mv.visitInsn(RETURN);
    Label endLabel = new Label();
    mv.visitLabel(endLabel);
    mv.visitLocalVariable("aValue", fieldType, null, startLabel, endLabel, 0);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}

From source file:org.enerj.enhancer.ClassEnhancer.java

License:Open Source License

/**
 * Emit the special clone() method on a top-level persistable. This is
 * generated when a top-level Persistable doesn't have a clone method.
 * It ensures initPersistableClone is called if a sub-class implements clone().
 *//*from   w  ww .  ja v  a  2 s.  c om*/
private void emitClone() {
    // TODO Only add this exception if superclass throws it. Object does, while java.util.Date does not.
    // TODO Either that or never throw it and wrap the super.clone() in a try/catch.
    // TODO catch part should never happen. If it does, return null.
    String[] exceptions = new String[] { "java/lang/CloneNotSupportedException" };
    MethodVisitor mv = cv.visitMethod(ACC_PUBLIC, "clone", "()Ljava/lang/Object;", null, exceptions);

    mv.visitCode();
    Label startLabel = new Label();
    mv.visitLabel(startLabel);
    mv.visitVarInsn(ALOAD, 0);
    mv.visitMethodInsn(INVOKESPECIAL, mSuperClassNameSlashed, "clone", "()Ljava/lang/Object;");
    mv.visitInsn(DUP);
    mv.visitTypeInsn(CHECKCAST, sPersistableClassSlashed);
    mv.visitMethodInsn(INVOKESTATIC, sPersistableHelperClassSlashed, "initPersistableClone",
            sPersistableVoidSignature);
    mv.visitInsn(ARETURN);
    Label endLabel = new Label();
    mv.visitLabel(endLabel);

    mv.visitLocalVariable("this", mThisClassDescr, null, startLabel, endLabel, 0);
    mv.visitMaxs(0, 0);
    mv.visitEnd();
}