Example usage for org.objectweb.asm.tree MethodNode MethodNode

List of usage examples for org.objectweb.asm.tree MethodNode MethodNode

Introduction

In this page you can find the example usage for org.objectweb.asm.tree MethodNode MethodNode.

Prototype

public MethodNode(final int access, final String name, final String descriptor, final String signature,
        final String[] exceptions) 

Source Link

Document

Constructs a new MethodNode .

Usage

From source file:Test1.java

License:Apache License

private static void implementInterface(ClassNode cn) throws Exception {

    // MethodNode fromMethod = new MethodNode(ACC_PUBLIC, "fromData",
    // "(Ljava/io/DataInput;)V", null, new String[] {
    // "java/io/IOException",
    // "java/lang/ClassNotFoundException" });
    // mv = cw.visitMethod(ACC_PUBLIC, "toData", "(Ljava/io/DataOutput;)V",
    // null, new String[] { "java/io/IOException" });
    MethodNode toMethod = new MethodNode(ACC_PUBLIC, "toData", "(Ljava/io/DataOutput;)V", null,
            new String[] { "java/io/IOException" });
    InsnList instToMethod = toMethod.instructions;
    for (int i = 0; i < cn.fields.size(); i++) {
        FieldNode fn = (FieldNode) cn.fields.get(i);
        toMethod(cn.name, fn, instToMethod);
    }/*from ww w  . j av a 2s. c  o m*/
    instToMethod.add(new InsnNode(RETURN));
    cn.methods.add(toMethod);

    ClassWriter cw = new ClassWriter(ClassWriter.COMPUTE_FRAMES);
    cn.accept(cw);
    byte[] bt = cw.toByteArray();

    ClassReader cr = new ClassReader(bt);
    CheckClassAdapter ca = new CheckClassAdapter(cw);
    FileOutputStream fo = new FileOutputStream("d:/x1.log");
    PrintWriter pw = new PrintWriter(fo);
    ca.verify(cr, true, pw);

    ByteArrayClassLoader bacl = new ByteArrayClassLoader(bt);

    Class cls = bacl.loadClass("ynd.test.Ac01");
    DataSerializable di = (DataSerializable) cls.newInstance();
    di.toData(null);
}

From source file:appeng.transformer.asm.ASMTweaker.java

License:Open Source License

@Nullable
@Override/* w w  w .  j a va 2  s . c o  m*/
public byte[] transform(String name, String transformedName, byte[] basicClass) {
    if (basicClass == null) {
        return null;
    }

    try {
        if (transformedName != null && this.privateToPublicMethods.containsKey(transformedName)) {
            ClassNode classNode = new ClassNode();
            ClassReader classReader = new ClassReader(basicClass);
            classReader.accept(classNode, 0);

            for (PublicLine set : this.privateToPublicMethods.get(transformedName)) {
                this.makePublic(classNode, set);
            }

            // CALL VIRTUAL!
            if (transformedName.equals("net.minecraft.client.gui.inventory.GuiContainer")) {
                for (MethodNode mn : classNode.methods) {
                    if (mn.name.equals("func_146977_a") || (mn.name.equals("a") && mn.desc.equals("(Lzk;)V"))) {
                        MethodNode newNode = new MethodNode(Opcodes.ACC_PUBLIC, "func_146977_a_original",
                                mn.desc, mn.signature, EXCEPTIONS);
                        newNode.instructions.add(new VarInsnNode(Opcodes.ALOAD, 0));
                        newNode.instructions.add(new VarInsnNode(Opcodes.ALOAD, 1));
                        newNode.instructions.add(new MethodInsnNode(Opcodes.INVOKESPECIAL, classNode.name,
                                mn.name, mn.desc, false));
                        newNode.instructions.add(new InsnNode(Opcodes.RETURN));
                        this.log(newNode.name + newNode.desc + " - New Method");
                        classNode.methods.add(newNode);
                        break;
                    }
                }

                for (MethodNode mn : classNode.methods) {
                    if (mn.name.equals("func_73863_a") || mn.name.equals("drawScreen")
                            || (mn.name.equals("a") && mn.desc.equals("(IIF)V"))) {
                        Iterator<AbstractInsnNode> i = mn.instructions.iterator();
                        while (i.hasNext()) {
                            AbstractInsnNode in = i.next();
                            if (in.getOpcode() == Opcodes.INVOKESPECIAL) {
                                MethodInsnNode n = (MethodInsnNode) in;
                                if (n.name.equals("func_146977_a")
                                        || (n.name.equals("a") && n.desc.equals("(Lzk;)V"))) {
                                    this.log(n.name + n.desc + " - Invoke Virtual");
                                    mn.instructions.insertBefore(n, new MethodInsnNode(Opcodes.INVOKEVIRTUAL,
                                            n.owner, n.name, n.desc, false));
                                    mn.instructions.remove(in);
                                    break;
                                }
                            }
                        }
                    }
                }
            }

            ClassWriter writer = new ClassWriter(ClassWriter.COMPUTE_MAXS);
            classNode.accept(writer);
            return writer.toByteArray();
        }
    } catch (Throwable ignored) {
    }

    return basicClass;
}

From source file:clientapi.load.transform.impl.ValueAccessorTransformer.java

License:Apache License

/**
 * Creates the field-getter getter method in the specified {@code ClassNode}
 *
 * @param cn The ClassNode/*from  ww w  . ja v  a 2 s  .  com*/
 */
private void createFieldGetter(ClassNode cn) {
    MethodNode mn = new MethodNode(ACC_PUBLIC | ACC_FINAL, "getFieldGetter",
            "(Ljava/lang/String;)Ljava/util/function/Supplier;", null, null);

    // Create a check for all labeled fields in the cache
    fieldCache.forEach((id, fn) -> {
        MethodNode handle;
        {
            // Create lambda handle method
            handle = new MethodNode(ACC_PRIVATE | ACC_SYNTHETIC, "lambda$getFieldGetter$" + current++,
                    "()Ljava/lang/Object;", null, null);

            // Get the field value
            handle.visitVarInsn(ALOAD, 0);
            handle.visitFieldInsn(GETFIELD, cn.name, fn.name, fn.desc);

            // If the field is a primitive type, get the object representation
            String object = getObject(fn.desc);
            if (!object.equals(fn.desc))
                handle.visitMethodInsn(INVOKESTATIC, object, "valueOf", "(" + fn.desc + ")L" + object + ";",
                        false);

            // Return the value
            handle.visitInsn(ARETURN);

            // Add the handle method to the class
            cn.methods.add(handle);
        }

        // Create label for IF statement jump
        Label skip = new Label();

        // Compare the target value with the expected value
        mn.visitVarInsn(ALOAD, 1);
        mn.visitLdcInsn(id);
        mn.visitMethodInsn(INVOKEVIRTUAL, "java/lang/String", "equals", "(Ljava/lang/Object;)Z", false);

        // Jump if the input doesn't match the expected value
        mn.visitJumpInsn(IFEQ, skip);

        // Return the getter
        mn.visitVarInsn(ALOAD, 0);
        mn.visitInvokeDynamicInsn("get", "(L" + cn.name + ";)Ljava/util/function/Supplier;",
                // Define the bootstrap method
                METAFACTORY,
                // Fill the remaining 3 args for the method
                Type.getMethodType("()Ljava/lang/Object;"), createMethodHandle(H_INVOKESPECIAL, cn, handle),
                Type.getMethodType("()Ljava/lang/Object;"));
        mn.visitInsn(ARETURN);

        // Indicate where the IF statement should jump to if it fails
        mn.visitLabel(skip);
    });
    mn.visitInsn(ACONST_NULL);
    mn.visitInsn(ARETURN);

    cn.methods.add(mn);
}

From source file:clientapi.load.transform.impl.ValueAccessorTransformer.java

License:Apache License

/**
 * Creates the field-setter getter method in the specified {@code ClassNode}
 *
 * @see ValueAccessor//from   w w w.  jav a  2s. c om
 *
 * @param cn The ClassNode
 */
private void createFieldSetter(ClassNode cn) {
    MethodNode mn = new MethodNode(ACC_PUBLIC | ACC_FINAL, "getFieldSetter",
            "(Ljava/lang/String;)Ljava/util/function/Consumer;", null, null);

    // Create a check for all labeled fields in the cache
    fieldCache.forEach((id, fn) -> {
        MethodNode handle;
        {
            // Create lambda handle method
            handle = new MethodNode(ACC_PRIVATE | ACC_SYNTHETIC, "lambda$getFieldSetter$" + current++,
                    "(Ljava/lang/Object;)V", null, null);

            handle.visitVarInsn(ALOAD, 0);
            handle.visitVarInsn(ALOAD, 1);
            handle.visitTypeInsn(CHECKCAST, getStrippedDesc(getObject(fn.desc)));

            // If the field is a primitive type, get the primitive value
            String object = getObject(fn.desc);
            if (!object.equals(fn.desc))
                handle.visitMethodInsn(INVOKEVIRTUAL, object, getClassName(fn.desc) + "Value", "()" + fn.desc,
                        false);

            // Set the field value
            handle.visitFieldInsn(PUTFIELD, cn.name, fn.name, fn.desc);
            handle.visitInsn(RETURN);

            // Add the handle method to the class
            cn.methods.add(handle);
        }

        // Create label for IF statement jump
        Label skip = new Label();

        // Compare the target value with the expected value
        mn.visitVarInsn(ALOAD, 1);
        mn.visitLdcInsn(id);
        mn.visitMethodInsn(INVOKEVIRTUAL, "java/lang/String", "equals", "(Ljava/lang/Object;)Z", false);

        // Jump if the input doesn't match the expected value
        mn.visitJumpInsn(IFEQ, skip);

        // Return the setter
        mn.visitVarInsn(ALOAD, 0);
        mn.visitInvokeDynamicInsn("accept", "(L" + cn.name + ";)Ljava/util/function/Consumer;",
                // Define the bootstrap method
                METAFACTORY,
                // Fill the remaining 3 args for the method
                Type.getMethodType("(Ljava/lang/Object;)V"), createMethodHandle(H_INVOKESPECIAL, cn, handle),
                Type.getMethodType("(Ljava/lang/Object;)V"));
        mn.visitInsn(ARETURN);

        // Indicate where the IF statement should jump to if it fails
        mn.visitLabel(skip);
    });
    mn.visitInsn(ACONST_NULL);
    mn.visitInsn(ARETURN);

    cn.methods.add(mn);
}

From source file:co.paralleluniverse.fibers.instrument.InstrumentClass.java

License:Open Source License

@Override
public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature,
        final String[] exceptions) {
    SuspendableType markedSuspendable = null;
    if (suspendableInterface)
        markedSuspendable = SuspendableType.SUSPENDABLE_SUPER;
    if (markedSuspendable == null)
        markedSuspendable = classifier.isSuspendable(db, className, classEntry.getSuperName(),
                classEntry.getInterfaces(), name, desc, signature, exceptions);
    final SuspendableType setSuspendable = classEntry.check(name, desc);

    if (setSuspendable == null)
        classEntry.set(name, desc,/*www.  j a  v a  2 s.c o  m*/
                markedSuspendable != null ? markedSuspendable : SuspendableType.NON_SUSPENDABLE);

    final boolean suspendable = markedSuspendable == SuspendableType.SUSPENDABLE
            | setSuspendable == SuspendableType.SUSPENDABLE;

    if (checkAccess(access) && !isYieldMethod(className, name)) {
        if (isSynchronized(access)) {
            if (!db.isAllowMonitors())
                throw new UnableToInstrumentException("synchronization", className, name, desc);
            else
                db.log(LogLevel.WARNING, "Method %s#%s%s is synchronized", className, name, desc);
        }

        if (methods == null)
            methods = new ArrayList<MethodNode>();
        final MethodNode mn = new MethodNode(access, name, desc, signature, exceptions);

        //            if (suspendable) {
        //                if (db.isDebug())
        //                    db.log(LogLevel.INFO, "Method %s#%s suspendable: %s (markedSuspendable: %s setSuspendable: %s)", className, name, suspendable, markedSuspendable, setSuspendable);
        //
        //                methods.add(mn);
        //                return mn; // this causes the mn to be initialized
        //            } else { // look for @Suspendable or @DontInstrument annotation
        return new MethodVisitor(Opcodes.ASM4, mn) {
            private boolean susp = suspendable;
            private boolean commited = false;

            @Override
            public AnnotationVisitor visitAnnotation(String adesc, boolean visible) {
                if (adesc.equals(ANNOTATION_DESC))
                    susp = true;
                else if (adesc.equals(DONT_INSTRUMENT_ANNOTATION_DESC))
                    susp = false;

                return super.visitAnnotation(adesc, visible);
            }

            @Override
            public void visitCode() {
                commit();
                super.visitCode();
            }

            @Override
            public void visitEnd() {
                if (exception != null)
                    return;

                commit();
                try {
                    super.visitEnd();
                } catch (RuntimeException e) {
                    exception = e;
                }
            }

            private void commit() {
                if (commited)
                    return;
                commited = true;

                if (db.isDebug())
                    db.log(LogLevel.INFO,
                            "Method %s#%s suspendable: %s (markedSuspendable: %s setSuspendable: %s)",
                            className, name, susp, susp, setSuspendable);
                classEntry.set(name, desc,
                        susp ? SuspendableType.SUSPENDABLE : SuspendableType.NON_SUSPENDABLE);

                if (susp)
                    methods.add(mn);
                else {
                    MethodVisitor _mv = makeOutMV(mn);
                    _mv = new JSRInlinerAdapter(_mv, access, name, desc, signature, exceptions);
                    mn.accept(new MethodVisitor(Opcodes.ASM4, _mv) {
                        @Override
                        public void visitEnd() {
                            // don't call visitEnd on MV
                        }
                    }); // write method as-is
                    this.mv = _mv;
                }
            }
        };
        //            }
    }
    return super.visitMethod(access, name, desc, signature, exceptions);
}

From source file:co.paralleluniverse.fibers.instrument.SuspOffsetsAfterInstrClassVisitor.java

License:Open Source License

@Override
public MethodVisitor visitMethod(final int access, final String name, final String desc, final String signature,
        final String[] exceptions) {
    if ((access & Opcodes.ACC_NATIVE) == 0 && !isYieldMethod(className, name)) {
        // Bytecode-level AST of a method, being a MethodVisitor itself can be filled through delegation from another visitor
        final MethodNode mn = new MethodNode(access, name, desc, signature, exceptions);

        // Analyze, fill and enqueue method ASTs
        final MethodVisitor outMV = super.visitMethod(access, name, desc, signature, exceptions);

        return new MethodVisitor(ASMAPI, outMV) {
            private Label currLabel = null;
            private int prevOffset = -1;
            private boolean instrumented;
            private boolean optimized = false;
            private int methodStart = -1, methodEnd = -1;

            private List<Integer> suspOffsetsAfterInstrL = new ArrayList<>();
            private int[] suspCallSites = new int[0];

            @Override//from w w w .  j  ava2  s. co  m
            public AnnotationVisitor visitAnnotation(final String adesc, boolean visible) {
                if (Classes.INSTRUMENTED_DESC.equals(adesc)) {
                    instrumented = true;

                    return new AnnotationVisitor(ASMAPI) { // Only collect info
                        @Override
                        public void visit(String name, Object value) {
                            if (Instrumented.FIELD_NAME_METHOD_START.equals(name))
                                methodStart = (Integer) value;
                            else if (Instrumented.FIELD_NAME_METHOD_END.equals(name))
                                methodEnd = (Integer) value;
                            else if (Instrumented.FIELD_NAME_METHOD_OPTIMIZED.equals(name))
                                optimized = (Boolean) value;
                            else if (Instrumented.FIELD_NAME_SUSPENDABLE_CALL_SITES.equals(name))
                                suspCallSites = (int[]) value;
                            else //noinspection StatementWithEmptyBody
                            if (Instrumented.FIELD_NAME_SUSPENDABLE_CALL_SITES_OFFSETS_AFTER_INSTR.equals(name))
                                ; // Ignore, we're filling it
                            else
                                throw new RuntimeException("Unexpected `@Instrumented` field: " + name);
                        }
                    };
                }

                return super.visitAnnotation(adesc, visible);
            }

            @Override
            public void visitLocalVariable(String name, String desc, String sig, Label lStart, Label lEnd,
                    int slot) {
                super.visitLocalVariable(name, desc, sig, lStart, lEnd, slot);
            }

            @Override
            public void visitLabel(Label label) {
                if (instrumented) {
                    currLabel = label;
                }

                super.visitLabel(label);
            }

            @Override
            public void visitMethodInsn(int opcode, String owner, String name, String desc,
                    boolean isInterface) {
                if (instrumented) {
                    final int type = AbstractInsnNode.METHOD_INSN;
                    if (InstrumentMethod.isSuspendableCall(db, type, opcode, owner, name, desc)
                            && !Classes.STACK_NAME.equals(owner) && // postRestore
                    currLabel != null && currLabel.info instanceof Integer)
                        addLine();
                }

                super.visitMethodInsn(opcode, owner, name, desc, isInterface);
            }

            @Override
            public void visitInvokeDynamicInsn(String name, String desc, Handle handle, Object... objects) {
                if (instrumented) {
                    final int type = AbstractInsnNode.INVOKE_DYNAMIC_INSN;
                    final int opcode = Opcodes.INVOKEDYNAMIC;
                    if (InstrumentMethod.isSuspendableCall(db, type, opcode, handle.getOwner(), name, desc)
                            && !Classes.STACK_NAME.equals(handle.getOwner()) && // postRestore
                    currLabel != null && currLabel.info instanceof Integer)
                        addLine();
                }
                super.visitInvokeDynamicInsn(name, desc, handle, objects);
            }

            @Override
            public void visitEnd() {
                if (instrumented)
                    InstrumentMethod.emitInstrumentedAnn(db, outMV, mn, sourceName, className, optimized,
                            methodStart, methodEnd, suspCallSites, toIntArray(suspOffsetsAfterInstrL));

                super.visitEnd();
            }

            private void addLine() {
                final int currOffset = (Integer) currLabel.info;
                if (currOffset > prevOffset) {
                    suspOffsetsAfterInstrL.add(currOffset);
                    prevOffset = currOffset;
                }
            }
        };
    }

    return super.visitMethod(access, name, desc, signature, exceptions);
}

From source file:com.alibaba.hotswap.processor.constructor.ConstructorVisitor.java

License:Open Source License

@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
    if (name.equals(HotswapConstants.INIT)) {
        MethodNode mn = new MethodNode(access, name, desc, signature, exceptions);
        String mk = HotswapMethodUtil.getMethodKey(name, desc);
        initKeys.add(mk);//from ww  w  .j av  a2s.c o m
        initNodes.put(mk, mn);
        MethodVisitor mv = new FieldHolderInitModifier(mn, access, name, desc, className);
        return mv;
    }

    MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
    mv = new ConstructorInvokeModifier(mv, access, name, desc);
    return mv;
}

From source file:com.alibaba.hotswap.processor.v.VClassGenerateVisitor.java

License:Open Source License

@Override
public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
    if (!isInterface && name.equals(HotswapConstants.CLINIT)) {
        return null;
    }/*from w ww.  ja va2s .  c  o  m*/

    if (name.equals(HotswapConstants.INIT)) {
        MethodNode mn = new MethodNode(access, name, desc, signature, exceptions);

        String mk = HotswapMethodUtil.getMethodKey(name, desc);
        initKeys.add(mk);
        initNodes.put(mk, mn);

        return mn;
    }

    return super.visitMethod(access, name, desc, signature, exceptions);
}

From source file:com.android.build.gradle.internal.incremental.ConstructorBuilder.java

License:Apache License

/**
 * Splits the constructor in two methods, the "set up" and the "body" parts (see above).
 */// www. j  a  va2s.c om
@NonNull
private static Constructor split(@NonNull String owner, @NonNull MethodNode method,
        @NonNull VarInsnNode loadThis, @NonNull MethodInsnNode delegation, int loadThisLine,
        @NonNull List<LocalVariable> variables, int localsAtLoadThis) {
    String[] exceptions = ((List<String>) method.exceptions).toArray(new String[method.exceptions.size()]);

    // Do not add the local array yet, as we treat it as a new variable.
    String newDesc = method.desc.replace(")V", ")Ljava/lang/Object;");
    newDesc = newDesc.replace("(", "([L" + owner + ";");

    Type[] argumentTypes = Type.getArgumentTypes(newDesc);

    // Store the non hotswappable part of the constructor
    List<AbstractInsnNode> fixed = Lists.newLinkedList();
    AbstractInsnNode insn = method.instructions.getFirst();
    while (insn != loadThis) {
        fixed.add(insn);
        insn = insn.getNext();
    }
    fixed.add(loadThis);

    MethodNode initArgs = new MethodNode(Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "init$args", newDesc, null,
            exceptions);
    GeneratorAdapter mv = new GeneratorAdapter(initArgs, initArgs.access, initArgs.name, initArgs.desc);
    int newArgument = mv.newLocal(Type.getType("[Ljava/lang/Object;"));

    mv.loadLocal(newArgument);
    ByteCodeUtils.restoreVariables(mv, variables.subList(0, localsAtLoadThis));

    // Now insert the original method
    insn = loadThis.getNext();
    while (insn != delegation) {
        insn.accept(mv);
        insn = insn.getNext();
    }
    LabelNode labelBefore = new LabelNode();
    labelBefore.accept(mv);

    // Create the args array with the local variables and the values to send to the delegated constructor
    Type[] returnTypes = Type.getArgumentTypes(delegation.desc);
    // The extra elements for the local variables and the qualified name of the constructor.
    mv.push(returnTypes.length + 2);
    mv.newArray(Type.getType(Object.class));
    int args = mv.newLocal(Type.getType("[Ljava/lang/Object;"));
    mv.storeLocal(args);
    for (int i = returnTypes.length - 1; i >= 0; i--) {
        Type type = returnTypes[i];
        mv.loadLocal(args);
        mv.swap(type, Type.getType(Object.class));
        mv.push(i + 2);
        mv.swap(type, Type.INT_TYPE);
        mv.box(type);
        mv.arrayStore(Type.getType(Object.class));
    }

    // Store the qualified name of the constructor in the second element of the array.
    mv.loadLocal(args);
    mv.push(1);
    mv.push(delegation.owner + "." + delegation.desc); // Name of the constructor to be called.
    mv.arrayStore(Type.getType(Object.class));

    // Create the locals array and place it in the first element of the return array
    mv.loadLocal(args);
    mv.push(0);
    mv.push(argumentTypes.length + 1);
    mv.newArray(Type.getType(Object.class));
    ByteCodeUtils.loadVariableArray(mv, ByteCodeUtils.toLocalVariables(Arrays.asList(argumentTypes)), 0);

    mv.dup();
    mv.push(argumentTypes.length);
    ByteCodeUtils.newVariableArray(mv, variables);
    mv.arrayStore(Type.getType(Object.class));

    mv.arrayStore(Type.getType(Object.class));

    mv.loadLocal(args);
    mv.returnValue();

    // Move the first variable up to be an argument
    initArgs.desc = initArgs.desc.replace(")", "[Ljava/lang/Object;)");

    newDesc = method.desc.replace("(", "(L" + owner + ";");
    MethodNode body = new MethodNode(Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "init$body", newDesc, null,
            exceptions);
    mv = new GeneratorAdapter(body, body.access, body.name, body.desc);
    newArgument = mv.newLocal(Type.getType("[Ljava/lang/Object;"));

    LabelNode labelAfter = new LabelNode();
    labelAfter.accept(body);
    Set<LabelNode> bodyLabels = new HashSet<LabelNode>();

    mv.loadLocal(newArgument);
    ByteCodeUtils.restoreVariables(mv, variables);

    insn = delegation.getNext();
    while (insn != null) {
        if (insn instanceof LabelNode) {
            bodyLabels.add((LabelNode) insn);
        }
        insn.accept(mv);
        insn = insn.getNext();
    }

    // manually transfer the exception table from the existing constructor to the new
    // "init$body" method. The labels were transferred just above so we can reuse them.

    //noinspection unchecked
    for (TryCatchBlockNode tryCatch : (List<TryCatchBlockNode>) method.tryCatchBlocks) {
        tryCatch.accept(mv);
    }

    //noinspection unchecked
    for (LocalVariableNode variable : (List<LocalVariableNode>) method.localVariables) {
        boolean startsInBody = bodyLabels.contains(variable.start);
        boolean endsInBody = bodyLabels.contains(variable.end);
        if (!startsInBody && !endsInBody) {
            if (variable.index != 0) { // '#0' on init$args is not 'this'
                variable.accept(initArgs);
            }
        } else if (startsInBody && endsInBody) {
            variable.accept(body);
        } else if (!startsInBody && endsInBody) {
            // The variable spans from the args to the end of the method, create two:
            if (variable.index != 0) { // '#0' on init$args is not 'this'
                LocalVariableNode var0 = new LocalVariableNode(variable.name, variable.desc, variable.signature,
                        variable.start, labelBefore, variable.index);
                var0.accept(initArgs);
            }
            LocalVariableNode var1 = new LocalVariableNode(variable.name, variable.desc, variable.signature,
                    labelAfter, variable.end, variable.index);
            var1.accept(body);
        } else {
            throw new IllegalStateException("Local variable starts after it ends.");
        }
    }
    // Move the first variable up to be an argument
    body.desc = body.desc.replace(")", "[Ljava/lang/Object;)");

    return new Constructor(owner, fixed, loadThis, loadThisLine, initArgs, delegation, body, variables,
            localsAtLoadThis);
}

From source file:com.android.build.gradle.internal.incremental.ConstructorDelegationDetector.java

License:Apache License

/**
 * Splits the constructor in two methods, the "set up" and the "body" parts (see above).
 *///from  www  . java 2  s.  c om
@NonNull
private static Constructor split(@NonNull String owner, @NonNull MethodNode method,
        @NonNull VarInsnNode loadThis, @NonNull MethodInsnNode delegation, int loadThisLine) {
    String[] exceptions = ((List<String>) method.exceptions).toArray(new String[method.exceptions.size()]);
    String newDesc = method.desc.replaceAll("\\((.*)\\)V", "([Ljava/lang/Object;$1)Ljava/lang/Object;");

    MethodNode initArgs = new MethodNode(Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "init$args", newDesc, null,
            exceptions);
    AbstractInsnNode insn = loadThis.getNext();
    while (insn != delegation) {
        insn.accept(initArgs);
        insn = insn.getNext();
    }
    LabelNode labelBefore = new LabelNode();
    labelBefore.accept(initArgs);

    GeneratorAdapter mv = new GeneratorAdapter(initArgs, initArgs.access, initArgs.name, initArgs.desc);
    // Copy the arguments back to the argument array
    // The init_args part cannot access the "this" object and can have side effects on the
    // local variables. Because of this we use the first argument (which we want to keep
    // so all the other arguments remain unchanged) as a reference to the array where to
    // return the values of the modified local variables.
    Type[] types = Type.getArgumentTypes(initArgs.desc);
    int stack = 1; // Skip the first one which is a reference to the local array.
    for (int i = 1; i < types.length; i++) {
        Type type = types[i];
        // This is not this, but the array of local arguments final values.
        mv.visitVarInsn(Opcodes.ALOAD, 0);
        mv.push(i);
        mv.visitVarInsn(type.getOpcode(Opcodes.ILOAD), stack);
        mv.box(type);
        mv.arrayStore(Type.getType(Object.class));
        stack += type.getSize();
    }
    // Create the args array with the values to send to the delegated constructor
    Type[] returnTypes = Type.getArgumentTypes(delegation.desc);
    // The extra element for the qualified name of the constructor.
    mv.push(returnTypes.length + 1);
    mv.newArray(Type.getType(Object.class));
    int args = mv.newLocal(Type.getType("[Ljava/lang/Object;"));
    mv.storeLocal(args);
    for (int i = returnTypes.length - 1; i >= 0; i--) {
        Type type = returnTypes[i];
        mv.loadLocal(args);
        mv.swap(type, Type.getType(Object.class));
        mv.push(i + 1);
        mv.swap(type, Type.INT_TYPE);
        mv.box(type);
        mv.arrayStore(Type.getType(Object.class));
    }

    // Store the qualified name of the constructor in the first element of the array.
    mv.loadLocal(args);
    mv.push(0);
    mv.push(delegation.owner + "." + delegation.desc); // Name of the constructor to be called.
    mv.arrayStore(Type.getType(Object.class));

    mv.loadLocal(args);
    mv.returnValue();

    newDesc = method.desc.replace("(", "(L" + owner + ";");
    MethodNode body = new MethodNode(Opcodes.ACC_PUBLIC | Opcodes.ACC_STATIC, "init$body", newDesc, null,
            exceptions);
    LabelNode labelAfter = new LabelNode();
    labelAfter.accept(body);
    Set<LabelNode> bodyLabels = new HashSet<LabelNode>();

    insn = delegation.getNext();
    while (insn != null) {
        if (insn instanceof LabelNode) {
            bodyLabels.add((LabelNode) insn);
        }
        insn.accept(body);
        insn = insn.getNext();
    }

    // manually transfer the exception table from the existing constructor to the new
    // "init$body" method. The labels were transferred just above so we can reuse them.

    //noinspection unchecked
    for (TryCatchBlockNode tryCatch : (List<TryCatchBlockNode>) method.tryCatchBlocks) {
        tryCatch.accept(body);
    }

    //noinspection unchecked
    for (LocalVariableNode variable : (List<LocalVariableNode>) method.localVariables) {
        boolean startsInBody = bodyLabels.contains(variable.start);
        boolean endsInBody = bodyLabels.contains(variable.end);
        if (!startsInBody && !endsInBody) {
            if (variable.index != 0) { // '#0' on init$args is not 'this'
                variable.accept(initArgs);
            }
        } else if (startsInBody && endsInBody) {
            variable.accept(body);
        } else if (!startsInBody && endsInBody) {
            // The variable spans from the args to the end of the method, create two:
            if (variable.index != 0) { // '#0' on init$args is not 'this'
                LocalVariableNode var0 = new LocalVariableNode(variable.name, variable.desc, variable.signature,
                        variable.start, labelBefore, variable.index);
                var0.accept(initArgs);
            }
            LocalVariableNode var1 = new LocalVariableNode(variable.name, variable.desc, variable.signature,
                    labelAfter, variable.end, variable.index);
            var1.accept(body);
        } else {
            throw new IllegalStateException("Local variable starts after it ends.");
        }
    }

    return new Constructor(loadThis, loadThisLine, initArgs, delegation, body);
}