jdk.internal.org.objectweb.asm.Label Java Examples

public ClassVisitorForLabels(ClassWriter cw, Map<Label, Integer> lines,
                             Executable target) {
    super(Opcodes.ASM5, cw);
    this.lineNumbers = lines;

    StringBuilder builder = new StringBuilder("(");
    for (Parameter parameter : target.getParameters()) {
        builder.append(Utils.toJVMTypeSignature(parameter.getType()));
    }
    builder.append(")");
    if (target instanceof Constructor) {
        targetName = "<init>";
        builder.append("V");
    } else {
        targetName = target.getName();
        builder.append(Utils.toJVMTypeSignature(
                ((Method) target).getReturnType()));
    }
    targetDesc = builder.toString();
}
 

@Override
public void visitMaxs(final int maxStack, final int maxLocals) {
    checkStartCode();
    checkEndCode();
    endCode = true;
    for (Label l : usedLabels) {
        if (labels.get(l) == null) {
            throw new IllegalStateException("Undefined label used");
        }
    }
    for (int i = 0; i < handlers.size();) {
        Integer start = labels.get(handlers.get(i++));
        Integer end = labels.get(handlers.get(i++));
        if (start == null || end == null) {
            throw new IllegalStateException(
                    "Undefined try catch block labels");
        }
        if (end.intValue() <= start.intValue()) {
            throw new IllegalStateException(
                    "Emty try catch block handler range");
        }
    }
    checkUnsignedShort(maxStack, "Invalid max stack");
    checkUnsignedShort(maxLocals, "Invalid max locals");
    super.visitMaxs(maxStack, maxLocals);
}
 

/**
 * Checks a stack frame value.
 *
 * @param value
 *            the value to be checked.
 */
void checkFrameValue(final Object value) {
    if (value == Opcodes.TOP || value == Opcodes.INTEGER
            || value == Opcodes.FLOAT || value == Opcodes.LONG
            || value == Opcodes.DOUBLE || value == Opcodes.NULL
            || value == Opcodes.UNINITIALIZED_THIS) {
        return;
    }
    if (value instanceof String) {
        checkInternalName((String) value, "Invalid stack frame value");
        return;
    }
    if (!(value instanceof Label)) {
        throw new IllegalArgumentException("Invalid stack frame value: "
                + value);
    } else {
        usedLabels.add((Label) value);
    }
}
 

/**
 * Returns the field of the Label class whose name is given.
 *
 * @param name
 *            a field name.
 * @return the field of the Label class whose name is given, or null.
 */
private static Field getLabelField(final String name) {
    try {
        Field f = Label.class.getDeclaredField(name);
        f.setAccessible(true);
        return f;
    } catch (NoSuchFieldException e) {
        return null;
    }
}
 

@Override
public void visitTableSwitchInsn(final int min, final int max,
        final Label dflt, final Label... labels) {
    buf.setLength(0);
    buf.append(tab2).append("TABLESWITCH\n");
    for (int i = 0; i < labels.length; ++i) {
        buf.append(tab3).append(min + i).append(": ");
        appendLabel(labels[i]);
        buf.append('\n');
    }
    buf.append(tab3).append("default: ");
    appendLabel(dflt);
    buf.append('\n');
    text.add(buf.toString());
}
 

@Override
public void accept(final MethodVisitor mv) {
    int[] keys = new int[this.keys.size()];
    for (int i = 0; i < keys.length; ++i) {
        keys[i] = this.keys.get(i).intValue();
    }
    Label[] labels = new Label[this.labels.size()];
    for (int i = 0; i < labels.length; ++i) {
        labels[i] = this.labels.get(i).getLabel();
    }
    mv.visitLookupSwitchInsn(dflt.getLabel(), keys, labels);
    acceptAnnotations(mv);
}
 

@Override
public void visitLabel(final Label label) {
    buf.setLength(0);
    declareLabel(label);
    buf.append(name).append(".visitLabel(");
    appendLabel(label);
    buf.append(");\n");
    text.add(buf.toString());
}
 

@Override
public void visitLabel(final Label label) {
    buf.setLength(0);
    declareLabel(label);
    buf.append(name).append(".visitLabel(");
    appendLabel(label);
    buf.append(");\n");
    text.add(buf.toString());
}
 

@Override
public void visitLocalVariable(final String name, final String desc,
        final String signature, final Label start, final Label end,
        final int index) {
    int newIndex = remap(index, Type.getType(desc));
    mv.visitLocalVariable(name, desc, signature, start, end, newIndex);
}
 

@Override
public void accept(final MethodVisitor mv) {
    Label[] labels = new Label[this.labels.size()];
    for (int i = 0; i < labels.length; ++i) {
        labels[i] = this.labels.get(i).getLabel();
    }
    mv.visitTableSwitchInsn(min, max, dflt.getLabel(), labels);
    acceptAnnotations(mv);
}
 

@Override
public void accept(final MethodVisitor mv) {
    int[] keys = new int[this.keys.size()];
    for (int i = 0; i < keys.length; ++i) {
        keys[i] = this.keys.get(i).intValue();
    }
    Label[] labels = new Label[this.labels.size()];
    for (int i = 0; i < labels.length; ++i) {
        labels[i] = this.labels.get(i).getLabel();
    }
    mv.visitLookupSwitchInsn(dflt.getLabel(), keys, labels);
    acceptAnnotations(mv);
}
 

@Override
public void visitLocalVariable(final String name, final String desc,
        final String signature, final Label start, final Label end,
        final int index) {
    p.visitLocalVariable(name, desc, signature, start, end, index);
    super.visitLocalVariable(name, desc, signature, start, end, index);
}
 

@Override
public void visitLineNumber(final int line, final Label start) {
    checkStartCode();
    checkEndCode();
    checkUnsignedShort(line, "Invalid line number");
    checkLabel(start, true, "start label");
    super.visitLineNumber(line, start);
}
 

@Override
public void visitLineNumber(final int line, final Label start) {
    buf.setLength(0);
    buf.append(tab2).append("LINENUMBER ").append(line).append(' ');
    appendLabel(start);
    buf.append('\n');
    text.add(buf.toString());
}
 

/**
 * Appends a declaration of the given label to {@link #buf buf}. This
 * declaration is of the form "Label lXXX = new Label();". Does nothing if
 * the given label has already been declared.
 *
 * @param l
 *            a label.
 */
protected void declareLabel(final Label l) {
    if (labelNames == null) {
        labelNames = new HashMap<Label, String>();
    }
    String name = labelNames.get(l);
    if (name == null) {
        name = "l" + labelNames.size();
        labelNames.put(l, name);
        buf.append("Label ").append(name).append(" = new Label();\n");
    }
}
 

@Override
public void visitJumpInsn(final int opcode, final Label label) {
    if (mv != null) {
        mv.visitJumpInsn(opcode, label);
    }
    execute(opcode, 0, null);
    if (opcode == Opcodes.GOTO) {
        this.locals = null;
        this.stack = null;
    }
}
 

@Override
public AnnotationVisitor visitLocalVariableAnnotation(int typeRef,
        TypePath typePath, Label[] start, Label[] end, int[] index,
        String desc, boolean visible) {
    Printer p = this.p.visitLocalVariableAnnotation(typeRef, typePath,
            start, end, index, desc, visible);
    AnnotationVisitor av = mv == null ? null : mv
            .visitLocalVariableAnnotation(typeRef, typePath, start, end,
                    index, desc, visible);
    return new TraceAnnotationVisitor(av, p);
}
 

@Override
public void visitJumpInsn(final int opcode, final Label label) {
    minSize += 3;
    if (opcode == GOTO || opcode == JSR) {
        maxSize += 5;
    } else {
        maxSize += 8;
    }
    if (mv != null) {
        mv.visitJumpInsn(opcode, label);
    }
}
 

@Override
public void accept(final MethodVisitor methodVisitor) {
    Label[] labelsArray = new Label[this.labels.size()];
    for (int i = 0, n = labelsArray.length; i < n; ++i) {
        labelsArray[i] = this.labels.get(i).getLabel();
    }
    methodVisitor.visitTableSwitchInsn(min, max, dflt.getLabel(), labelsArray);
    acceptAnnotations(methodVisitor);
}
 

/**
 * Makes the given visitor visit this type annotation.
 *
 * @param mv
 *            the visitor that must visit this annotation.
 * @param visible
 *            <tt>true</tt> if the annotation is visible at runtime.
 */
public void accept(final MethodVisitor mv, boolean visible) {
    Label[] start = new Label[this.start.size()];
    Label[] end = new Label[this.end.size()];
    int[] index = new int[this.index.size()];
    for (int i = 0; i < start.length; ++i) {
        start[i] = this.start.get(i).getLabel();
        end[i] = this.end.get(i).getLabel();
        index[i] = this.index.get(i);
    }
    accept(mv.visitLocalVariableAnnotation(typeRef, typePath, start, end,
            index, desc, true));
}
 

@Override
public void visitTableSwitchInsn(final int min, final int max,
        final Label dflt, final Label... labels) {
    mv.visitTableSwitchInsn(min, max, dflt, labels);
    if (constructor) {
        popValue();
        addBranches(dflt, labels);
    }
}
 

/**
 * Appends the name of the given label to {@link #buf buf}. Creates a new
 * label name if the given label does not yet have one.
 *
 * @param l
 *            a label.
 */
protected void appendLabel(final Label l) {
    if (labelNames == null) {
        labelNames = new HashMap<Label, String>();
    }
    String name = labelNames.get(l);
    if (name == null) {
        name = "L" + labelNames.size();
        labelNames.put(l, name);
    }
    buf.append(name);
}
 

@Override
public void visitLookupSwitchInsn(final Label dflt, final int[] keys,
        final Label[] labels) {
    mv.visitLookupSwitchInsn(dflt, keys, labels);
    if (constructor) {
        popValue();
        addBranches(dflt, labels);
    }
}
 

@Override
public void visitLabel(final Label label) {
    mv.visitLabel(label);
    if (constructor && branches != null) {
        List<Object> frame = branches.get(label);
        if (frame != null) {
            stackFrame = frame;
            branches.remove(label);
        }
    }
}
 

@Override
public void visitLookupSwitchInsn(final Label dflt, final int[] keys, final Label[] labels) {
    super.visitLookupSwitchInsn(dflt, keys, labels);
    if (isConstructor && !superClassConstructorCalled) {
        popValue();
        addForwardJumps(dflt, labels);
    }
}
 

public JIMethodInliningAdapter(LocalVariablesSorter mv, Label end, int acc, String desc, Remapper remapper) {
    super(acc, desc, mv, remapper);
    this.lvs = mv;
    this.end = end;
    int offset = isStatic(acc) ? 0 : 1;
    Type[] args = Type.getArgumentTypes(desc);
    for (int i = args.length - 1; i >= 0; i--) {
        super.visitVarInsn(args[i].getOpcode(Opcodes.ISTORE), i + offset);
    }
    if (offset > 0) {
        super.visitVarInsn(Opcodes.ASTORE, 0);
    }
}
 

@Override
public void visitLabel(final Label label) {
    buf.setLength(0);
    declareLabel(label);
    buf.append(name).append(".visitLabel(");
    appendLabel(label);
    buf.append(");\n");
    text.add(buf.toString());
}
 

@Override
public void visitTryCatchBlock(Label start, Label end, Label handler,
        String type) {
    super.visitTryCatchBlock(start, end, handler, type);
    if (constructor && !branches.containsKey(handler)) {
        List<Object> stackFrame = new ArrayList<Object>();
        stackFrame.add(OTHER);
        branches.put(handler, stackFrame);
    }
}
 

@Override
public void accept(final MethodVisitor mv) {
    int[] keys = new int[this.keys.size()];
    for (int i = 0; i < keys.length; ++i) {
        keys[i] = this.keys.get(i).intValue();
    }
    Label[] labels = new Label[this.labels.size()];
    for (int i = 0; i < labels.length; ++i) {
        labels[i] = this.labels.get(i).getLabel();
    }
    mv.visitLookupSwitchInsn(dflt.getLabel(), keys, labels);
}
 

/**
 * Checks that the given label is not null. This method can also check that
 * the label has been visited.
 *
 * @param label
 *            the label to be checked.
 * @param checkVisited
 *            <tt>true</tt> to check that the label has been visited.
 * @param msg
 *            a message to be used in case of error.
 */
void checkLabel(final Label label, final boolean checkVisited,
        final String msg) {
    if (label == null) {
        throw new IllegalArgumentException("Invalid " + msg
                + " (must not be null)");
    }
    if (checkVisited && labels.get(label) == null) {
        throw new IllegalArgumentException("Invalid " + msg
                + " (must be visited first)");
    }
}