http://asm.objectweb.org/asm-tree/: A very small and fast Java bytecode manipulation framework (ObjectWeb)
  • Eric Bruneton
  • Eugene Kuleshov
  • Remi Forax 
ASM XML Adapter
Copyright (c) 2004-2011, Eugene Kuleshov
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
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   notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
3. Neither the name of the copyright holders nor the names of its
   contributors may be used to endorse or promote products derived from
   this software without specific prior written permission.
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AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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/***
 * ASM XML Adapter
 * Copyright (c) 2004-2011, Eugene Kuleshov
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.objectweb.asm.xml;

import java.util.HashMap;
import java.util.Map;

import org.objectweb.asm.AnnotationVisitor;
import org.objectweb.asm.Handle;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.util.Printer;
import org.xml.sax.helpers.AttributesImpl;


A MethodVisitor that generates SAX 2.0 events from the visited method. 
Author:Eugene Kuleshov
See Also:
/**
 * A {@link MethodVisitor} that generates SAX 2.0 events from the visited
 * method.
 * 
 * @see org.objectweb.asm.xml.SAXClassAdapter
 * @see org.objectweb.asm.xml.Processor
 * 
 * @author Eugene Kuleshov
 */
public final class SAXCodeAdapter extends MethodVisitor {

    static final String[] TYPES = { "top", "int", "float", "double", "long",
            "null", "uninitializedThis" };

    SAXAdapter sa;

    private final Map<Label, String> labelNames;

    
Constructs a new SAXCodeAdapter object. 
Params:
  • sa – 
           content handler that will be used to send SAX 2.0 events.
/**
     * Constructs a new {@link SAXCodeAdapter SAXCodeAdapter} object.
     * 
     * @param sa
     *            content handler that will be used to send SAX 2.0 events.
     */
    public SAXCodeAdapter(final SAXAdapter sa, final int access) {
        super(Opcodes.ASM4);
        this.sa = sa;
        this.labelNames = new HashMap<Label, String>();

        if ((access & (Opcodes.ACC_ABSTRACT | Opcodes.ACC_INTERFACE | Opcodes.ACC_NATIVE)) == 0) {
            sa.addStart("code", new AttributesImpl());
        }
    }

    @Override
    public final void visitCode() {
    }

    @Override
    public void visitFrame(final int type, final int nLocal,
            final Object[] local, final int nStack, final Object[] stack) {
        AttributesImpl attrs = new AttributesImpl();
        switch (type) {
        case Opcodes.F_NEW:
        case Opcodes.F_FULL:
            if (type == Opcodes.F_NEW) {
                attrs.addAttribute("", "type", "type", "", "NEW");
            } else {
                attrs.addAttribute("", "type", "type", "", "FULL");
            }
            sa.addStart("frame", attrs);
            appendFrameTypes(true, nLocal, local);
            appendFrameTypes(false, nStack, stack);
            break;
        case Opcodes.F_APPEND:
            attrs.addAttribute("", "type", "type", "", "APPEND");
            sa.addStart("frame", attrs);
            appendFrameTypes(true, nLocal, local);
            break;
        case Opcodes.F_CHOP:
            attrs.addAttribute("", "type", "type", "", "CHOP");
            attrs.addAttribute("", "count", "count", "",
                    Integer.toString(nLocal));
            sa.addStart("frame", attrs);
            break;
        case Opcodes.F_SAME:
            attrs.addAttribute("", "type", "type", "", "SAME");
            sa.addStart("frame", attrs);
            break;
        case Opcodes.F_SAME1:
            attrs.addAttribute("", "type", "type", "", "SAME1");
            sa.addStart("frame", attrs);
            appendFrameTypes(false, 1, stack);
            break;
        }
        sa.addEnd("frame");
    }

    private void appendFrameTypes(final boolean local, final int n,
            final Object[] types) {
        for (int i = 0; i < n; ++i) {
            Object type = types[i];
            AttributesImpl attrs = new AttributesImpl();
            if (type instanceof String) {
                attrs.addAttribute("", "type", "type", "", (String) type);
            } else if (type instanceof Integer) {
                attrs.addAttribute("", "type", "type", "",
                        TYPES[((Integer) type).intValue()]);
            } else {
                attrs.addAttribute("", "type", "type", "", "uninitialized");
                attrs.addAttribute("", "label", "label", "",
                        getLabel((Label) type));
            }
            sa.addElement(local ? "local" : "stack", attrs);
        }
    }

    @Override
    public final void visitInsn(final int opcode) {
        sa.addElement(Printer.OPCODES[opcode], new AttributesImpl());
    }

    @Override
    public final void visitIntInsn(final int opcode, final int operand) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "value", "value", "", Integer.toString(operand));
        sa.addElement(Printer.OPCODES[opcode], attrs);
    }

    @Override
    public final void visitVarInsn(final int opcode, final int var) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "var", "var", "", Integer.toString(var));
        sa.addElement(Printer.OPCODES[opcode], attrs);
    }

    @Override
    public final void visitTypeInsn(final int opcode, final String type) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "desc", "desc", "", type);
        sa.addElement(Printer.OPCODES[opcode], attrs);
    }

    @Override
    public final void visitFieldInsn(final int opcode, final String owner,
            final String name, final String desc) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "owner", "owner", "", owner);
        attrs.addAttribute("", "name", "name", "", name);
        attrs.addAttribute("", "desc", "desc", "", desc);
        sa.addElement(Printer.OPCODES[opcode], attrs);
    }

    @Override
    public final void visitMethodInsn(final int opcode, final String owner,
            final String name, final String desc) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "owner", "owner", "", owner);
        attrs.addAttribute("", "name", "name", "", name);
        attrs.addAttribute("", "desc", "desc", "", desc);
        sa.addElement(Printer.OPCODES[opcode], attrs);
    }

    @Override
    public void visitInvokeDynamicInsn(String name, String desc, Handle bsm,
            Object... bsmArgs) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "name", "name", "", name);
        attrs.addAttribute("", "desc", "desc", "", desc);
        attrs.addAttribute("", "bsm", "bsm", "",
                SAXClassAdapter.encode(bsm.toString()));
        sa.addStart("INVOKEDYNAMIC", attrs);
        for (int i = 0; i < bsmArgs.length; i++) {
            sa.addElement("bsmArg", getConstantAttribute(bsmArgs[i]));
        }
        sa.addEnd("INVOKEDYNAMIC");
    }

    @Override
    public final void visitJumpInsn(final int opcode, final Label label) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "label", "label", "", getLabel(label));
        sa.addElement(Printer.OPCODES[opcode], attrs);
    }

    @Override
    public final void visitLabel(final Label label) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "name", "name", "", getLabel(label));
        sa.addElement("Label", attrs);
    }

    @Override
    public final void visitLdcInsn(final Object cst) {
        sa.addElement(Printer.OPCODES[Opcodes.LDC], getConstantAttribute(cst));
    }

    private static AttributesImpl getConstantAttribute(final Object cst) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "cst", "cst", "",
                SAXClassAdapter.encode(cst.toString()));
        attrs.addAttribute("", "desc", "desc", "",
                Type.getDescriptor(cst.getClass()));
        return attrs;
    }

    @Override
    public final void visitIincInsn(final int var, final int increment) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "var", "var", "", Integer.toString(var));
        attrs.addAttribute("", "inc", "inc", "", Integer.toString(increment));
        sa.addElement(Printer.OPCODES[Opcodes.IINC], attrs);
    }

    @Override
    public final void visitTableSwitchInsn(final int min, final int max,
            final Label dflt, final Label... labels) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "min", "min", "", Integer.toString(min));
        attrs.addAttribute("", "max", "max", "", Integer.toString(max));
        attrs.addAttribute("", "dflt", "dflt", "", getLabel(dflt));
        String o = Printer.OPCODES[Opcodes.TABLESWITCH];
        sa.addStart(o, attrs);
        for (int i = 0; i < labels.length; i++) {
            AttributesImpl att2 = new AttributesImpl();
            att2.addAttribute("", "name", "name", "", getLabel(labels[i]));
            sa.addElement("label", att2);
        }
        sa.addEnd(o);
    }

    @Override
    public final void visitLookupSwitchInsn(final Label dflt, final int[] keys,
            final Label[] labels) {
        AttributesImpl att = new AttributesImpl();
        att.addAttribute("", "dflt", "dflt", "", getLabel(dflt));
        String o = Printer.OPCODES[Opcodes.LOOKUPSWITCH];
        sa.addStart(o, att);
        for (int i = 0; i < labels.length; i++) {
            AttributesImpl att2 = new AttributesImpl();
            att2.addAttribute("", "name", "name", "", getLabel(labels[i]));
            att2.addAttribute("", "key", "key", "", Integer.toString(keys[i]));
            sa.addElement("label", att2);
        }
        sa.addEnd(o);
    }

    @Override
    public final void visitMultiANewArrayInsn(final String desc, final int dims) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "desc", "desc", "", desc);
        attrs.addAttribute("", "dims", "dims", "", Integer.toString(dims));
        sa.addElement(Printer.OPCODES[Opcodes.MULTIANEWARRAY], attrs);
    }

    @Override
    public final void visitTryCatchBlock(final Label start, final Label end,
            final Label handler, final String type) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "start", "start", "", getLabel(start));
        attrs.addAttribute("", "end", "end", "", getLabel(end));
        attrs.addAttribute("", "handler", "handler", "", getLabel(handler));
        if (type != null) {
            attrs.addAttribute("", "type", "type", "", type);
        }
        sa.addElement("TryCatch", attrs);
    }

    @Override
    public final void visitMaxs(final int maxStack, final int maxLocals) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "maxStack", "maxStack", "",
                Integer.toString(maxStack));
        attrs.addAttribute("", "maxLocals", "maxLocals", "",
                Integer.toString(maxLocals));
        sa.addElement("Max", attrs);

        sa.addEnd("code");
    }

    @Override
    public void visitLocalVariable(final String name, final String desc,
            final String signature, final Label start, final Label end,
            final int index) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "name", "name", "", name);
        attrs.addAttribute("", "desc", "desc", "", desc);
        if (signature != null) {
            attrs.addAttribute("", "signature", "signature", "",
                    SAXClassAdapter.encode(signature));
        }
        attrs.addAttribute("", "start", "start", "", getLabel(start));
        attrs.addAttribute("", "end", "end", "", getLabel(end));
        attrs.addAttribute("", "var", "var", "", Integer.toString(index));
        sa.addElement("LocalVar", attrs);
    }

    @Override
    public final void visitLineNumber(final int line, final Label start) {
        AttributesImpl attrs = new AttributesImpl();
        attrs.addAttribute("", "line", "line", "", Integer.toString(line));
        attrs.addAttribute("", "start", "start", "", getLabel(start));
        sa.addElement("LineNumber", attrs);
    }

    @Override
    public AnnotationVisitor visitAnnotationDefault() {
        return new SAXAnnotationAdapter(sa, "annotationDefault", 0, null, null);
    }

    @Override
    public AnnotationVisitor visitAnnotation(final String desc,
            final boolean visible) {
        return new SAXAnnotationAdapter(sa, "annotation", visible ? 1 : -1,
                null, desc);
    }

    @Override
    public AnnotationVisitor visitParameterAnnotation(final int parameter,
            final String desc, final boolean visible) {
        return new SAXAnnotationAdapter(sa, "parameterAnnotation", visible ? 1
                : -1, parameter, desc);
    }

    @Override
    public void visitEnd() {
        sa.addEnd("method");
    }

    private final String getLabel(final Label label) {
        String name = labelNames.get(label);
        if (name == null) {
            name = Integer.toString(labelNames.size());
            labelNames.put(label, name);
        }
        return name;
    }

}