asmcontenthandler.java.old

jboss规则引擎

   * Map of the active {@link Label Label} instances for current method.
   */
  protected Map labels;

  /**
   * Constructs a new {@link ASMContentHandler ASMContentHandler} object.
   * 
   * @param os output stream to write generated class. 
   * @param computeMax <tt>true</tt> if the maximum stack size and the maximum
   *      number of local variables must be automatically computed. 
   *      This value is passed to {@link ClassWriter ClassWriter}
   *      instance.
   */
  public ASMContentHandler (OutputStream os, boolean computeMax) {
    this.os = os;
    this.computeMax = computeMax;
  }

  /**
   * Process notification of the start of an XML element being reached.
   * 
   * @param ns - The Namespace URI, or the empty string if the element has no
   *                Namespace URI or if Namespace processing is not being performed.
   * @param localName - The local name (without prefix), or the empty string if Namespace
   *                processing is not being performed.
   * @param qName - The qualified name (with prefix), or the empty string if
   *                qualified names are not available.
   * @param list - The attributes attached to the element. If there are no
   *                attributes, it shall be an empty Attributes object.
   * @exception SAXException if a parsing error is to be reported
   */
  public final void startElement (String ns, String localName, String qName,
      Attributes list) throws SAXException {
    // the actual element name is either in localName or qName, depending
    // on whether the parser is namespace aware
    String name = localName;
    if (name == null || name.length() < 1) {
      name = qName;
    }

    start(MAP[hashcode(name)], list);
  }

  /**
   * Process notification of the end of an XML element being reached.
   *
   * @param ns - The Namespace URI, or the empty string if the
   *   element has no Namespace URI or if Namespace processing is not
   *   being performed.
   * @param localName - The local name (without prefix), or the empty
   *   string if Namespace processing is not being performed.
   * @param qName - The qualified XML 1.0 name (with prefix), or the
   *   empty string if qualified names are not available.
   * 
   * @exception SAXException if a parsing error is to be reported
   */
  public final void endElement (String ns, String localName, String qName)
      throws SAXException {
    // the actual element name is either in localName or qName, depending
    // on whether the parser is namespace aware
    String name = localName;
    if (name == null || name.length() < 1) {
      name = qName;
    }
    
    end(MAP[hashcode(name)]);
  }

  /**
   * Process notification of the end of a document and write generated bytecode 
   * into output stream.
   *
   * @exception SAXException if parsing or writing error is to be reported.
   */
  public final void endDocument () throws SAXException {
    try {
      os.write(cw.toByteArray());
    } catch (IOException ex) {
      throw new SAXException(ex.toString(), ex);
    }
  }

  private void start (int element, Attributes attrs) {
    Map vals;
    int access;
    String owner, name, desc, signature, value;
    boolean visible;
    Label start, end;
    
    int opcode = element & 0xFF;
    
    switch (element >> 8) {
      case CLASS:
        int major = Integer.parseInt(attrs.getValue("major"));
        int minor = Integer.parseInt(attrs.getValue("minor"));
        cw = new ClassWriter(computeMax);
        vals = new HashMap();
        vals.put("version", new Integer(minor << 16 | major));
        vals.put("access", attrs.getValue("access"));
        vals.put("name", attrs.getValue("name"));
        vals.put("parent", attrs.getValue("parent"));
        vals.put("source", attrs.getValue("source"));
        vals.put("signature", attrs.getValue("signature"));
        vals.put("interfaces", new ArrayList());
        push(vals);
        break;
        
      case INTERFACE:
        ((List)((Map)peek()).get("interfaces")).add(attrs.getValue("name"));
        break;
        
      case SOURCE:
        String file = attrs.getValue("file");
        String debug = attrs.getValue("debug");
        cw.visitSource(file, debug);
        break;

      case INNERCLASS:
        access = getAccess(attrs.getValue("access"));
        name = attrs.getValue("name");
        String outerName = attrs.getValue("outerName");
        String innerName = attrs.getValue("innerName");
        cw.visitInnerClass(name, outerName, innerName, access);
        break;

      case OUTERCLASS:
        owner = attrs.getValue("owner");
        name = attrs.getValue("name");
        desc = attrs.getValue("desc");
        cw.visitOuterClass(owner, name, desc);
        break;
        
      case ANNOTATION:
        desc = attrs.getValue("desc");
        visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();
        Object v = peek();
        if (v instanceof ClassVisitor) {
          push(((ClassVisitor)v).visitAnnotation(desc, visible));
        } else if (v instanceof FieldVisitor) {
          push(((FieldVisitor)v).visitAnnotation(desc, visible));
        } else if (v instanceof MethodVisitor) {
          push(((MethodVisitor)v).visitAnnotation(desc, visible));
        }
        break;
        
      case ANNOTATION_DEFAULT:
        push(((MethodVisitor)peek()).visitAnnotationDefault());
        break;
        
      case PARAMETER_ANNOTATION:
        int parameter = Integer.parseInt(attrs.getValue("parameter"));
        desc = attrs.getValue("desc");
        visible = Boolean.valueOf(attrs.getValue("visible")).booleanValue();
        push(((MethodVisitor)peek()).visitParameterAnnotation(parameter, desc, visible));
        break;

      case ANNOTATION_VALUE:
        name = attrs.getValue("name");
        desc = attrs.getValue("desc");
        value = attrs.getValue("value");
        ((AnnotationVisitor)peek()).visit(name, getValue(desc, value));
        break;
        
      case ANNOTATION_VALUE_ENUM:
        name = attrs.getValue("name");
        desc = attrs.getValue("desc");
        value = attrs.getValue("value");
        ((AnnotationVisitor)peek()).visitEnum(name, desc, value);
        break;
        
      case ANNOTATION_VALUE_ANNOTATION:
        name = attrs.getValue("name");
        desc = attrs.getValue("desc");
        push(((AnnotationVisitor)peek()).visitAnnotation(name, desc));
        break;
        
      case ANNOTATION_VALUE_ARRAY:
        name = attrs.getValue("name");
        push(((AnnotationVisitor)peek()).visitArray(name));
        break;
        
      case FIELD:
        access = getAccess(attrs.getValue("access"));
        name = attrs.getValue("name");
        signature = attrs.getValue("signature");
        desc = attrs.getValue("desc");
        Object val = getValue(desc, attrs.getValue("value"));
        push(cw.visitField(access, name, desc, signature, val));
        break;
        
      case METHOD:
        labels = new HashMap();
        vals = new HashMap();
        vals.put("access", attrs.getValue("access"));
        vals.put("name", attrs.getValue("name"));
        vals.put("desc", attrs.getValue("desc"));
        vals.put("signature", attrs.getValue("signature"));
        vals.put("exceptions", new ArrayList());
        push(vals);
        break;
        
      case EXCEPTION:
        ((List)((Map)peek()).get("exceptions")).add(attrs.getValue("name"));
        break;

      case TRYCATCH:
        start = getLabel(attrs.getValue("start"));
        end = getLabel(attrs.getValue("end"));
        Label handler = getLabel(attrs.getValue("handler"));
        String type = attrs.getValue("type");
        getMethodVisitor().visitTryCatchBlock(start, end, handler, type);
        break;
        
      case MAX:
        int maxStack = Integer.parseInt(attrs.getValue("maxStack"));
        int maxLocals = Integer.parseInt(attrs.getValue("maxLocals"));
        getMethodVisitor().visitMaxs(maxStack, maxLocals);
        break;

      case LOCALVAR:
        name = attrs.getValue("name");
        desc = attrs.getValue("desc");
        signature = attrs.getValue("signature");
        start = getLabel(attrs.getValue("start"));
        end = getLabel(attrs.getValue("end"));
        int var = Integer.parseInt(attrs.getValue("var"));
        getMethodVisitor().visitLocalVariable(name, desc, signature, start, end, var);
        break;

      case LINENUMBER:
        int line = Integer.parseInt(attrs.getValue("line"));
        start = getLabel(attrs.getValue("start"));
        getMethodVisitor().visitLineNumber(line, start);
        break;
        
      case INSN:
        getMethodVisitor().visitInsn(opcode);
        break;

      case INT_INSN:
        getMethodVisitor().visitIntInsn(opcode, Integer.parseInt(attrs.getValue("value")));
        break;

      case VAR_INSN:
        getMethodVisitor().visitVarInsn(opcode, Integer.parseInt(attrs.getValue("var")));
        break;
        
      case TYPE_INSN:
        getMethodVisitor().visitTypeInsn(opcode, attrs.getValue("desc"));
        break;
        
      case FIELD_INSN:
        getMethodVisitor().visitFieldInsn(opcode, attrs.getValue("owner"), attrs.getValue("name"), attrs.getValue("desc"));
        break;
        
      case METHOD_INSN:
        getMethodVisitor().visitMethodInsn(opcode, attrs.getValue("owner"), attrs.getValue("name"), attrs.getValue("desc"));
        break;
        
      case JUMP_INSN:
        getMethodVisitor().visitJumpInsn(opcode, getLabel(attrs.getValue("label")));
        break;
        
      case LABEL:
        getMethodVisitor().visitLabel(getLabel(attrs.getValue("name")));
        break;

      case TABLELABEL:
        vals = (Map)peek();
        ((List)vals.get("labels")).add(getLabel(attrs.getValue("name")));
        if (attrs.getValue("key") != null) {
          ((List)vals.get("keys")).add(attrs.getValue("key"));
        }
        break;
        
      case LDC_INSN:
        getMethodVisitor().visitLdcInsn(getValue(attrs.getValue("desc"), attrs.getValue("cst")));
        break;