| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| * |
| */ |
| package org.apache.tomcat.util.bcel.classfile; |
| |
| import java.io.DataInputStream; |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| import java.io.Serializable; |
| import java.util.HashMap; |
| import java.util.Map; |
| |
| import org.apache.tomcat.util.bcel.Constants; |
| |
| /** |
| * Abstract super class for <em>Attribute</em> objects. Currently the |
| * <em>ConstantValue</em>, <em>SourceFile</em>, <em>Code</em>, |
| * <em>Exceptiontable</em>, <em>LineNumberTable</em>, |
| * <em>LocalVariableTable</em>, <em>InnerClasses</em> and |
| * <em>Synthetic</em> attributes are supported. The <em>Unknown</em> |
| * attribute stands for non-standard-attributes. |
| * |
| * @version $Id: Attribute.java,v 1.1 2011/06/28 21:08:23 rherrmann Exp $ |
| * @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A> |
| * @see ConstantValue |
| * @see SourceFile |
| * @see Code |
| * @see Unknown |
| * @see ExceptionTable |
| * @see LineNumberTable |
| * @see LocalVariableTable |
| * @see InnerClasses |
| * @see Synthetic |
| * @see Deprecated |
| * @see Signature |
| */ |
| public abstract class Attribute implements Cloneable, Serializable |
| { |
| private static final long serialVersionUID = 1514136303496688899L; |
| |
| protected int name_index; // Points to attribute name in constant pool |
| |
| protected int length; // Content length of attribute field |
| |
| protected byte tag; // Tag to distiguish subclasses |
| |
| protected ConstantPool constant_pool; |
| |
| protected Attribute(byte tag, int name_index, int length, |
| ConstantPool constant_pool) |
| { |
| this.tag = tag; |
| this.name_index = name_index; |
| this.length = length; |
| this.constant_pool = constant_pool; |
| } |
| |
| /** |
| * Dump attribute to file stream in binary format. |
| * |
| * @param file |
| * Output file stream |
| * @throws IOException |
| */ |
| public void dump(DataOutputStream file) throws IOException |
| { |
| file.writeShort(name_index); |
| file.writeInt(length); |
| } |
| |
| private static final Map<String,AttributeReader> readers = |
| new HashMap<String,AttributeReader>(); |
| |
| /* |
| * Class method reads one attribute from the input data stream. This method |
| * must not be accessible from the outside. It is called by the Field and |
| * Method constructor methods. |
| * |
| * @see Field |
| * @see Method @param file Input stream @param constant_pool Array of |
| * constants @return Attribute @throws IOException @throws |
| * ClassFormatException |
| */ |
| public static final Attribute readAttribute(DataInputStream file, |
| ConstantPool constant_pool) throws IOException, |
| ClassFormatException |
| { |
| ConstantUtf8 c; |
| String name; |
| int name_index; |
| int length; |
| byte tag = Constants.ATTR_UNKNOWN; // Unknown attribute |
| // Get class name from constant pool via `name_index' indirection |
| name_index = file.readUnsignedShort(); |
| c = (ConstantUtf8) constant_pool.getConstant(name_index, |
| Constants.CONSTANT_Utf8); |
| name = c.getBytes(); |
| // Length of data in bytes |
| length = file.readInt(); |
| // Compare strings to find known attribute |
| // System.out.println(name); |
| for (byte i = 0; i < Constants.KNOWN_ATTRIBUTES; i++) |
| { |
| if (name.equals(Constants.ATTRIBUTE_NAMES[i])) |
| { |
| tag = i; // found! |
| break; |
| } |
| } |
| // Call proper constructor, depending on `tag' |
| switch (tag) |
| { |
| case Constants.ATTR_UNKNOWN: |
| AttributeReader r = readers.get(name); |
| if (r != null) |
| { |
| return r.createAttribute(name_index, length, file, |
| constant_pool); |
| } |
| return new Unknown(name_index, length, file, constant_pool); |
| case Constants.ATTR_CONSTANT_VALUE: |
| return new ConstantValue(name_index, length, file, constant_pool); |
| case Constants.ATTR_SOURCE_FILE: |
| return new SourceFile(name_index, length, file, constant_pool); |
| case Constants.ATTR_CODE: |
| return new Code(name_index, length, file, constant_pool); |
| case Constants.ATTR_EXCEPTIONS: |
| return new ExceptionTable(name_index, length, file, constant_pool); |
| case Constants.ATTR_LINE_NUMBER_TABLE: |
| return new LineNumberTable(name_index, length, file, constant_pool); |
| case Constants.ATTR_LOCAL_VARIABLE_TABLE: |
| return new LocalVariableTable(name_index, length, file, |
| constant_pool); |
| case Constants.ATTR_INNER_CLASSES: |
| return new InnerClasses(name_index, length, file, constant_pool); |
| case Constants.ATTR_SYNTHETIC: |
| return new Synthetic(name_index, length, file, constant_pool); |
| case Constants.ATTR_DEPRECATED: |
| return new Deprecated(name_index, length, file, constant_pool); |
| case Constants.ATTR_PMG: |
| return new PMGClass(name_index, length, file, constant_pool); |
| case Constants.ATTR_SIGNATURE: |
| return new Signature(name_index, length, file, constant_pool); |
| case Constants.ATTR_STACK_MAP: |
| return new StackMap(name_index, length, file, constant_pool); |
| case Constants.ATTR_RUNTIME_VISIBLE_ANNOTATIONS: |
| return new RuntimeVisibleAnnotations(name_index, length, file, |
| constant_pool); |
| case Constants.ATTR_RUNTIMEIN_VISIBLE_ANNOTATIONS: |
| return new RuntimeInvisibleAnnotations(name_index, length, file, |
| constant_pool); |
| case Constants.ATTR_RUNTIME_VISIBLE_PARAMETER_ANNOTATIONS: |
| return new RuntimeVisibleParameterAnnotations(name_index, length, |
| file, constant_pool); |
| case Constants.ATTR_RUNTIMEIN_VISIBLE_PARAMETER_ANNOTATIONS: |
| return new RuntimeInvisibleParameterAnnotations(name_index, length, |
| file, constant_pool); |
| case Constants.ATTR_ANNOTATION_DEFAULT: |
| return new AnnotationDefault(name_index, length, file, |
| constant_pool); |
| case Constants.ATTR_LOCAL_VARIABLE_TYPE_TABLE: |
| return new LocalVariableTypeTable(name_index, length, file, |
| constant_pool); |
| case Constants.ATTR_ENCLOSING_METHOD: |
| return new EnclosingMethod(name_index, length, file, constant_pool); |
| case Constants.ATTR_STACK_MAP_TABLE: |
| return new StackMapTable(name_index, length, file, constant_pool); |
| default: // Never reached |
| throw new IllegalStateException("Unrecognized attribute type tag parsed: " + tag); |
| } |
| } |
| |
| /** |
| * @return Name of attribute |
| */ |
| public String getName() |
| { |
| ConstantUtf8 c = (ConstantUtf8) constant_pool.getConstant(name_index, |
| Constants.CONSTANT_Utf8); |
| return c.getBytes(); |
| } |
| |
| |
| /** |
| * @return Tag of attribute, i.e., its type. Value may not be altered, thus |
| * there is no setTag() method. |
| */ |
| public final byte getTag() |
| { |
| return tag; |
| } |
| |
| |
| /** |
| * Use copy() if you want to have a deep copy(), i.e., with all references |
| * copied correctly. |
| * |
| * @return shallow copy of this attribute |
| */ |
| @Override |
| public Object clone() |
| { |
| Object o = null; |
| try |
| { |
| o = super.clone(); |
| } |
| catch (CloneNotSupportedException e) |
| { |
| e.printStackTrace(); // Never occurs |
| } |
| return o; |
| } |
| |
| /** |
| * @return deep copy of this attribute |
| */ |
| public abstract Attribute copy(ConstantPool _constant_pool); |
| |
| /** |
| * @return attribute name. |
| */ |
| @Override |
| public String toString() |
| { |
| return Constants.ATTRIBUTE_NAMES[tag]; |
| } |
| } |
