org.apache.tomcat.util.bcel.classfile.Unknown Maven / Gradle / Ivy
/*
* 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.util.HashMap;
import java.util.Map;
import org.apache.tomcat.util.bcel.Constants;
/**
* This class represents a reference to an unknown (i.e.,
* application-specific) attribute of a class. It is instantiated from the
* Attribute.readAttribute() method. Applications that need to
* read in application-specific attributes should create an AttributeReader implementation and
* attach it via Attribute.addAttributeReader.
*
* @version $Id: Unknown.java 1057670 2011-01-11 14:52:05Z markt $
* @see org.apache.tomcat.util.bcel.classfile.Attribute
* @see org.apache.tomcat.util.bcel.classfile.AttributeReader
* @author M. Dahm
*/
public final class Unknown extends Attribute {
private static final long serialVersionUID = -4152422704743201314L;
private byte[] bytes;
private String name;
private static final Map unknown_attributes =
new HashMap();
/**
* Create a non-standard attribute.
*
* @param name_index Index in constant pool
* @param length Content length in bytes
* @param bytes Attribute contents
* @param constant_pool Array of constants
*/
public Unknown(int name_index, int length, byte[] bytes, ConstantPool constant_pool) {
super(Constants.ATTR_UNKNOWN, name_index, length, constant_pool);
this.bytes = bytes;
name = ((ConstantUtf8) constant_pool.getConstant(name_index, Constants.CONSTANT_Utf8))
.getBytes();
unknown_attributes.put(name, this);
}
/**
* Construct object from file stream.
* @param name_index Index in constant pool
* @param length Content length in bytes
* @param file Input stream
* @param constant_pool Array of constants
* @throws IOException
*/
Unknown(int name_index, int length, DataInputStream file, ConstantPool constant_pool)
throws IOException {
this(name_index, length, (byte[]) null, constant_pool);
if (length > 0) {
bytes = new byte[length];
file.readFully(bytes);
}
}
/**
* Dump unknown bytes to file stream.
*
* @param file Output file stream
* @throws IOException
*/
@Override
public final void dump( DataOutputStream file ) throws IOException {
super.dump(file);
if (length > 0) {
file.write(bytes, 0, length);
}
}
/**
* @return name of attribute.
*/
@Override
public final String getName() {
return name;
}
/**
* @return String representation.
*/
@Override
public final String toString() {
if (length == 0 || bytes == null) {
return "(Unknown attribute " + name + ")";
}
String hex;
if (length > 10) {
byte[] tmp = new byte[10];
System.arraycopy(bytes, 0, tmp, 0, 10);
hex = Utility.toHexString(tmp) + "... (truncated)";
} else {
hex = Utility.toHexString(bytes);
}
return "(Unknown attribute " + name + ": " + hex + ")";
}
/**
* @return deep copy of this attribute
*/
@Override
public Attribute copy( ConstantPool _constant_pool ) {
Unknown c = (Unknown) clone();
if (bytes != null) {
c.bytes = new byte[bytes.length];
System.arraycopy(bytes, 0, c.bytes, 0, bytes.length);
}
c.constant_pool = _constant_pool;
return c;
}
}