File	Doc	Category	Size	Date	Package
Attribute.java	API Doc	Java SE 6 API	10120	Tue Jun 10 00:22:16 BST 2008	com.sun.org.apache.bcel.internal.classfile

Attribute

• java.lang.Object

Fields Summary
protected int	name_index
protected int	length
protected byte	tag
protected ConstantPool	constant_pool
private static HashMap	readers

Constructors Summary
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;

Methods Summary
public abstract void	accept(com.sun.org.apache.bcel.internal.classfile.Visitor v) Called by objects that are traversing the nodes of the tree implicitely defined by the contents of a Java class. I.e., the hierarchy of methods, fields, attributes, etc. spawns a tree of objects. param v Visitor object
public static void	addAttributeReader(java.lang.String name, com.sun.org.apache.bcel.internal.classfile.AttributeReader r) Add an Attribute reader capable of parsing (user-defined) attributes named "name". You should not add readers for the standard attributes such as "LineNumberTable", because those are handled internally. param name the name of the attribute as stored in the class file param r the reader object readers.put(name, r);
public java.lang.Object	clone() Use copy() if you want to have a deep copy(), i.e., with all references copied correctly. return shallow copy of this attribute Object o = null; try { o = super.clone(); } catch(CloneNotSupportedException e) { e.printStackTrace(); // Never occurs } return o;
public abstract com.sun.org.apache.bcel.internal.classfile.Attribute	copy(com.sun.org.apache.bcel.internal.classfile.ConstantPool constant_pool) return deep copy of this attribute
public void	dump(java.io.DataOutputStream file) Dump attribute to file stream in binary format. param file Output file stream throws IOException file.writeShort(name_index); file.writeInt(length);
public final com.sun.org.apache.bcel.internal.classfile.ConstantPool	getConstantPool() return Constant pool used by this object. see ConstantPool return constant_pool;
public final int	getLength() return Length of attribute field in bytes. return length;
public final int	getNameIndex() return Name index in constant pool of attribute name. return name_index;
public final byte	getTag() return Tag of attribute, i.e., its type. Value may not be altered, thus there is no setTag() method. return tag;
public static final com.sun.org.apache.bcel.internal.classfile.Attribute	readAttribute(java.io.DataInputStream file, com.sun.org.apache.bcel.internal.classfile.ConstantPool constant_pool) 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 = (int)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 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 = (AttributeReader)readers.get(name); if(r != null) return r.createAttribute(name_index, length, file, constant_pool); else 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); default: // Never reached throw new IllegalStateException("Ooops! default case reached."); }
public static void	removeAttributeReader(java.lang.String name) Remove attribute reader param name the name of the attribute as stored in the class file readers.remove(name);
public final void	setConstantPool(com.sun.org.apache.bcel.internal.classfile.ConstantPool constant_pool) param constant_pool Constant pool to be used for this object. see ConstantPool this.constant_pool = constant_pool;
public final void	setLength(int length) param Attribute length in bytes. this.length = length;
public final void	setNameIndex(int name_index) param name_index of attribute. this.name_index = name_index;
public java.lang.String	toString() return attribute name. return Constants.ATTRIBUTE_NAMES[tag];