CodeAttr.java

package com.pan.jvm.attr;

import com.pan.jvm.clz.ClassFile;
import com.pan.jvm.cmd.ByteCodeCommand;
import com.pan.jvm.loader.ByteCodeIterator;


public class CodeAttr extends AttributeInfo {
	private int maxStack ;
	private int maxLocals ;
	private int codeLen ;
	private String code;
	public String getCode() {
		return code;
	}

	private ByteCodeCommand[] cmds ;
	public ByteCodeCommand[] getCmds() {
		return cmds;
	}
	private LineNumberTable lineNumTable;
	private LocalVariableTable localVarTable;
	private StackMapTable stackMapTable;
	
	public CodeAttr(int attrNameIndex, int attrLen, int maxStack, int maxLocals, int codeLen,String code /*ByteCodeCommand[] cmds*/) {
		super(attrNameIndex, attrLen);
		this.maxStack = maxStack;
		this.maxLocals = maxLocals;
		this.codeLen = codeLen;
		this.code = code;
		//this.cmds = cmds;
	}

	public void setLineNumberTable(LineNumberTable t) {
		this.lineNumTable = t;
	}

	public void setLocalVariableTable(LocalVariableTable t) {
		this.localVarTable = t;		
	}
	
	public static CodeAttr parse(ClassFile clzFile, ByteCodeIterator iter){
		int attrNameIndex = iter.nextU2ToInt();
		int attrLen = iter.nextU4ToInt();
		int maxStack = iter.nextU2ToInt();
		int maxLocals = iter.nextU2ToInt();
		int codeLen = iter.nextU4ToInt();

		String code = iter.nextUxToHexString(codeLen);

		System.out.println("CODE-code: "+code);

		CodeAttr codeAttr = new CodeAttr(attrNameIndex, attrLen, maxStack, maxLocals, codeLen, code);

		int exceptionTableLen = iter.nextU2ToInt();

		if (exceptionTableLen > 0){
			String exTable = iter.nextUxToHexString(exceptionTableLen);
			System.out.println("Encountered exception table, just ignore!");
		}

		// 处理子属性
		int subAttrCount = iter.nextU2ToInt();
		for (int i = 1; i <= subAttrCount; i++) {
			int suAttrIndex = iter.nextU2ToInt();
			String subAttrName = clzFile.getConstantPool().getUTF8String(suAttrIndex);

			iter.back(2);// 便于在子属性中获取 attrNameIndex

			if (AttributeInfo.LINE_NUM_TABLE.equalsIgnoreCase(subAttrName)){
				LineNumberTable lineNumberTable = LineNumberTable.parse(iter);
				codeAttr.setLineNumberTable(lineNumberTable);
			}else if (AttributeInfo.LOCAL_VAR_TABLE.equalsIgnoreCase(subAttrName)){
				LocalVariableTable localVariableTable = LocalVariableTable.parse(iter);
				codeAttr.setLocalVariableTable(localVariableTable);
			}else if (AttributeInfo.STACK_MAP_TABLE.equalsIgnoreCase(subAttrName)){
				StackMapTable stackMapTable = StackMapTable.parse(iter);
				codeAttr.setStackMapTable(stackMapTable);
			}else {
				throw new RuntimeException("Need code to process :" + subAttrName);
			}

		}
		return codeAttr;
	}
	private void setStackMapTable(StackMapTable t) {
		this.stackMapTable = t;
		
	}

	
	
	
	
}