jasmparser.java

Java Bytecode Editor 是一个 JAVA 的字节码反汇编和修改器。它可以很方便的修改已经编译成 Class 文件的 JAVA 文件。

/*
 *
 */
package ee.ioc.cs.jbe.browser.codeedit;

import java.util.ArrayList;
import org.apache.bcel.generic.*;
import org.gjt.jclasslib.bytecode.OpcodesUtil;


public class JAsmParser {
	/*
	 * Parses the input code and returns an instructionlist, but also has a
	 * sideeffect: it updates the constant pool on the fly to have the required
	 * constants in the constant pool.
	 */
	private JAsmParseException parseException = new JAsmParseException();

	public InstructionList parse(String code, ConstantPoolGen cpg)
			throws JAsmParseException {
		code = code.replaceAll("\r", "");
		String[] codeLines = code.split("\n");
		if (codeLines.length == 1 && codeLines[0].equals("")) {
			return new InstructionList();
		}
		InstructionList instructions = new InstructionList();
		ArrayList<InstructionHandle> instructionHandleList = new ArrayList<InstructionHandle> ();
		ArrayList<TempSwitchData> lookupSwitches = new ArrayList<TempSwitchData>();
		ArrayList<TempSwitchData>  tableSwitches = new ArrayList<TempSwitchData>();
		ArrayList<BranchPair> branches = new ArrayList<BranchPair>();
		InstructionHandle ih;
		String[] instrElems;
		int codeLength = countLines(codeLines);
		// InstructionHandle[] iha = new InstructionHandle[strt.countTokens()];
		int labels = 0;
		int switchMode = 0; // 0- normal , 1- tableswitch, 2 - lookupswitch
		String fullInstr;
		String instrName;
		TempSwitchData tempSwitch = new TempSwitchData();

		for (int i = 0; i < codeLines.length; i++) {
			fullInstr = codeLines[i];
			//switchmode, 1 denoting tableswitch, 2 lookupswitch
			if (beginsWithWhitespace(fullInstr) && switchMode == 1) {
				boolean isDefault = isDefaultLine(fullInstr.trim());
				if (isDefault) {
					int target = getLookupTarget(fullInstr.trim(), labels,
							codeLength); 
					tempSwitch.getBranchPairs().add(
							new BranchPair(-1, target));
				} else {
					int target = getTableArg(fullInstr.trim(), labels, codeLength);
					tempSwitch.getBranchPairs().add(
							new BranchPair(tempSwitch.getInitialLab(), target));
					tempSwitch.incInitialLab();
				}
				
				

			} else if (beginsWithWhitespace(fullInstr) && switchMode == 2) {

				int target = getLookupTarget(fullInstr.trim(), labels,
						codeLength);
				int value = getLookupSource(fullInstr.trim(), labels);
				tempSwitch.getBranchPairs().add(new BranchPair(value, target));
			} else if (beginsWithWhitespace(fullInstr)) {
						parseException.addError(JAsmParseException.WHITESPACE_ERROR,
								fullInstr, labels-1);
				
			} else {
				if (switchMode == 1) {
					TABLESWITCH ts = new TABLESWITCH();
					ih = instructions.append(ts);
					instructionHandleList.add(ih);
					tempSwitch.setHandle(ih);
					tableSwitches.add(tempSwitch);
					labels++;
					switchMode = 0;
				} else if (switchMode == 2) {
					LOOKUPSWITCH ls = new LOOKUPSWITCH();
					ih = instructions.append(ls);
					instructionHandleList.add(ih);
					tempSwitch.setHandle(ih);
					lookupSwitches.add(tempSwitch);
					labels++;
					switchMode = 0;
				} 

				instrElems = fullInstr.split(" ");
				instrName = instrElems[0].toLowerCase().trim();

				if (instrName.equals("bipush")) {
					byte arg = getSingleByteArg(instrElems, labels);
					ih = instructions.append(new BIPUSH(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("sipush")) {
					short arg = getSingleShortArg(instrElems, labels);
					ih = instructions.append(new SIPUSH(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("iinc")) {
					int arg1 = 0;
					int arg2 = 0;
					try {
						arg1 = Integer.parseInt(instrElems[1]);
						arg2 = Integer.parseInt(instrElems[2]);
					} catch (NumberFormatException nfe) {
						parseException.addError(
								JAsmParseException.INT_REQUIRED, instrElems[0],
								labels);
					} catch (ArrayIndexOutOfBoundsException aobe) {
						parseException.addError(
								JAsmParseException.MISSING_ARGUMENTS,
								instrElems[0], labels);
					}

					ih = instructions.append(new IINC(arg1, arg2));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Class and object operations.
				 */
				else if (instrName.equals("anewarray")) {
					int arg = getClassConstRef(instrElems, cpg, labels);
					ih = instructions.append(new ANEWARRAY(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("checkcast")) {
					int arg = getClassConstRef(instrElems, cpg, labels);
					ih = instructions.append(new CHECKCAST(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("instanceof")) {
					int arg = getClassConstRef(instrElems, cpg, labels);
					ih = instructions.append(new INSTANCEOF(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("new")) {
					int arg = getClassConstRef(instrElems, cpg, labels);
					ih = instructions.append(new NEW(arg));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Invoke instructions
				 */
				else if (instrName.equals("invokevirtual")) {
					int arg = getMethodConstRef(instrElems, cpg, labels);
					ih = instructions.append(new INVOKEVIRTUAL(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("invokestatic")) {
					int arg = getMethodConstRef(instrElems, cpg, labels);

					ih = instructions.append(new INVOKESTATIC(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("invokespecial")) {
					int arg = getMethodConstRef(instrElems, cpg, labels);

					ih = instructions.append(new INVOKESPECIAL(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("invokeinterface")) {
					int arg1 = Integer.parseInt(instrElems[1]);
					int arg2 = Integer.parseInt(instrElems[1]);
					ih = instructions.append(new INVOKEINTERFACE(arg1, arg2));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Field instructions
				 */
				else if (instrName.equals("getstatic")) {
					int arg = getFieldConstRef(instrElems, cpg, labels);

					ih = instructions.append(new GETSTATIC(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("getfield")) {
					int arg = getFieldConstRef(instrElems, cpg, labels);

					ih = instructions.append(new GETFIELD(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("putstatic")) {
					int arg = getFieldConstRef(instrElems, cpg, labels);

					ih = instructions.append(new PUTSTATIC(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("putfield")) {
					int arg = getFieldConstRef(instrElems, cpg, labels);

					ih = instructions.append(new PUTFIELD(arg));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Newarray instructions
				 */
				else if (instrName.equals("newarray")) {
					byte arg = getArrayRef(instrElems, labels);

					ih = instructions.append(new NEWARRAY(arg));
					instructionHandleList.add(ih);
					labels++;
				}

				else if (instrName.equals("multianewarray")) {
					short dim = 1;
					int arg = 0;
					try {
						dim = Short.parseShort(instrElems[2]);
					} catch (NumberFormatException nfe) {
						parseException.addError(
								JAsmParseException.SHORT_REQUIRED,
								instrElems[0], labels);
					} catch (ArrayIndexOutOfBoundsException aobe) {
						parseException.addError(
								JAsmParseException.MISSING_ARGUMENTS,
								instrElems[0], labels);
					}

					try {
						arg = Integer.parseInt(instrElems[1]);
					} catch (NumberFormatException nfe) {
						String classN = instrElems[1];
						arg = cpg.addClass(classN);
					} catch (ArrayIndexOutOfBoundsException aobe) {
						parseException.addError(
								JAsmParseException.MISSING_ARGUMENTS,
								instrElems[0], labels);
					}

					ih = instructions.append(new MULTIANEWARRAY(arg, dim));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Load constant instructions
				 */
				else if (instrName.equals("ldc")) {
					int arg = getConstRef4ldc(instrElems, cpg, labels);
					ih = instructions.append(new LDC(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("ldc_w")) {
					int arg = getConstRef4ldc(instrElems, cpg, labels);
					ih = instructions.append(new LDC_W(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("ldc2_w")) {
					int arg = getConstRefldc2_w(instrElems, cpg, labels);
					ih = instructions.append(new LDC2_W(arg));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Local Variable instructions
				 */
				else if (instrName.equals("ret")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new RET(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aload")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new ALOAD(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("astore")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new ASTORE(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("dload")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new DLOAD(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("dstore")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new DSTORE(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("fload")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new FLOAD(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("fstore")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new FSTORE(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("iload")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new ILOAD(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("istore")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new ISTORE(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("lload")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new LLOAD(arg));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("lstore")) {
					int arg = getSingleIntArg(instrElems, labels);
					ih = instructions.append(new LSTORE(arg));
					instructionHandleList.add(ih);
					labels++;
				}
				/*
				 * Switch instructions
				 */
				else if (instrName.equals("tableswitch")) {
					switchMode = 1;
					int arg = getSingleIntArg(instrElems, labels);
					tempSwitch = new TempSwitchData(2, arg);
				} else if (instrName.equals("lookupswitch")) {
					switchMode = 2;
					tempSwitch = new TempSwitchData(1);
				}

				/*
				 * 0 parameter instructions
				 */
				else if (instrName.equals("aaload")) {
					ih = instructions.append(new AALOAD());
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aastore")) {
					ih = instructions.append(new AASTORE());
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aconst_null")) {
					ih = instructions.append(new ACONST_NULL());
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aload_0")) {
					ih = instructions.append(new ALOAD(0));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aload_1")) {
					ih = instructions.append(new ALOAD(1));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aload_2")) {
					ih = instructions.append(new ALOAD(2));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("aload_3")) {
					ih = instructions.append(new ALOAD(3));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("areturn")) {
					ih = instructions.append(new ARETURN());
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("arraylength")) {
					ih = instructions.append(new ARRAYLENGTH());
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("astore_0")) {
					ih = instructions.append(new ASTORE(0));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("astore_1")) {
					ih = instructions.append(new ASTORE(1));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("astore_2")) {
					ih = instructions.append(new ASTORE(2));
					instructionHandleList.add(ih);
					labels++;
				} else if (instrName.equals("astore_3")) {
					ih = instructions.append(new ASTORE(3));