JVM第7次作业

group06/1378560653/mini-jvm/com/coderising/jvm/attr/ConstantValue.java

@@ -0,0 +1,21 @@
+package com.coderising.jvm.attr;
+
+public class ConstantValue extends AttributeInfo {
+
+	private int constValueIndex;
+
+	public ConstantValue(int attrNameIndex, int attrLen) {
+		super(attrNameIndex, attrLen);		
+	}
+
+
+	public int getConstValueIndex() {
+		return constValueIndex;
+	}
+	public void setConstValueIndex(int constValueIndex) {
+		this.constValueIndex = constValueIndex;
+	}
+
+
+
+}

group06/1378560653/mini-jvm/com/coderising/jvm/cmd/ByteCodeCommand.java

@@ -55,6 +55,10 @@ public abstract class ByteCodeCommand {
 	static{
 		codeMap.put("01", "aconst_null");
 
+		codeMap.put("A2", "if_icmp_ge");
+		codeMap.put("A4", "if_icmple");
+		codeMap.put("A7", "goto");
+
 		codeMap.put("BB", "new");
 		codeMap.put("37", "lstore");
 		codeMap.put("B7", "invokespecial");
@@ -149,4 +153,4 @@ public String getReadableCodeText(){
 	}
 
 	public abstract void execute(StackFrame frame,ExecutionResult result);
-}
+}

group06/1378560653/mini-jvm/com/coderising/jvm/cmd/CommandParser.java

@@ -7,123 +7,107 @@
 
 public class CommandParser {
 
-	public static final String aconst_null = "01";
-	public static final String new_object = "BB";
-	public static final String lstore = "37";
-	public static final String invokespecial = "B7";
-	public static final String invokevirtual = "B6";
-	public static final String getfield = "B4";
-	public static final String putfield = "B5";
-	public static final String getstatic = "B2";
-	public static final String ldc = "12";
-	public static final String dup = "59";
-	public static final String bipush = "10";
-	public static final String aload_0 = "2A";
-	public static final String aload_1 = "2B";
-	public static final String aload_2 = "2C";
-	public static final String iload = "15";
-	public static final String iload_1 = "1B";
-	public static final String iload_2 = "1C";
-	public static final String iload_3 = "1D";
-	public static final String fload_3 = "25";
-
-	public static final String voidreturn = "B1";
-	public static final String ireturn = "AC";
-	public static final String freturn = "AE";
-
-	public static final String astore_1 = "4C";
-	public static final String if_icmp_ge = "A2";
-	public static final String if_icmple = "A4";
-	public static final String goto_no_condition = "A7";
-	public static final String iconst_0 = "03";
-	public static final String iconst_1 = "04";
-	public static final String istore_1 = "3C";
-	public static final String istore_2 = "3D";
-	public static final String iadd = "60";
-	public static final String iinc = "84";
+
 
 	public static ByteCodeCommand[] parse(ClassFile clzFile, String codes) {
-		if((codes == null) || (codes.length() == 0) || (codes.length() % 2 )!=0 ) {
-			throw new RuntimeException("the original code is not correct.");
-		} //为什么必须是偶数呢？
-
+
+		if ((codes == null) || (codes.length() == 0) || (codes.length() % 2) != 0) {
+			throw new RuntimeException("the orignal code is not correct");
+
+		}
+
 		codes = codes.toUpperCase();
-		
-		CommandIterator iter = new CommandIterator(codes); //iter是codes的一个迭代器
+
+		CommandIterator iter = new CommandIterator(codes);
 		List<ByteCodeCommand> cmds = new ArrayList<ByteCodeCommand>();
-		
-		while(iter.hasNext()){
+
+		while (iter.hasNext()) {
 			String opCode = iter.next2CharAsString();
-			
-			if(opCode.equals(new_object)){
+
+			if (ByteCodeCommand.new_object.equals(opCode)) {
 				NewObjectCmd cmd = new NewObjectCmd(clzFile, opCode);
-				
+
 				cmd.setOprand1(iter.next2CharAsInt());
 				cmd.setOprand2(iter.next2CharAsInt());
-				
+
 				cmds.add(cmd);
-			} else if (opCode.equals(invokespecial)){
+			} else if (ByteCodeCommand.invokespecial.equals(opCode)) {
 				InvokeSpecialCmd cmd = new InvokeSpecialCmd(clzFile, opCode);
-
 				cmd.setOprand1(iter.next2CharAsInt());
 				cmd.setOprand2(iter.next2CharAsInt());
-
+				// System.out.println( cmd.toString(clzFile.getConstPool()));
 				cmds.add(cmd);
-			} else if (opCode.equals(invokevirtual)){
+			} else if (ByteCodeCommand.invokevirtual.equals(opCode)) {
 				InvokeVirtualCmd cmd = new InvokeVirtualCmd(clzFile, opCode);
-
 				cmd.setOprand1(iter.next2CharAsInt());
 				cmd.setOprand2(iter.next2CharAsInt());
-				
+
 				cmds.add(cmd);
-			} else if (opCode.equals(getfield)){
+			} else if (ByteCodeCommand.getfield.equals(opCode)) {
 				GetFieldCmd cmd = new GetFieldCmd(clzFile, opCode);
-
 				cmd.setOprand1(iter.next2CharAsInt());
 				cmd.setOprand2(iter.next2CharAsInt());
-
 				cmds.add(cmd);
-			} else if (opCode.equals(getstatic)){
+			} else if (ByteCodeCommand.getstatic.equals(opCode)) {
 				GetStaticFieldCmd cmd = new GetStaticFieldCmd(clzFile, opCode);
-
 				cmd.setOprand1(iter.next2CharAsInt());
 				cmd.setOprand2(iter.next2CharAsInt());
-
 				cmds.add(cmd);
-			} else if (opCode.equals(putfield)){
+			} else if (ByteCodeCommand.putfield.equals(opCode)) {
 				PutFieldCmd cmd = new PutFieldCmd(clzFile, opCode);
-
 				cmd.setOprand1(iter.next2CharAsInt());
 				cmd.setOprand2(iter.next2CharAsInt());
-
 				cmds.add(cmd);
-			}	else if (opCode.equals(ldc)){
+			} else if (ByteCodeCommand.ldc.equals(opCode)) {
 				LdcCmd cmd = new LdcCmd(clzFile, opCode);
-
 				cmd.setOperand(iter.next2CharAsInt());
-
 				cmds.add(cmd);
-			} else if (opCode.equals(bipush)){
+			} else if (ByteCodeCommand.bipush.equals(opCode)) {
 				BiPushCmd cmd = new BiPushCmd(clzFile, opCode);
-
 				cmd.setOperand(iter.next2CharAsInt());
-
 				cmds.add(cmd);
-			} else if (dup.equals(opCode) || aload_0.equals(opCode) || aload_1.equals(opCode) || aload_2.equals(opCode)
-					|| iload_1.equals(opCode) || iload_2.equals(opCode) || iload_3.equals(opCode)
-					|| fload_3.equals(opCode) || voidreturn.equals(opCode) || astore_1.equals(opCode)) {
-
+			}else if(ByteCodeCommand.if_icmp_ge.equals(opCode) 
+					|| ByteCodeCommand.if_icmple.equals(opCode) 
+					|| ByteCodeCommand.goto_no_condition.equals(opCode)){
+				ComparisonCmd cmd = new ComparisonCmd(clzFile,opCode);
+				cmd.setOprand1(iter.next2CharAsInt());
+				cmd.setOprand2(iter.next2CharAsInt());
+				cmds.add(cmd);
+			} else if(ByteCodeCommand.iinc.equals(opCode)){
+				IncrementCmd cmd = new IncrementCmd(clzFile,opCode);
+				cmd.setOprand1(iter.next2CharAsInt());
+				cmd.setOprand2(iter.next2CharAsInt());
+				cmds.add(cmd);
+			}
+			else if (ByteCodeCommand.dup.equals(opCode) 
+					|| ByteCodeCommand.aload_0.equals(opCode) 
+					|| ByteCodeCommand.aload_1.equals(opCode) 
+					|| ByteCodeCommand.aload_2.equals(opCode)
+					|| ByteCodeCommand.iload_1.equals(opCode) 
+					|| ByteCodeCommand.iload_2.equals(opCode) 
+					|| ByteCodeCommand.iload_3.equals(opCode)
+					|| ByteCodeCommand.fload_3.equals(opCode) 
+					|| ByteCodeCommand.iconst_0.equals(opCode)
+					|| ByteCodeCommand.iconst_1.equals(opCode)
+					|| ByteCodeCommand.istore_1.equals(opCode)
+					|| ByteCodeCommand.istore_2.equals(opCode)
+					|| ByteCodeCommand.voidreturn.equals(opCode) 
+					|| ByteCodeCommand.iadd.equals(opCode)
+					|| ByteCodeCommand.astore_1.equals(opCode)
+					|| ByteCodeCommand.ireturn.equals(opCode)) {
+
 				NoOperandCmd cmd = new NoOperandCmd(clzFile, opCode);
 				cmds.add(cmd);
 			} else {
-				throw new RuntimeException("sorry, the java instruction "+opCode+"has not been implemented.");
+				throw new RuntimeException("Sorry, the java instruction " + opCode + " has not been implemented");
 			}
+
 		}
-		
+
 		calcuateOffset(cmds);
-		
+
 		ByteCodeCommand[] result = new ByteCodeCommand[cmds.size()];
-		cmds.toArray(result); //list.toArray(array);
+		cmds.toArray(result);
 		return result;
 	}
 
@@ -161,4 +145,4 @@ public int next2CharAsInt() {
 		}
 
 	}
-}
+}

group06/1378560653/mini-jvm/com/coderising/jvm/cmd/ComparisonCmd.java

@@ -0,0 +1,78 @@
+package com.coderising.jvm.cmd;
+
+import com.coderising.jvm.clz.ClassFile;
+import com.coderising.jvm.engine.ExecutionResult;
+import com.coderising.jvm.engine.JavaObject;
+import com.coderising.jvm.engine.StackFrame;
+
+public class ComparisonCmd extends TwoOperandCmd {
+
+	protected ComparisonCmd(ClassFile clzFile, String opCode) {
+		super(clzFile, opCode);
+
+	}
+
+
+	@Override
+	public void execute(StackFrame frame,ExecutionResult result) {		
+
+		if(ByteCodeCommand.if_icmp_ge.equals(this.getOpCode())){
+			//注意次序
+			JavaObject jo2 = frame.getOprandStack().pop();
+			JavaObject jo1 = frame.getOprandStack().pop();
+
+			if(jo1.getIntValue() >= jo2.getIntValue()){
+
+				this.setJumpResult(result);
+
+			}
+
+		} else if(ByteCodeCommand.if_icmple.equals(this.getOpCode())){
+			//注意次序
+			JavaObject jo2 = frame.getOprandStack().pop();
+			JavaObject jo1 = frame.getOprandStack().pop();
+
+			if(jo1.getIntValue() <= jo2.getIntValue()){
+				this.setJumpResult(result);
+			}
+
+		} else if(ByteCodeCommand.goto_no_condition.equals(this.getOpCode())){
+			this.setJumpResult(result);
+
+		} else{
+			throw new RuntimeException(this.getOpCode() + "has not been implemented");
+		}
+
+
+
+
+	}
+
+	private int getOffsetFromStartCmd(){
+		//If the comparison succeeds, the unsigned branchbyte1 and branchbyte2
+		//are used to construct a signed 16-bit offset, where the offset is calculated
+		//to be (branchbyte1 << 8) | branchbyte2. Execution then proceeds at that
+		//offset from the address of the opcode of this if_icmp<cond> instruction
+
+
+		int index1 = this.getOprand1();
+		int index2 = this.getOprand2();
+		short offsetFromCurrent = (short)(index1 << 8 | index2);				
+		return this.getOffset() + offsetFromCurrent ;
+	}
+	private void setJumpResult(ExecutionResult result){
+
+		int offsetFromStartCmd = this.getOffsetFromStartCmd();		
+
+		result.setNextAction(ExecutionResult.JUMP);
+		result.setNextCmdOffset(offsetFromStartCmd);
+	}
+
+	@Override
+	public String toString() {
+		int index = this.getIndex();
+		String text = this.getReadableCodeText();
+		return this.getOffset()+":"+ this.getOpCode() + " "+text + " " + this.getOffsetFromStartCmd();
+	}
+
+}

group06/1378560653/mini-jvm/com/coderising/jvm/cmd/IncrementCmd.java

@@ -0,0 +1,38 @@
+package com.coderising.jvm.cmd;
+
+import com.coderising.jvm.clz.ClassFile;
+import com.coderising.jvm.engine.ExecutionResult;
+import com.coderising.jvm.engine.Heap;
+import com.coderising.jvm.engine.JavaObject;
+import com.coderising.jvm.engine.StackFrame;
+
+public class IncrementCmd extends TwoOperandCmd {
+
+	public IncrementCmd(ClassFile clzFile, String opCode) {
+		super(clzFile, opCode);
+
+	}
+
+	@Override
+	public String toString() {
+
+		return this.getOffset()+":"+this.getOpCode()+ " " +this.getReadableCodeText();
+	}
+
+	@Override
+	public void execute(StackFrame frame, ExecutionResult result) {
+
+		int index = this.getOprand1();
+
+		int constValue = this.getOprand2();
+
+		int currentValue = frame.getLocalVariableValue(index).getIntValue();
+
+		JavaObject jo = Heap.getInstance().newInt(constValue+currentValue);
+
+		frame.setLocalVariableValue(index, jo);
+
+
+	}
+
+}