org.objectweb.asm.Opcodes# TABLESWITCH 源码实例Demo

public InsnValue getSwitchValue(AbstractInsnNode insn, InsnValue value) {
	if (value.getValue() == null) {
		return InsnValue.intValue(-1);
	}
	int i = (int) value.getValue();
	switch (insn.getOpcode()) {
	case Opcodes.TABLESWITCH:
		TableSwitchInsnNode tsin = (TableSwitchInsnNode) insn;
		if (i < tsin.min || i > tsin.max) {
			return InsnValue.intValue(-1);
		}
		return InsnValue.intValue(i);
	case Opcodes.LOOKUPSWITCH:
		LookupSwitchInsnNode lsin = (LookupSwitchInsnNode) insn;
		for (Object o : lsin.keys) {
			if (o.equals(i)) {
				return InsnValue.intValue(i);
			}
		}
		return InsnValue.intValue(-1);
	}

	return null;
}
 

/**
 * <p>
 * This method finds Switch block in a method and processes it
 * </p>.
 *
 * @param scanStartIndex Start index for the scan
 * @param scanEndIndex End index for the scan
 */
private void instrumentswitchBlock(int scanStartIndex,
		int scanEndIndex) {
	for (scanIndexForswitch = scanStartIndex; scanIndexForswitch <= scanEndIndex; scanIndexForswitch++) {
		AbstractInsnNode currentInsnNode = insnArr[scanIndexForswitch];

		if (currentInsnNode instanceof TableSwitchInsnNode
				&& Opcodes.TABLESWITCH == currentInsnNode.getOpcode()) {
			processTableSwitchBlock((TableSwitchInsnNode) currentInsnNode);
		} else if (currentInsnNode instanceof LookupSwitchInsnNode
				&& Opcodes.LOOKUPSWITCH == currentInsnNode.getOpcode()) {
			processLookupSwitchBlock((LookupSwitchInsnNode) currentInsnNode);
		}

	}
}
 

@Test
public void test_checkTableSwitch() throws Exception {
    List<BasicBlock> hashCodeBlocks = METHOD_BLOCKS.get("checkTableSwitch(I)I");
    int[][] expectedHashCodeBlocks = new int[][]{
            {Opcodes.ICONST_5, Opcodes.ISTORE, Opcodes.ILOAD, Opcodes.TABLESWITCH},
            {Opcodes.ICONST_1, Opcodes.ISTORE, Opcodes.GOTO},
            {Opcodes.ICONST_2, Opcodes.ISTORE, Opcodes.GOTO},
            {Opcodes.ICONST_3, Opcodes.ISTORE, Opcodes.GOTO},
            {Opcodes.ICONST_0, Opcodes.ISTORE},
            {Opcodes.ILOAD, Opcodes.IRETURN},
    };
    int[][] expectedSwitchCounts = new int[][]{
        {4},
        {},
        {},
        {},
        {},
        {},
    };
    
    // Verify the shape of the blocks.
    boolean didMatch = compareBlocks(expectedHashCodeBlocks, hashCodeBlocks);
    Assert.assertTrue(didMatch);
    
    // Verify the switch option value.
    didMatch = compareSwitches(expectedSwitchCounts, hashCodeBlocks);
    Assert.assertTrue(didMatch);
}
 

@Override
public final void visitTableSwitchInsn(final int min, final int max, final Label dflt, final Label... labels) {
  AttributesImpl attrs = new AttributesImpl();
  attrs.addAttribute("", "min", "min", "", Integer.toString(min));
  attrs.addAttribute("", "max", "max", "", Integer.toString(max));
  attrs.addAttribute("", "dflt", "dflt", "", getLabel(dflt));
  String o = Printer.OPCODES[Opcodes.TABLESWITCH];
  sa.addStart(o, attrs);
  for (int i = 0; i < labels.length; i++) {
    AttributesImpl att2 = new AttributesImpl();
    att2.addAttribute("", "name", "name", "", getLabel(labels[i]));
    sa.addElement("label", att2);
  }
  sa.addEnd(o);
}
 

public SwitchInstruction(Label dflt, int[] keys, Label[] labels) {
    super(Opcodes.TABLESWITCH);
    this.dflt = dflt;
    this.keys = keys;
    this.labels = labels;
    for(int iter = 0 ; iter < keys.length ; iter++) {
        LabelInstruction.labelIsUsed(labels[iter]);
    }
    LabelInstruction.labelIsUsed(dflt);
}
 

public TableSwitchInsnNode() {
  super(Opcodes.TABLESWITCH);
  labels = new ArrayList<>();
}
 

/**
 * Constructs a new {@link TableSwitchInsnNode}.
 *
 * @param min
 *          the minimum key value.
 * @param max
 *          the maximum key value.
 * @param dflt
 *          beginning of the default handler block.
 * @param labels
 *          beginnings of the handler blocks. {@code labels[i]} is the beginning of the handler block for the {@code min + i} key.
 */
public TableSwitchInsnNode(final int min, final int max, final LabelNode dflt, final LabelNode... labels) {
	super(Opcodes.TABLESWITCH);
	this.min = min;
	this.max = max;
	this.dflt = dflt;
	this.labels = Util.asArrayList(labels);
}
 

/**
 * Constructs a new {@link TableSwitchInsnNode}.
 *
 * @param min the minimum key value.
 * @param max the maximum key value.
 * @param dflt beginning of the default handler block.
 * @param labels beginnings of the handler blocks. {@code labels[i]} is the beginning of the
 *     handler block for the {@code min + i} key.
 */
public TableSwitchInsnNode(
    final int min, final int max, final LabelNode dflt, final LabelNode... labels) {
  super(Opcodes.TABLESWITCH);
  this.min = min;
  this.max = max;
  this.dflt = dflt;
  this.labels = Util.asArrayList(labels);
}
 

/**
 * Constructs a new {@link TableSwitchInsnNode}.
 * 
 * @param min
 *          the minimum key value.
 * @param max
 *          the maximum key value.
 * @param dflt
 *          beginning of the default handler block.
 * @param labels
 *          beginnings of the handler blocks. <tt>labels[i]</tt> is the
 *          beginning of the handler block for the <tt>min + i</tt> key.
 */
public TableSwitchInsnNode(final int min, final int max, final LabelNode dflt, final LabelNode... labels) {
  super(Opcodes.TABLESWITCH);
  this.min = min;
  this.max = max;
  this.dflt = dflt;
  this.labels = new ArrayList<LabelNode>();
  if (labels != null) {
    this.labels.addAll(Arrays.asList(labels));
  }
}
 

/**
 * Constructs a new {@link TableSwitchInsnNode}.
 *
 * @param min the minimum key value.
 * @param max the maximum key value.
 * @param dflt beginning of the default handler block.
 * @param labels beginnings of the handler blocks. {@code labels[i]} is the beginning of the
 *     handler block for the {@code min + i} key.
 */
public TableSwitchInsnNode(
    final int min, final int max, final LabelNode dflt, final LabelNode... labels) {
  super(Opcodes.TABLESWITCH);
  this.min = min;
  this.max = max;
  this.dflt = dflt;
  this.labels = Util.asArrayList(labels);
}
 

/**
 * Constructs a new {@link TableSwitchInsnNode}.
 *
 * @param min the minimum key value.
 * @param max the maximum key value.
 * @param dflt beginning of the default handler block.
 * @param labels beginnings of the handler blocks. {@code labels[i]} is the beginning of the
 *     handler block for the {@code min + i} key.
 */
public TableSwitchInsnNode(
    final int min, final int max, final LabelNode dflt, final LabelNode... labels) {
  super(Opcodes.TABLESWITCH);
  this.min = min;
  this.max = max;
  this.dflt = dflt;
  this.labels = Util.asArrayList(labels);
}