1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * https://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.commons.compress.harmony.unpack200.bytecode;
20
21 import java.io.DataOutputStream;
22 import java.io.IOException;
23 import java.util.List;
24
25 /**
26 * An entry in an exception table.
27 */
28 public class ExceptionTableEntry {
29
30 private final int startPC;
31 private final int endPC;
32 private final int handlerPC;
33 private final CPClass catchType;
34
35 private int startPcRenumbered;
36 private int endPcRenumbered;
37 private int handlerPcRenumbered;
38 private int catchTypeIndex;
39
40 /**
41 * Constructs a new ExceptionTableEntry. Exception tables are of two kinds: either a normal one (with a Throwable as the catchType) or a finally clause
42 * (which has no catchType). In the class file, the finally clause is represented as catchType == 0.
43 *
44 * To create a finally clause with this method, pass in null for the catchType.
45 *
46 * @param startPC int
47 * @param endPC int
48 * @param handlerPC int
49 * @param catchType CPClass (if it's a normal catch) or null (if it's a finally clause).
50 */
51 public ExceptionTableEntry(final int startPC, final int endPC, final int handlerPC, final CPClass catchType) {
52 this.startPC = startPC;
53 this.endPC = endPC;
54 this.handlerPC = handlerPC;
55 this.catchType = catchType;
56 }
57
58 public CPClass getCatchType() {
59 return catchType;
60 }
61
62 public void renumber(final List<Integer> byteCodeOffsets) {
63 startPcRenumbered = byteCodeOffsets.get(startPC).intValue();
64 final int endPcIndex = startPC + endPC;
65 endPcRenumbered = byteCodeOffsets.get(endPcIndex).intValue();
66 final int handlerPcIndex = endPcIndex + handlerPC;
67 handlerPcRenumbered = byteCodeOffsets.get(handlerPcIndex).intValue();
68 }
69
70 public void resolve(final ClassConstantPool pool) {
71 if (catchType == null) {
72 // If the catch type is a finally clause
73 // the index is always 0.
74 catchTypeIndex = 0;
75 return;
76 }
77 catchType.resolve(pool);
78 catchTypeIndex = pool.indexOf(catchType);
79 }
80
81 public void write(final DataOutputStream dos) throws IOException {
82 dos.writeShort(startPcRenumbered);
83 dos.writeShort(endPcRenumbered);
84 dos.writeShort(handlerPcRenumbered);
85 dos.writeShort(catchTypeIndex);
86 }
87 }