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.nio.charset.StandardCharsets;
24 import java.util.Objects;
25
26 /**
27 * UTF8 constant pool entry, used for storing long Strings.
28 */
29 public class CPUTF8 extends ConstantPoolEntry {
30
31 private final String utf8;
32
33 private boolean hashCodeComputed;
34
35 private int cachedHashCode;
36
37 /**
38 * Constructs a new instance.
39 *
40 * @param string a constant pool string.
41 */
42 public CPUTF8(final String string) {
43 this(string, -1);
44 }
45
46 /**
47 * Creates a new instance
48 *
49 * @param string a constant pool string.
50 * @param globalIndex index in CpBands
51 * @throws NullPointerException if utf8 is null.
52 */
53 public CPUTF8(final String string, final int globalIndex) {
54 super(CP_UTF8, globalIndex);
55 this.utf8 = Objects.requireNonNull(string, "utf8");
56 }
57
58 @Override
59 public boolean equals(final Object obj) {
60 if (this == obj) {
61 return true;
62 }
63 if (obj == null || this.getClass() != obj.getClass()) {
64 return false;
65 }
66 final CPUTF8 other = (CPUTF8) obj;
67 return utf8.equals(other.utf8);
68 }
69
70 private void generateHashCode() {
71 hashCodeComputed = true;
72 final int PRIME = 31;
73 cachedHashCode = PRIME + utf8.hashCode();
74 }
75
76 @Override
77 public int hashCode() {
78 if (!hashCodeComputed) {
79 generateHashCode();
80 }
81 return cachedHashCode;
82 }
83
84 /**
85 * Sets the global index.
86 *
87 * @param index the global index.
88 */
89 public void setGlobalIndex(final int index) {
90 globalIndex = index;
91 }
92
93 @Override
94 public String toString() {
95 return StandardCharsets.UTF_8.name() + ":" + utf8;
96 }
97
98 /**
99 * Gets the underlying string.
100 *
101 * @return the underlying string.
102 */
103 public String underlyingString() {
104 return utf8;
105 }
106
107 @Override
108 protected void writeBody(final DataOutputStream dos) throws IOException {
109 dos.writeUTF(utf8);
110 }
111 }