1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.bcel.classfile;
19
20 import java.io.DataInput;
21 import java.io.DataOutputStream;
22 import java.io.IOException;
23
24 import org.apache.bcel.Const;
25
26 /**
27 * This class represents an entry in the exports table of the Module attribute. Each entry describes a package which may
28 * open the parent module.
29 *
30 * @see Module
31 * @since 6.4.0
32 */
33 public final class ModuleExports implements Cloneable, Node {
34
35 private final int exportsIndex; // points to CONSTANT_Package_info
36 private final int exportsFlags;
37 private final int exportsToCount;
38 private final int[] exportsToIndex; // points to CONSTANT_Module_info
39
40 /**
41 * Constructs object from file stream.
42 *
43 * @param file Input stream
44 * @throws IOException if an I/O Exception occurs in readUnsignedShort
45 */
46 ModuleExports(final DataInput file) throws IOException {
47 exportsIndex = file.readUnsignedShort();
48 exportsFlags = file.readUnsignedShort();
49 exportsToCount = file.readUnsignedShort();
50 exportsToIndex = new int[exportsToCount];
51 for (int i = 0; i < exportsToCount; i++) {
52 exportsToIndex[i] = file.readUnsignedShort();
53 }
54 }
55
56 /**
57 * Called by objects that are traversing the nodes of the tree implicitly defined by the contents of a Java class.
58 * I.e., the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
59 *
60 * @param v Visitor object
61 */
62 @Override
63 public void accept(final Visitor v) {
64 v.visitModuleExports(this);
65 }
66
67 // TODO add more getters and setters?
68
69 /**
70 * @return deep copy of this object
71 */
72 public ModuleExports copy() {
73 try {
74 return (ModuleExports) clone();
75 } catch (final CloneNotSupportedException e) {
76 // TODO should this throw?
77 }
78 return null;
79 }
80
81 /**
82 * Dump table entry to file stream in binary format.
83 *
84 * @param file Output file stream
85 * @throws IOException if an I/O Exception occurs in writeShort
86 */
87 public void dump(final DataOutputStream file) throws IOException {
88 file.writeShort(exportsIndex);
89 file.writeShort(exportsFlags);
90 file.writeShort(exportsToCount);
91 for (final int entry : exportsToIndex) {
92 file.writeShort(entry);
93 }
94 }
95
96 /**
97 * @return String representation
98 */
99 @Override
100 public String toString() {
101 return "exports(" + exportsIndex + ", " + exportsFlags + ", " + exportsToCount + ", ...)";
102 }
103
104 /**
105 * @return Resolved string representation
106 */
107 public String toString(final ConstantPool constantPool) {
108 final StringBuilder buf = new StringBuilder();
109 final String packageName = constantPool.constantToString(exportsIndex, Const.CONSTANT_Package);
110 buf.append(Utility.compactClassName(packageName, false));
111 buf.append(", ").append(String.format("%04x", exportsFlags));
112 buf.append(", to(").append(exportsToCount).append("):\n");
113 for (final int index : exportsToIndex) {
114 final String moduleName = constantPool.getConstantString(index, Const.CONSTANT_Module);
115 buf.append(" ").append(Utility.compactClassName(moduleName, false)).append("\n");
116 }
117 return buf.substring(0, buf.length() - 1); // remove the last newline
118 }
119 }