1/*
2 * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package java.security;
27
28import java.io.*;
29import java.security.cert.CertPath;
30
31/**
32 * This class encapsulates information about a code signer.
33 * It is immutable.
34 *
35 * @since 1.5
36 * @author Vincent Ryan
37 */
38
39public final class CodeSigner implements Serializable {
40
41    private static final long serialVersionUID = 6819288105193937581L;
42
43    /**
44     * The signer's certificate path.
45     *
46     * @serial
47     */
48    private CertPath signerCertPath;
49
50    /*
51     * The signature timestamp.
52     *
53     * @serial
54     */
55    private Timestamp timestamp;
56
57    /*
58     * Hash code for this code signer.
59     */
60    private transient int myhash = -1;
61
62    /**
63     * Constructs a CodeSigner object.
64     *
65     * @param signerCertPath The signer's certificate path.
66     *                       It must not be {@code null}.
67     * @param timestamp A signature timestamp.
68     *                  If {@code null} then no timestamp was generated
69     *                  for the signature.
70     * @throws NullPointerException if {@code signerCertPath} is
71     *                              {@code null}.
72     */
73    public CodeSigner(CertPath signerCertPath, Timestamp timestamp) {
74        if (signerCertPath == null) {
75            throw new NullPointerException();
76        }
77        this.signerCertPath = signerCertPath;
78        this.timestamp = timestamp;
79    }
80
81    /**
82     * Returns the signer's certificate path.
83     *
84     * @return A certificate path.
85     */
86    public CertPath getSignerCertPath() {
87        return signerCertPath;
88    }
89
90    /**
91     * Returns the signature timestamp.
92     *
93     * @return The timestamp or {@code null} if none is present.
94     */
95    public Timestamp getTimestamp() {
96        return timestamp;
97    }
98
99    /**
100     * Returns the hash code value for this code signer.
101     * The hash code is generated using the signer's certificate path and the
102     * timestamp, if present.
103     *
104     * @return a hash code value for this code signer.
105     */
106    public int hashCode() {
107        if (myhash == -1) {
108            if (timestamp == null) {
109                myhash = signerCertPath.hashCode();
110            } else {
111                myhash = signerCertPath.hashCode() + timestamp.hashCode();
112            }
113        }
114        return myhash;
115    }
116
117    /**
118     * Tests for equality between the specified object and this
119     * code signer. Two code signers are considered equal if their
120     * signer certificate paths are equal and if their timestamps are equal,
121     * if present in both.
122     *
123     * @param obj the object to test for equality with this object.
124     *
125     * @return true if the objects are considered equal, false otherwise.
126     */
127    public boolean equals(Object obj) {
128        if (obj == null || (!(obj instanceof CodeSigner))) {
129            return false;
130        }
131        CodeSigner that = (CodeSigner)obj;
132
133        if (this == that) {
134            return true;
135        }
136        Timestamp thatTimestamp = that.getTimestamp();
137        if (timestamp == null) {
138            if (thatTimestamp != null) {
139                return false;
140            }
141        } else {
142            if (thatTimestamp == null ||
143                (! timestamp.equals(thatTimestamp))) {
144                return false;
145            }
146        }
147        return signerCertPath.equals(that.getSignerCertPath());
148    }
149
150    /**
151     * Returns a string describing this code signer.
152     *
153     * @return A string comprising the signer's certificate and a timestamp,
154     *         if present.
155     */
156    public String toString() {
157        StringBuilder sb = new StringBuilder();
158        sb.append("(");
159        sb.append("Signer: " + signerCertPath.getCertificates().get(0));
160        if (timestamp != null) {
161            sb.append("timestamp: " + timestamp);
162        }
163        sb.append(")");
164        return sb.toString();
165    }
166
167    // Explicitly reset hash code value to -1
168    private void readObject(ObjectInputStream ois)
169        throws IOException, ClassNotFoundException {
170     ois.defaultReadObject();
171     myhash = -1;
172    }
173}
174