Java tutorial
/* * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.security; import java.io.*; import java.security.cert.CertPath; /** * This class encapsulates information about a code signer. * It is immutable. * * @since 1.5 * @author Vincent Ryan */ public final class CodeSigner implements Serializable { private static final long serialVersionUID = 6819288105193937581L; /** * The signer's certificate path. * * @serial */ private CertPath signerCertPath; /* * The signature timestamp. * * @serial */ private Timestamp timestamp; /* * Hash code for this code signer. */ private transient int myhash = -1; /** * Constructs a CodeSigner object. * * @param signerCertPath The signer's certificate path. * It must not be {@code null}. * @param timestamp A signature timestamp. * If {@code null} then no timestamp was generated * for the signature. * @throws NullPointerException if {@code signerCertPath} is * {@code null}. */ public CodeSigner(CertPath signerCertPath, Timestamp timestamp) { if (signerCertPath == null) { throw new NullPointerException(); } this.signerCertPath = signerCertPath; this.timestamp = timestamp; } /** * Returns the signer's certificate path. * * @return A certificate path. */ public CertPath getSignerCertPath() { return signerCertPath; } /** * Returns the signature timestamp. * * @return The timestamp or {@code null} if none is present. */ public Timestamp getTimestamp() { return timestamp; } /** * Returns the hash code value for this code signer. * The hash code is generated using the signer's certificate path and the * timestamp, if present. * * @return a hash code value for this code signer. */ public int hashCode() { if (myhash == -1) { if (timestamp == null) { myhash = signerCertPath.hashCode(); } else { myhash = signerCertPath.hashCode() + timestamp.hashCode(); } } return myhash; } /** * Tests for equality between the specified object and this * code signer. Two code signers are considered equal if their * signer certificate paths are equal and if their timestamps are equal, * if present in both. * * @param obj the object to test for equality with this object. * * @return true if the objects are considered equal, false otherwise. */ public boolean equals(Object obj) { if (obj == null || (!(obj instanceof CodeSigner))) { return false; } CodeSigner that = (CodeSigner) obj; if (this == that) { return true; } Timestamp thatTimestamp = that.getTimestamp(); if (timestamp == null) { if (thatTimestamp != null) { return false; } } else { if (thatTimestamp == null || (!timestamp.equals(thatTimestamp))) { return false; } } return signerCertPath.equals(that.getSignerCertPath()); } /** * Returns a string describing this code signer. * * @return A string comprising the signer's certificate and a timestamp, * if present. */ public String toString() { StringBuilder sb = new StringBuilder(); sb.append("("); sb.append("Signer: " + signerCertPath.getCertificates().get(0)); if (timestamp != null) { sb.append("timestamp: " + timestamp); } sb.append(")"); return sb.toString(); } // Explicitly reset hash code value to -1 private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException { ois.defaultReadObject(); myhash = -1; } }