Home | History | Annotate | Download | only in security 
      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 java.security;
     19 
     20 import java.io.Serializable;
     21 import java.security.cert.CertPath;
     22 import java.util.Date;
     23 
     24 /**
     25  * {@code Timestamp} represents a signed time stamp. {@code Timestamp} is
     26  * immutable.
     27  */
     28 public final class Timestamp implements Serializable {
     29 
     30     private static final long serialVersionUID = -5502683707821851294L;
     31 
     32     private Date timestamp;
     33 
     34     private CertPath signerCertPath;
     35 
     36     // Cached hash
     37     private transient int hash;
     38 
     39     /**
     40      * Constructs a new instance of {@code Timestamp} with the specified {@code
     41      * timestamp} and the given certificate path.
     42      *
     43      * @param timestamp
     44      *            date and time.
     45      * @param signerCertPath
     46      *            the certificate path.
     47      * @throws NullPointerException
     48      *             if {@code timestamp} is {@code null} or if {@code
     49      *             signerCertPath} is {@code null}.
     50      */
     51     public Timestamp(Date timestamp, CertPath signerCertPath) {
     52         if (timestamp == null) {
     53             throw new NullPointerException("timestamp == null");
     54         }
     55         if (signerCertPath == null) {
     56             throw new NullPointerException("signerCertPath == null");
     57         }
     58         // Clone timestamp to prevent modifications
     59         this.timestamp = new Date(timestamp.getTime());
     60         this.signerCertPath = signerCertPath;
     61     }
     62 
     63     /**
     64      * Compares the specified object with this {@code Timestamp} for equality
     65      * and returns {@code true} if the specified object is equal, {@code false}
     66      * otherwise. The given object is equal to this {@code Timestamp}, if it is
     67      * an instance of {@code Timestamp}, the two timestamps have an equal date
     68      * and time and their certificate paths are equal.
     69      *
     70      * @param obj
     71      *            object to be compared for equality with this {@code
     72      *            Timestamp}.
     73      * @return {@code true} if the specified object is equal to this {@code
     74      *         Timestamp}, otherwise {@code false}.
     75      * @see #hashCode
     76      */
     77     @Override
     78     public boolean equals(Object obj) {
     79         if (obj == this) {
     80             return true;
     81         }
     82         if (obj instanceof Timestamp) {
     83             Timestamp that = (Timestamp) obj;
     84             return timestamp.equals(that.timestamp)
     85                     && signerCertPath.equals(that.signerCertPath);
     86         }
     87         return false;
     88     }
     89 
     90     /**
     91      * Returns the certificate path of this {@code Timestamp}.
     92      *
     93      * @return the certificate path of this {@code Timestamp}.
     94      */
     95     public CertPath getSignerCertPath() {
     96         return signerCertPath;
     97     }
     98 
     99     /**
    100      * Returns the date and time of this {@code Timestamp}.
    101      *
    102      * @return the date and time of this {@code Timestamp}.
    103      */
    104     public Date getTimestamp() {
    105         return (Date) timestamp.clone();
    106     }
    107 
    108     /**
    109      * Returns the hash code value for this {@code Timestamp}. Returns the same
    110      * hash code for {@code Timestamp}s that are equal to each other as
    111      * required by the general contract of {@link Object#hashCode}.
    112      *
    113      * @return the hash code value for this {@code Timestamp}.
    114      * @see Object#equals(Object)
    115      * @see Timestamp#equals(Object)
    116      */
    117     @Override
    118     public int hashCode() {
    119         if (hash == 0) {
    120             hash = timestamp.hashCode() ^ signerCertPath.hashCode();
    121         }
    122         return hash;
    123     }
    124 
    125     /**
    126      * Returns a string containing a concise, human-readable description of this
    127      * {@code Timestamp}.
    128      *
    129      * @return a printable representation for this {@code Timestamp}.
    130      */
    131     @Override
    132     public String toString() {
    133         StringBuilder buf = new StringBuilder(256);
    134         // Dump only the first certificate
    135         buf.append("Timestamp [").append(timestamp).append(" certPath=");
    136         buf.append(signerCertPath.getCertificates().get(0)).append("]");
    137         return buf.toString();
    138     }
    139 }
    140