java/src/main/com/google/appengine/api/blobstore/BlobKey.java

   1 // Copyright 2009 Google Inc. All rights reserved.
   2
   3 package com.google.appengine.api.blobstore;
   4
   5 import java.io.Serializable;
   6
   7 /**
   8  * {@code BlobKey} contains the string identifier of a large (possibly
   9  * larger than 1MB) blob of binary data that was uploaded in a
  10  * previous request and can be streamed directly to users.
  11  *
  12  */
  13 public final class BlobKey implements Serializable, Comparable<BlobKey> {
  14   private final String blobKey;
  15
  16   /**
  17    * Construct a new {@code BlobKey} with the specified key string.
  18    *
  19    * @throws IllegalArgumentException If the specified string was null.
  20    */
  21   public BlobKey(String blobKey) {
  22     if (blobKey == null) {
  23       throw new IllegalArgumentException("Argument must not be null.");
  24     }
  25     this.blobKey = blobKey;
  26   }
  27
  28   /**
  29    * Returns the blob key as a String.
  30    */
  31   public String getKeyString() {
  32     return blobKey;
  33   }
  34
  35   @Override
  36   public int hashCode() {
  37     return blobKey.hashCode();
  38   }
  39
  40   /**
  41    * Two {@code BlobKey} objects are considered equal if they point
  42    * to the same blobs.
  43    */
  44   @Override
  45   public boolean equals(Object object) {
  46     if (object instanceof BlobKey) {
  47       BlobKey key = (BlobKey) object;
  48       return key.blobKey.equals(blobKey);
  49     }
  50     return false;
  51   }
  52
  53   @Override
  54   public String toString() {
  55     return "<BlobKey: " + blobKey + ">";
  56   }
  57
  58   public int compareTo(BlobKey o) {
  59     return blobKey.compareTo(o.blobKey);
  60   }
  61 }