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

   1 // Copyright 2009 Google Inc. All rights reserved.
   2
   3 package com.google.appengine.api.blobstore;
   4
   5 import java.io.IOException;
   6 import java.io.ObjectInputStream;
   7 import java.io.Serializable;
   8 import java.util.Date;
   9
  10 /**
  11  * {@code BlobInfo} contains metadata about a blob. This metadata is gathered by
  12  * parsing the HTTP headers included in the blob upload.
  13  *
  14  * @see <a href="http://tools.ietf.org/html/rfc1867">RFC 1867</a> for
  15  * the specification of HTTP file uploads.
  16  */
  17 public class BlobInfo implements Serializable {
  18   private static final long serialVersionUID = 4530115855912621409L;
  19   private static final String DEFAULT_MD5_HASH = "";
  20   protected final BlobKey blobKey;
  21   protected final String contentType;
  22   protected final Date creation;
  23   protected final String filename;
  24   protected final long size;
  25   protected String md5Hash;
  26
  27   /**
  28    * Creates a {@code BlobInfo} by providing the {@link BlobKey} and all
  29    * associated metadata. This is typically done by the API on the developer's
  30    * behalf.
  31    *
  32    * @param blobKey      the {@link BlobKey} of the Blob.
  33    * @param contentType  the MIME Content-Type provided in the HTTP header during upload of this
  34    *                     Blob.
  35    * @param creation     the time and date the blob was uploaded.
  36    * @param filename     the file included in the Content-Disposition HTTP header during upload of
  37    *                     this Blob.
  38    * @param size         the size in bytes of this Blob.
  39    * @param md5Hash      the md5Hash of this Blob.
  40    */
  41   public BlobInfo(BlobKey blobKey, String contentType, Date creation, String filename,
  42                   long size, String md5Hash) {
  43     if (blobKey == null) {
  44       throw new NullPointerException("blobKey must not be null");
  45     }
  46     if (contentType == null) {
  47       throw new NullPointerException("contentType must not be null");
  48     }
  49     if (creation == null) {
  50       throw new NullPointerException("creation must not be null");
  51     }
  52     if (filename == null) {
  53       throw new NullPointerException("filename must not be null");
  54     }
  55     if (md5Hash == null) {
  56       throw new NullPointerException("md5Hash must not be null");
  57     }
  58
  59     this.blobKey = blobKey;
  60     this.contentType = contentType;
  61     this.creation = creation;
  62     this.filename = filename;
  63     this.size = size;
  64     this.md5Hash = md5Hash;
  65   }
  66
  67   public BlobInfo(BlobKey blobKey, String contentType, Date creation, String filename, long size) {
  68     this(blobKey, contentType, creation, filename, size, DEFAULT_MD5_HASH);
  69   }
  70
  71   /**
  72    * Returns the {@link BlobKey} of the Blob this {@code BlobInfo} describes.
  73    */
  74   public BlobKey getBlobKey() {
  75     return blobKey;
  76   }
  77
  78   /**
  79    * Returns the MIME Content-Type provided in the HTTP header during upload of
  80    * this Blob.
  81    */
  82   public String getContentType() {
  83     return contentType;
  84   }
  85
  86   /**
  87    * Returns the time and date the blob was upload.
  88    */
  89   public Date getCreation() {
  90     return creation;
  91   }
  92
  93   /**
  94    * Returns the file included in the Content-Disposition HTTP header during
  95    * upload of this Blob.
  96    */
  97   public String getFilename() {
  98     return filename;
  99   }
 100
 101   /**
 102    * Returns the size in bytes of this Blob.
 103    */
 104   public long getSize() {
 105     return size;
 106   }
 107
 108   /**
 109    * Returns the md5Hash of this Blob.
 110    */
 111   public String getMd5Hash() {
 112     return md5Hash;
 113   }
 114
 115   @Override
 116   public boolean equals(Object obj) {
 117     if (obj instanceof BlobInfo) {
 118       BlobInfo bi = (BlobInfo) obj;
 119       return blobKey.equals(bi.blobKey) &&
 120           contentType.equals(bi.contentType)
 121           &&
 122           creation.equals(bi.creation) &&
 123           filename.equals(bi.filename) &&
 124           size == bi.size &&
 125           md5Hash.equals(bi.md5Hash);
 126     }
 127     return false;
 128   }
 129
 130   @Override
 131   public int hashCode() {
 132     int hash = 17;
 133     hash = hash * 37 + blobKey.hashCode();
 134     hash = hash * 37 + contentType.hashCode();
 135     hash = hash * 37 + filename.hashCode();
 136     hash = hash * 37 + md5Hash.hashCode();
 137     return hash;
 138   }
 139
 140   @Override
 141   public String toString() {
 142     StringBuilder builder = new StringBuilder();
 143     builder.append("<BlobInfo: ");
 144     builder.append(blobKey);
 145     builder.append(", contentType = ");
 146     builder.append(contentType);
 147     builder.append(", creation = ");
 148     builder.append(creation.toString());
 149     builder.append(", filename = ");
 150     builder.append(filename);
 151     builder.append(", size = ");
 152     builder.append(Long.toString(size));
 153     builder.append(", md5Hash = ");
 154     builder.append(md5Hash);
 155     builder.append(">");
 156     return builder.toString();
 157   }
 158
 159   private void readObject(ObjectInputStream in)
 160       throws IOException, ClassNotFoundException {
 161     in.defaultReadObject();
 162     if (md5Hash == null) {
 163       md5Hash = DEFAULT_MD5_HASH;
 164     }
 165   }
 166 }