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1   /*
2    * Copyright (c) 2004, 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  package sun.net;
26  
27  import java.net.URL;
28  
29  /**
30   * ProgressSource represents the source of progress changes.
31   *
32   * @author Stanley Man-Kit Ho
33   */
34  public class ProgressSource
35  {
36      public enum State { NEW, CONNECTED, UPDATE, DELETE };
37  
38      // URL
39      private URL url;
40      // URL method
41      private String method;
42      // Content type
43      private String contentType;
44      // bytes read
45      private long progress = 0;
46      // last bytes read
47      private long lastProgress = 0;
48      //bytes expected
49      private long expected = -1;
50      // the last thing to happen with this source
51      private State state;
52      // connect flag
53      private boolean connected = false;
54      // threshold for notification
55      private int threshold = 8192;
56      // progress monitor
57      private ProgressMonitor progressMonitor;
58  
59      /**
60       * Construct progress source object.
61       */
62      public ProgressSource(URL url, String method) {
63          this(url, method, -1);
64      }
65  
66      /**
67       * Construct progress source object.
68       */
69      public ProgressSource(URL url, String method, long expected)  {
70          this.url = url;
71          this.method = method;
72          this.contentType = "content/unknown";
73          this.progress = 0;
74          this.lastProgress = 0;
75          this.expected = expected;
76          this.state = State.NEW;
77          this.progressMonitor = ProgressMonitor.getDefault();
78          this.threshold = progressMonitor.getProgressUpdateThreshold();
79      }
80  
81      public boolean connected() {
82          if (!connected) {
83              connected = true;
84              state = State.CONNECTED;
85              return false;
86          }
87          return true;
88      }
89  
90      /**
91       * Close progress source.
92       */
93      public void close() {
94          state = State.DELETE;
95      }
96  
97      /**
98       * Return URL of progress source.
99       */
100     public URL getURL() {
101         return url;
102     }
103 
104     /**
105      * Return method of URL.
106      */
107     public String getMethod()  {
108         return method;
109     }
110 
111     /**
112      * Return content type of URL.
113      */
114     public String getContentType()  {
115         return contentType;
116     }
117 
118     // Change content type
119     public void setContentType(String ct)  {
120         contentType = ct;
121     }
122 
123     /**
124      * Return current progress.
125      */
126     public long getProgress()  {
127         return progress;
128     }
129 
130     /**
131      * Return expected maximum progress; -1 if expected is unknown.
132      */
133     public long getExpected() {
134         return expected;
135     }
136 
137     /**
138      * Return state.
139      */
140     public State getState() {
141         return state;
142     }
143 
144     /**
145      * Begin progress tracking.
146      */
147     public void beginTracking() {
148         progressMonitor.registerSource(this);
149     }
150 
151     /**
152      * Finish progress tracking.
153      */
154     public void finishTracking() {
155         progressMonitor.unregisterSource(this);
156     }
157 
158     /**
159      * Update progress.
160      */
161     public void updateProgress(long latestProgress, long expectedProgress) {
162         lastProgress = progress;
163         progress = latestProgress;
164         expected = expectedProgress;
165 
166         if (connected() == false)
167             state = State.CONNECTED;
168         else
169             state = State.UPDATE;
170 
171         // The threshold effectively divides the progress into
172         // different set of ranges:
173         //
174         //      Range 0: 0..threshold-1,
175         //      Range 1: threshold .. 2*threshold-1
176         //      ....
177         //      Range n: n*threshold .. (n+1)*threshold-1
178         //
179         // To determine which range the progress belongs to, it
180         // would be calculated as follow:
181         //
182         //      range number = progress / threshold
183         //
184         // Notification should only be triggered when the current
185         // progress and the last progress are in different ranges,
186         // i.e. they have different range numbers.
187         //
188         // Using this range scheme, notification will be generated
189         // only once when the progress reaches each range.
190         //
191         if (lastProgress / threshold != progress / threshold)   {
192             progressMonitor.updateProgress(this);
193         }
194 
195         // Detect read overrun
196         if (expected != -1) {
197             if (progress >= expected && progress != 0)
198                 close();
199         }
200     }
201 
202     public Object clone() throws CloneNotSupportedException {
203         return super.clone();
204     }
205 
206     public String toString()    {
207         return getClass().getName() + "[url=" + url + ", method=" + method + ", state=" + state
208             + ", content-type=" + contentType + ", progress=" + progress + ", expected=" + expected + "]";
209     }
210 }