001: /*
002: * $Header: /export/home/cvsroot/MyPersonalizerRepository/MyPersonalizer/Subsystems/Portal/Sources/es/udc/mypersonalizer/portal/controller/services/ServiceReplyCatcherThread.java,v 1.1.1.1 2004/03/25 12:08:39 fbellas Exp $
003: * $Revision: 1.1.1.1 $
004: * $Date: 2004/03/25 12:08:39 $
005: *
006: * =============================================================================
007: *
008: * Copyright (c) 2003, The MyPersonalizer Development Group
009: * (http://www.tic.udc.es/~fbellas/mypersonalizer/index.html) at
010: * University Of A Coruna
011: * All rights reserved.
012: *
013: * Redistribution and use in source and binary forms, with or without
014: * modification, are permitted provided that the following conditions are met:
015: *
016: * - Redistributions of source code must retain the above copyright notice,
017: * this list of conditions and the following disclaimer.
018: *
019: * - Redistributions in binary form must reproduce the above copyright notice,
020: * this list of conditions and the following disclaimer in the documentation
021: * and/or other materials provided with the distribution.
022: *
023: * - Neither the name of the University Of A Coruna nor the names of its
024: * contributors may be used to endorse or promote products derived from
025: * this software without specific prior written permission.
026: *
027: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
028: * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
029: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
030: * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
031: * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
032: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
033: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
034: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
035: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
036: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
037: * POSSIBILITY OF SUCH DAMAGE.
038: *
039: */
040:
041: package es.udc.mypersonalizer.portal.controller.services;
042:
043: import java.io.BufferedReader;
044: import java.io.InputStream;
045: import java.io.InputStreamReader;
046: import java.io.IOException;
047: import java.net.URL;
048:
049: /**
050: * This class gets the content of an URL. There is a time limit to get it. A
051: * sample code to use it follows:
052: * <p>
053: * <code>
054: * URL url = new URL("http://www.yahoo.com");<br>
055: * <b>ServiceReplyCatcher catcher = new ServiceReplyCatcher(url);</b><br>
056: * System.out.println("Contacting: " + url);<br>
057: * <b>catcher.start();</b><br>
058: * <br>
059: * try {<br>
060: * <b>catcher.join(timeOut);</b><br>
061: * } catch (InterruptedException e) {<br>
062: * e.printStackTrace();<br>
063: * }<br>
064: * <br>
065: * <b>catcher.kill();</b><br>
066: * <br>
067: * String reply = catcher.getServiceReply();<br>
068: * if (reply != null) {<br>
069: * System.out.println("OK");<br>
070: * } else {<br>
071: * System.out.println("ERROR");<br>
072: * }<br>
073: * <br>
074: * Exception e = catcher.getException();<br>
075: * if (e != null) {<br>
076: * e.printStackTrace();<br>
077: * }<br>
078: * </code>
079: * <p>
080: * The <code>kill()</code> method must be called always on the "catcher".
081: * This method does nothing if the "catcher" was able to get the <b>full</b>
082: * reply on time. If the "catcher" was not able to get the full reply because
083: * it was killed, the returned reply is <code>null</code>.<p>
084: *
085: * This thread is managed by {@link ServiceReplyCatcher}.
086: *
087: * @author Daniel Fernandez
088: * @since 1.0
089: */
090: public class ServiceReplyCatcherThread extends Thread {
091:
092: /** The URL to get the reply from */
093: private URL url = null;
094:
095: /** The full reply */
096: private String reply = null;
097:
098: /** The exception got by the thread if any */
099: private Exception exception = null;
100:
101: /** Indicates if the <code>kill()</code> method was called */
102: private boolean killed = false;
103:
104: /** The input stream to read the reply */
105: private InputStream inputStream = null;
106:
107: /**
108: * Constructs an instance of this class.
109: *
110: * @param url the URL to get the reply from
111: */
112: public ServiceReplyCatcherThread(URL url) {
113: this .url = url;
114: }
115:
116: /**
117: * Gets a reply from the URL passed in the constructor. This method is
118: * cancelled if the <code>kill()</code> method is called.
119: */
120: public void run() {
121: try {
122: inputStream = url.openStream();
123:
124: InputStreamReader reader = new InputStreamReader(
125: inputStream);
126: BufferedReader bufferedReader = new BufferedReader(reader);
127:
128: try {
129: String line = null;
130: StringBuffer buffer = new StringBuffer();
131:
132: while ((line = bufferedReader.readLine()) != null
133: && !killed) {
134: buffer.append(line);
135: }
136:
137: if (!killed) {
138: reply = buffer.toString();
139: }
140:
141: } finally {
142: bufferedReader.close();
143: reader.close();
144: inputStream.close();
145: }
146:
147: } catch (Exception exception) {
148: this .exception = exception;
149: }
150:
151: }
152:
153: /**
154: * Gets the exception occured during the catcher operation if any.
155: *
156: * @return the exception or <code>null</code> if no exception occured
157: */
158: public Exception getException() {
159: return exception;
160: }
161:
162: /**
163: * Gets the service reply.
164: *
165: * @return the service reply or <code>null</code> if it was not able to
166: * get the <b>full</b> service reply
167: */
168: public String getServiceReply() {
169: return reply;
170: }
171:
172: /**
173: * Forces exiting from the <code>run()</code> method. The reason of this
174: * method is the deprecation of the <code>stop()</code> method.
175: *
176: * @throws IOException if it was unable to kill the thread
177: */
178: public void kill() throws IOException {
179:
180: killed = true;
181:
182: if (inputStream != null) {
183: /* This interrupts a readLine call in run() */
184: inputStream.close();
185: }
186: }
187:
188: }
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