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1 package org.apache.ojb.broker.locking;
2
3
17
18
19 import javax.servlet.ServletException  ;
20 import javax.servlet.ServletConfig ;
21 import javax.servlet.http.HttpServlet ;
22 import javax.servlet.http.HttpServletRequest ;
23 import javax.servlet.http.HttpServletResponse ;
24 import java.io.IOException ;
25 import java.io.InputStream ;
26 import java.io.ObjectInputStream ;
27 import java.io.ObjectOutputStream ;
28 import java.io.PrintWriter ;
29
30 import org.apache.commons.lang.math.NumberUtils;
31 import org.apache.ojb.broker.util.ClassHelper;
32
33
34
37 public class LockManagerServlet extends HttpServlet
38 {
39 protected static LockManager lockmanager;
40 static final String STR_LOCK_TIMEOUT = "lockTimeout";
41 static final String STR_BLOCK_TIMEOUT = "blockTimeout";
42 static final String STR_LOCK_MANAGER = "lockManager";
43
44 private static long numRequests;
45 private static Throwable lastError = null;
46
47 public void init(ServletConfig servletConfig) throws ServletException
48 {
49 super.init(servletConfig);
50 if(lockmanager == null)
52 {
53 lastError = null;
54 numRequests = 0;
55 String strLockManager = servletConfig.getInitParameter(STR_LOCK_MANAGER);
56 try
57 {
58 lockmanager = (LockManager) (strLockManager != null ?
59 ClassHelper.newInstance(strLockManager) : ClassHelper.newInstance(LockManagerInMemoryImpl.class));
60 }
61 catch(Exception e)
62 {
63 lastError = new LockRuntimeException("Can't instance lock manager, init parameter 'lockManager': " + strLockManager);
64 e.printStackTrace();
65 }
66 String strTimeout = servletConfig.getInitParameter(STR_LOCK_TIMEOUT);
67 if(NumberUtils.isNumber(strTimeout))
68 {
69 try
70 {
71 Long lockTimeout = NumberUtils.createLong(strTimeout);
72 lockmanager.setLockTimeout(lockTimeout.longValue());
73 }
74 catch(Exception e)
75 {
76 if(lastError == null)
77 {
78 lastError = new LockRuntimeException("Can't convert 'lockTimeout' init parameter: " + strTimeout);
79 }
80 e.printStackTrace();
81 }
82 }
83 String strBlock = servletConfig.getInitParameter(STR_BLOCK_TIMEOUT);
84 if(NumberUtils.isNumber(strBlock))
85 {
86 try
87 {
88 Long blockTimeout = NumberUtils.createLong(strBlock);
89 lockmanager.setLockTimeout(blockTimeout.longValue());
90 }
91 catch(Exception e)
92 {
93 if(lastError == null)
94 {
95 lastError = new LockRuntimeException("Can't convert 'blockTimeout' init parameter: " + strBlock);
96 }
97 e.printStackTrace();
98 }
99 }
100 }
101 }
102
103
106 protected void doGet(HttpServletRequest request, HttpServletResponse response)
107 throws ServletException , IOException
108 {
109 response.setContentType("text/html");
110 response.setHeader("Pragma", "no-cache");
111
112 PrintWriter out = response.getWriter();
113
114 out.println("<html><head><title>OJB Distributed Locking Servlet Status Page</title>");
115 out.println("</head><body><h1>OJB Distributed Locking Servlet</h1>");
116 out.println("The servlet is running.<p>");
117
118 if(lastError == null)
119 {
120 out.println("The LockServer is running.<p>");
121 out.println("LockManager info: " + lockmanager.getLockInfo() + "<p>");
122 out.println("Processed Lock Request: " + numRequests + "<p>");
123 }
124 else
125 {
126 out.println("<h2>The LockServer has a problem!</h2>");
127 out.println("The error message is:<p>");
128 out.println(lastError.getMessage() + "<p>");
129 lastError.printStackTrace(out);
130 lastError = null;
131 }
132
133 out.println("</body></html>");
134 }
135
136
139 protected void doPost(HttpServletRequest request, HttpServletResponse response)
140 throws ServletException , IOException
141 {
142 numRequests++;
144
145 try
146 {
147 LockManagerRemoteImpl.LockInfo info = (LockManagerRemoteImpl.LockInfo) buildObjectFromRequest(request);
149 Object result = null;
150 try
152 {
153 switch(info.methodName)
154 {
155 case LockManagerRemoteImpl.METHOD_READ_LOCK:
156 {
157 result = new Boolean (lockmanager.readLock(info.key, info.resourceId, info.isolationLevel));
158 break;
159 }
160 case LockManagerRemoteImpl.METHOD_RELEASE_SINGLE_LOCK:
161 {
162 result = new Boolean (lockmanager.releaseLock(info.key, info.resourceId));
163 break;
164 }
165 case LockManagerRemoteImpl.METHOD_RELEASE_LOCKS:
166 {
167 lockmanager.releaseLocks(info.key);
168 result = Boolean.TRUE;
169 break;
170 }
171 case LockManagerRemoteImpl.METHOD_WRITE_LOCK:
172 {
173 result = new Boolean (lockmanager.writeLock(info.key, info.resourceId,
174 info.isolationLevel));
175 break;
176 }
177 case LockManagerRemoteImpl.METHOD_UPGRADE_LOCK:
178 {
179 result = new Boolean (lockmanager.upgradeLock(info.key, info.resourceId, info.isolationLevel));
180 break;
181 }
182 case LockManagerRemoteImpl.METHOD_CHECK_READ:
183 {
184 result = new Boolean (lockmanager.hasRead(info.key, info.resourceId));
185 break;
186 }
187 case LockManagerRemoteImpl.METHOD_CHECK_WRITE:
188 {
189 result = new Boolean (lockmanager.hasWrite(info.key, info.resourceId));
190 break;
191 }
192 case LockManagerRemoteImpl.METHOD_CHECK_UPGRADE:
193 {
194 result = new Boolean (lockmanager.hasUpgrade(info.key, info.resourceId));
195 break;
196 }
197 case LockManagerRemoteImpl.METHOD_LOCK_INFO:
198 {
199 result = lockmanager.getLockInfo();
200 break;
201 }
202 case LockManagerRemoteImpl.METHOD_LOCK_TIMEOUT:
203 {
204 result = new Long (lockmanager.getLockTimeout());
205 break;
206 }
207 case LockManagerRemoteImpl.METHOD_BLOCK_TIMEOUT:
208 {
209 result = new Long (lockmanager.getBlockTimeout());
210 break;
211 }
212 default :
224 {
225 throw new LockRuntimeException("Unknown command:" + info.methodName);
226 }
227 }
228 }
229 catch(RuntimeException e)
230 {
231 result = new LockRuntimeException("Error while invoke specified method in servlet.", e);
232 }
233
234 ObjectOutputStream oos = new ObjectOutputStream (response.getOutputStream());
235 oos.writeObject(result);
236 oos.flush();
237 oos.close();
238 }
239 catch(Throwable t)
240 {
241 lastError = t;
242 t.printStackTrace();
243 }
244 }
245
246 private Object buildObjectFromRequest(HttpServletRequest request) throws IOException , ClassNotFoundException
247 {
248 Object obj = null;
249 InputStream is = request.getInputStream();
251 ObjectInputStream objInputStream = new ObjectInputStream (is);
252 obj = objInputStream.readObject();
253 objInputStream.close();
254 is.close();
255 return obj;
256 }
257 }
258 |
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