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1
56 package org.objectstyle.cayenne.distribution;
57
58 import org.objectstyle.cayenne.client.CayenneClientException;
59 import org.objectstyle.cayenne.util.Util;
60
61 import com.caucho.hessian.client.HessianProxyFactory;
62 import com.caucho.hessian.client.HessianRuntimeException;
63 import com.caucho.hessian.io.HessianProtocolException;
64
65
73 public class HessianConnector implements CayenneConnector {
74
75 protected String  url;
76 protected String userName;
77 protected String password;
78 protected String sessionId;
79
80 protected HessianService service;
81
82 public HessianConnector(String url, String userName, String password) {
83 this.url = url;
84 this.userName = userName;
85 this.password = password;
86 }
87
88
91 public void connect() throws CayenneClientException {
92 try {
94 this.service = (HessianService) new HessianProxyFactory()
95 .create(HessianService.class, url);
96 }
97 catch (Throwable th) {
98 th = unwindThrowable(th);
99 String message = buildExceptionMessage("URL error", th);
100 throw new CayenneClientException(message, th);
101 }
102
103 try {
105 this.sessionId = service.establishSession(userName, password);
106 }
107 catch (Throwable th) {
108 th = unwindThrowable(th);
109 String message = buildExceptionMessage("Error establishing remote session",
110 th);
111 throw new CayenneClientException(message, th);
112 }
113 }
114
115 public Object sendMessage(ClientMessage message) throws CayenneClientException {
116 if (sessionId == null) {
118 throw new CayenneClientException("Not connected, can't call 'invokeRemote'.");
119 }
120
121 try {
122 return service.processMessage(sessionId, message);
123 }
124 catch (Throwable th) {
125 th = unwindThrowable(th);
126 String errorMessage = buildExceptionMessage("Remote error", th);
127 throw new CayenneClientException(errorMessage, th);
128 }
129 }
130
131 protected String buildExceptionMessage(String message, Throwable th) {
132
133 StringBuffer buffer = new StringBuffer (message);
134 buffer.append(". URL - ").append(url);
135
136 String thMessage = th.getMessage();
137 if (!Util.isEmptyString(thMessage)) {
138 buffer.append("; CAUSE - ").append(thMessage);
139 }
140
141 return buffer.toString();
142 }
143
144
148 protected Throwable unwindThrowable(Throwable th) {
149 if (th instanceof HessianProtocolException) {
150 Throwable cause = ((HessianProtocolException) th).getRootCause();
151
152 if (cause != null) {
153 return unwindThrowable(cause);
154 }
155 }
156 else if (th instanceof HessianRuntimeException) {
157 Throwable cause = ((HessianRuntimeException) th).getRootCause();
158
159 if (cause != null) {
160 return unwindThrowable(cause);
161 }
162 }
163
164 return Util.unwindException(th);
165 }
166 } |
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