1 /*
2 * Copyright (c) 2016, 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 jdk.jshell.execution;
26
27 import java.io.IOException;
28 import java.io.ObjectInput;
29 import java.io.ObjectOutput;
30 import jdk.jshell.JShellException;
31 import jdk.jshell.spi.ExecutionControl;
32 import static jdk.jshell.execution.RemoteCodes.*;
33
34 /**
35 * An implementation of the {@link jdk.jshell.spi.ExecutionControl}
36 * execution engine SPI which streams requests to a remote agent where
37 * execution takes place.
38 *
39 * @author Robert Field
40 */
41 public class StreamingExecutionControl implements ExecutionControl {
42
43 private final ObjectOutput out;
44 private final ObjectInput in;
45
46 /**
47 * Creates an instance.
48 *
49 * @param out the output for commands
50 * @param in the input for command responses
51 */
52 public StreamingExecutionControl(ObjectOutput out, ObjectInput in) {
53 this.out = out;
54 this.in = in;
55 }
56
57 @Override
58 public void load(ClassBytecodes[] cbcs)
59 throws ClassInstallException, NotImplementedException, EngineTerminationException {
60 try {
61 // Send a load command to the remote agent.
62 writeCommand(CMD_LOAD);
63 out.writeObject(cbcs);
64 out.flush();
65 // Retrieve and report results from the remote agent.
66 readAndReportClassInstallResult();
67 } catch (IOException ex) {
68 throw new EngineTerminationException("Exception writing remote load: " + ex);
69 }
70 }
71
72 @Override
73 public void redefine(ClassBytecodes[] cbcs)
74 throws ClassInstallException, NotImplementedException, EngineTerminationException {
75 try {
76 // Send a load command to the remote agent.
77 writeCommand(CMD_REDEFINE);
78 out.writeObject(cbcs);
79 out.flush();
80 // Retrieve and report results from the remote agent.
81 readAndReportClassInstallResult();
82 } catch (IOException ex) {
83 throw new EngineTerminationException("Exception writing remote redefine: " + ex);
84 }
85 }
86
87 @Override
88 public String invoke(String classname, String methodname)
89 throws RunException, EngineTerminationException, InternalException {
90 try {
91 // Send the invoke command to the remote agent.
92 writeCommand(CMD_INVOKE);
93 out.writeUTF(classname);
94 out.writeUTF(methodname);
95 out.flush();
96 // Retrieve and report results from the remote agent.
97 readAndReportExecutionResult();
98 String result = in.readUTF();
99 return result;
100 } catch (IOException ex) {
101 throw new EngineTerminationException("Exception writing remote invoke: " + ex);
102 }
103 }
104
105 @Override
106 public String varValue(String classname, String varname)
107 throws RunException, EngineTerminationException, InternalException {
108 try {
109 // Send the variable-value command to the remote agent.
110 writeCommand(CMD_VAR_VALUE);
111 out.writeUTF(classname);
112 out.writeUTF(varname);
113 out.flush();
114 // Retrieve and report results from the remote agent.
115 readAndReportExecutionResult();
116 String result = in.readUTF();
117 return result;
118 } catch (IOException ex) {
119 throw new EngineTerminationException("Exception writing remote varValue: " + ex);
120 }
121 }
122
123
124 @Override
125 public void addToClasspath(String path)
126 throws EngineTerminationException, InternalException {
127 try {
128 // Send the classpath addition command to the remote agent.
129 writeCommand(CMD_ADD_CLASSPATH);
130 out.writeUTF(path);
131 out.flush();
132 // Retrieve and report results from the remote agent.
133 readAndReportClassSimpleResult();
134 } catch (IOException ex) {
135 throw new EngineTerminationException("Exception writing remote add to classpath: " + ex);
136 }
137 }
138
139 @Override
140 public void setClasspath(String path)
141 throws EngineTerminationException, InternalException {
142 try {
143 // Send the classpath addition command to the remote agent.
144 writeCommand(CMD_SET_CLASSPATH);
145 out.writeUTF(path);
146 out.flush();
147 // Retrieve and report results from the remote agent.
148 readAndReportClassSimpleResult();
149 } catch (IOException ex) {
150 throw new EngineTerminationException("Exception writing remote set classpath: " + ex);
151 }
152 }
153
154 @Override
155 public void stop()
156 throws EngineTerminationException, InternalException {
157 try {
158 // Send the variable-value command to the remote agent.
159 writeCommand(CMD_STOP);
160 out.flush();
161 } catch (IOException ex) {
162 throw new EngineTerminationException("Exception writing remote stop: " + ex);
163 }
164 }
165
166 @Override
167 public Object extensionCommand(String command, Object arg)
168 throws RunException, EngineTerminationException, InternalException {
169 try {
170 writeCommand(command);
171 out.writeObject(arg);
172 out.flush();
173 // Retrieve and report results from the remote agent.
174 readAndReportExecutionResult();
175 Object result = in.readObject();
176 return result;
177 } catch (IOException | ClassNotFoundException ex) {
178 throw new EngineTerminationException("Exception transmitting remote extensionCommand: "
179 + command + " -- " + ex);
180 }
181 }
182
183 /**
184 * Closes the execution engine. Send an exit command to the remote agent.
185 */
186 @Override
187 public void close() {
188 try {
189 writeCommand(CMD_CLOSE);
190 out.flush();
191 } catch (IOException ex) {
192 // ignore;
193 }
194 }
195
196 private void writeCommand(String cmd) throws IOException {
197 out.writeInt(COMMAND_PREFIX);
198 out.writeUTF(cmd);
199 }
200
201 /**
202 * Reports results from a remote agent command that does not expect
203 * exceptions.
204 */
205 private void readAndReportClassSimpleResult() throws EngineTerminationException, InternalException {
206 try {
207 int status = in.readInt();
208 switch (status) {
209 case RESULT_SUCCESS:
210 return;
211 case RESULT_NOT_IMPLEMENTED: {
212 String message = in.readUTF();
213 throw new NotImplementedException(message);
214 }
215 case RESULT_INTERNAL_PROBLEM: {
216 String message = in.readUTF();
217 throw new InternalException(message);
218 }
219 case RESULT_TERMINATED: {
220 String message = in.readUTF();
221 throw new EngineTerminationException(message);
222 }
223 default: {
224 throw new EngineTerminationException("Bad remote result code: " + status);
225 }
226 }
227 } catch (IOException ex) {
228 throw new EngineTerminationException(ex.toString());
229 }
230 }
231
232 /**
233 * Reports results from a remote agent command that does not expect
234 * exceptions.
235 */
236 private void readAndReportClassInstallResult() throws ClassInstallException,
237 NotImplementedException, EngineTerminationException {
238 try {
239 int status = in.readInt();
240 switch (status) {
241 case RESULT_SUCCESS:
242 return;
243 case RESULT_NOT_IMPLEMENTED: {
244 String message = in.readUTF();
245 throw new NotImplementedException(message);
246 }
247 case RESULT_CLASS_INSTALL_EXCEPTION: {
248 String message = in.readUTF();
249 boolean[] loaded = (boolean[]) in.readObject();
250 throw new ClassInstallException(message, loaded);
251 }
252 case RESULT_TERMINATED: {
253 String message = in.readUTF();
254 throw new EngineTerminationException(message);
255 }
256 default: {
257 throw new EngineTerminationException("Bad remote result code: " + status);
258 }
259 }
260 } catch (IOException | ClassNotFoundException ex) {
261 throw new EngineTerminationException(ex.toString());
262 }
263 }
264
265 /**
266 * Reports results from a remote agent command that expects runtime
267 * exceptions.
268 *
269 * @return true if successful
270 * @throws IOException if the connection has dropped
271 * @throws JShellException {@link jdk.jshell.EvalException}, if a user
272 * exception was encountered on invoke;
273 * {@link jdk.jshell.UnresolvedReferenceException}, if an unresolved
274 * reference was encountered
275 * @throws java.lang.ClassNotFoundException
276 */
277 private void readAndReportExecutionResult() throws RunException,
278 EngineTerminationException, InternalException {
279 try {
280 int status = in.readInt();
281 switch (status) {
282 case RESULT_SUCCESS:
283 return;
284 case RESULT_NOT_IMPLEMENTED: {
285 String message = in.readUTF();
286 throw new NotImplementedException(message);
287 }
288 case RESULT_USER_EXCEPTION: {
289 // A user exception was encountered.
290 String message = in.readUTF();
291 String exceptionClassName = in.readUTF();
292 StackTraceElement[] elems = (StackTraceElement[]) in.readObject();
293 throw new UserException(message, exceptionClassName, elems);
294 }
295 case RESULT_CORRALLED: {
296 // An unresolved reference was encountered.
297 int id = in.readInt();
298 StackTraceElement[] elems = (StackTraceElement[]) in.readObject();
299 ResolutionException re = new ResolutionException(id, elems);
300 throw re;
301 }
302 case RESULT_STOPPED: {
303 // Execution was aborted by the stop()
304 throw new StoppedException();
305 }
306 case RESULT_INTERNAL_PROBLEM: {
307 // An internal error has occurred.
308 String message = in.readUTF();
309 throw new InternalException(message);
310 }
311 case RESULT_TERMINATED: {
312 String message = in.readUTF();
313 throw new EngineTerminationException(message);
314 }
315 default: {
316 throw new EngineTerminationException("Bad remote result code: " + status);
317 }
318 }
319 } catch (IOException | ClassNotFoundException ex) {
320 throw new EngineTerminationException(ex.toString());
321 }
322 }
323
324 }