langtools/src/jdk.jshell/share/classes/jdk/jshell/execution/StreamingExecutionControl.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/src/jdk.jshell/share/classes/jdk/jshell/execution/StreamingExecutionControl.java Wed Jul 20 23:19:09 2016 -0700
@@ -0,0 +1,324 @@
+/*
+ * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package jdk.jshell.execution;
+
+import java.io.IOException;
+import java.io.ObjectInput;
+import java.io.ObjectOutput;
+import jdk.jshell.JShellException;
+import jdk.jshell.spi.ExecutionControl;
+import static jdk.jshell.execution.RemoteCodes.*;
+
+/**
+ * An implementation of the {@link jdk.jshell.spi.ExecutionControl}
+ * execution engine SPI which streams requests to a remote agent where
+ * execution takes place.
+ *
+ * @author Robert Field
+ */
+public class StreamingExecutionControl implements ExecutionControl {
+
+ private final ObjectOutput out;
+ private final ObjectInput in;
+
+ /**
+ * Creates an instance.
+ *
+ * @param out the output for commands
+ * @param in the input for command responses
+ */
+ public StreamingExecutionControl(ObjectOutput out, ObjectInput in) {
+ this.out = out;
+ this.in = in;
+ }
+
+ @Override
+ public void load(ClassBytecodes[] cbcs)
+ throws ClassInstallException, NotImplementedException, EngineTerminationException {
+ try {
+ // Send a load command to the remote agent.
+ writeCommand(CMD_LOAD);
+ out.writeObject(cbcs);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportClassInstallResult();
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote load: " + ex);
+ }
+ }
+
+ @Override
+ public void redefine(ClassBytecodes[] cbcs)
+ throws ClassInstallException, NotImplementedException, EngineTerminationException {
+ try {
+ // Send a load command to the remote agent.
+ writeCommand(CMD_REDEFINE);
+ out.writeObject(cbcs);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportClassInstallResult();
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote redefine: " + ex);
+ }
+ }
+
+ @Override
+ public String invoke(String classname, String methodname)
+ throws RunException, EngineTerminationException, InternalException {
+ try {
+ // Send the invoke command to the remote agent.
+ writeCommand(CMD_INVOKE);
+ out.writeUTF(classname);
+ out.writeUTF(methodname);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportExecutionResult();
+ String result = in.readUTF();
+ return result;
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote invoke: " + ex);
+ }
+ }
+
+ @Override
+ public String varValue(String classname, String varname)
+ throws RunException, EngineTerminationException, InternalException {
+ try {
+ // Send the variable-value command to the remote agent.
+ writeCommand(CMD_VAR_VALUE);
+ out.writeUTF(classname);
+ out.writeUTF(varname);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportExecutionResult();
+ String result = in.readUTF();
+ return result;
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote varValue: " + ex);
+ }
+ }
+
+
+ @Override
+ public void addToClasspath(String path)
+ throws EngineTerminationException, InternalException {
+ try {
+ // Send the classpath addition command to the remote agent.
+ writeCommand(CMD_ADD_CLASSPATH);
+ out.writeUTF(path);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportClassSimpleResult();
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote add to classpath: " + ex);
+ }
+ }
+
+ @Override
+ public void setClasspath(String path)
+ throws EngineTerminationException, InternalException {
+ try {
+ // Send the classpath addition command to the remote agent.
+ writeCommand(CMD_SET_CLASSPATH);
+ out.writeUTF(path);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportClassSimpleResult();
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote set classpath: " + ex);
+ }
+ }
+
+ @Override
+ public void stop()
+ throws EngineTerminationException, InternalException {
+ try {
+ // Send the variable-value command to the remote agent.
+ writeCommand(CMD_STOP);
+ out.flush();
+ } catch (IOException ex) {
+ throw new EngineTerminationException("Exception writing remote stop: " + ex);
+ }
+ }
+
+ @Override
+ public Object extensionCommand(String command, Object arg)
+ throws RunException, EngineTerminationException, InternalException {
+ try {
+ writeCommand(command);
+ out.writeObject(arg);
+ out.flush();
+ // Retrieve and report results from the remote agent.
+ readAndReportExecutionResult();
+ Object result = in.readObject();
+ return result;
+ } catch (IOException | ClassNotFoundException ex) {
+ throw new EngineTerminationException("Exception transmitting remote extensionCommand: "
+ + command + " -- " + ex);
+ }
+ }
+
+ /**
+ * Closes the execution engine. Send an exit command to the remote agent.
+ */
+ @Override
+ public void close() {
+ try {
+ writeCommand(CMD_CLOSE);
+ out.flush();
+ } catch (IOException ex) {
+ // ignore;
+ }
+ }
+
+ private void writeCommand(String cmd) throws IOException {
+ out.writeInt(COMMAND_PREFIX);
+ out.writeUTF(cmd);
+ }
+
+ /**
+ * Reports results from a remote agent command that does not expect
+ * exceptions.
+ */
+ private void readAndReportClassSimpleResult() throws EngineTerminationException, InternalException {
+ try {
+ int status = in.readInt();
+ switch (status) {
+ case RESULT_SUCCESS:
+ return;
+ case RESULT_NOT_IMPLEMENTED: {
+ String message = in.readUTF();
+ throw new NotImplementedException(message);
+ }
+ case RESULT_INTERNAL_PROBLEM: {
+ String message = in.readUTF();
+ throw new InternalException(message);
+ }
+ case RESULT_TERMINATED: {
+ String message = in.readUTF();
+ throw new EngineTerminationException(message);
+ }
+ default: {
+ throw new EngineTerminationException("Bad remote result code: " + status);
+ }
+ }
+ } catch (IOException ex) {
+ throw new EngineTerminationException(ex.toString());
+ }
+ }
+
+ /**
+ * Reports results from a remote agent command that does not expect
+ * exceptions.
+ */
+ private void readAndReportClassInstallResult() throws ClassInstallException,
+ NotImplementedException, EngineTerminationException {
+ try {
+ int status = in.readInt();
+ switch (status) {
+ case RESULT_SUCCESS:
+ return;
+ case RESULT_NOT_IMPLEMENTED: {
+ String message = in.readUTF();
+ throw new NotImplementedException(message);
+ }
+ case RESULT_CLASS_INSTALL_EXCEPTION: {
+ String message = in.readUTF();
+ boolean[] loaded = (boolean[]) in.readObject();
+ throw new ClassInstallException(message, loaded);
+ }
+ case RESULT_TERMINATED: {
+ String message = in.readUTF();
+ throw new EngineTerminationException(message);
+ }
+ default: {
+ throw new EngineTerminationException("Bad remote result code: " + status);
+ }
+ }
+ } catch (IOException | ClassNotFoundException ex) {
+ throw new EngineTerminationException(ex.toString());
+ }
+ }
+
+ /**
+ * Reports results from a remote agent command that expects runtime
+ * exceptions.
+ *
+ * @return true if successful
+ * @throws IOException if the connection has dropped
+ * @throws JShellException {@link jdk.jshell.EvalException}, if a user
+ * exception was encountered on invoke;
+ * {@link jdk.jshell.UnresolvedReferenceException}, if an unresolved
+ * reference was encountered
+ * @throws java.lang.ClassNotFoundException
+ */
+ private void readAndReportExecutionResult() throws RunException,
+ EngineTerminationException, InternalException {
+ try {
+ int status = in.readInt();
+ switch (status) {
+ case RESULT_SUCCESS:
+ return;
+ case RESULT_NOT_IMPLEMENTED: {
+ String message = in.readUTF();
+ throw new NotImplementedException(message);
+ }
+ case RESULT_USER_EXCEPTION: {
+ // A user exception was encountered.
+ String message = in.readUTF();
+ String exceptionClassName = in.readUTF();
+ StackTraceElement[] elems = (StackTraceElement[]) in.readObject();
+ throw new UserException(message, exceptionClassName, elems);
+ }
+ case RESULT_CORRALLED: {
+ // An unresolved reference was encountered.
+ int id = in.readInt();
+ StackTraceElement[] elems = (StackTraceElement[]) in.readObject();
+ ResolutionException re = new ResolutionException(id, elems);
+ throw re;
+ }
+ case RESULT_STOPPED: {
+ // Execution was aborted by the stop()
+ throw new StoppedException();
+ }
+ case RESULT_INTERNAL_PROBLEM: {
+ // An internal error has occurred.
+ String message = in.readUTF();
+ throw new InternalException(message);
+ }
+ case RESULT_TERMINATED: {
+ String message = in.readUTF();
+ throw new EngineTerminationException(message);
+ }
+ default: {
+ throw new EngineTerminationException("Bad remote result code: " + status);
+ }
+ }
+ } catch (IOException | ClassNotFoundException ex) {
+ throw new EngineTerminationException(ex.toString());
+ }
+ }
+
+}