| /* |
| * Copyright (c) 1998, 2014, 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.util.function.Consumer; |
| import com.sun.jdi.*; |
| import com.sun.jdi.event.*; |
| |
| /** |
| * Handler of Java Debug Interface events. |
| * Adapted from jdb EventHandler. |
| * Only exit and disconnect events processed. |
| */ |
| class JdiEventHandler implements Runnable { |
| |
| private final Thread thread; |
| private volatile boolean connected = true; |
| private boolean completed = false; |
| private final VirtualMachine vm; |
| private final Consumer<String> reportVMExit; |
| |
| /** |
| * Creates an event handler. Start with {@code start()}. |
| * |
| * @param vm the virtual machine for which to handle events |
| * @param reportVMExit callback to report exit/disconnect |
| * (passed true if the VM has died) |
| */ |
| JdiEventHandler(VirtualMachine vm, Consumer<String> reportVMExit) { |
| this.vm = vm; |
| this.reportVMExit = reportVMExit; |
| this.thread = new Thread(this, "event-handler"); |
| this.thread.setDaemon(true); |
| } |
| |
| /** |
| * Starts the event handler. |
| */ |
| void start() { |
| thread.start(); |
| } |
| |
| synchronized void shutdown() { |
| connected = false; // force run() loop termination |
| thread.interrupt(); |
| while (!completed) { |
| try {wait();} catch (InterruptedException exc) {} |
| } |
| } |
| |
| @Override |
| public void run() { |
| EventQueue queue = vm.eventQueue(); |
| while (connected) { |
| try { |
| EventSet eventSet = queue.remove(); |
| boolean resumeStoppedApp = false; |
| EventIterator it = eventSet.eventIterator(); |
| while (it.hasNext()) { |
| resumeStoppedApp |= handleEvent(it.nextEvent()); |
| } |
| |
| if (resumeStoppedApp) { |
| eventSet.resume(); |
| } |
| } catch (InterruptedException exc) { |
| // Do nothing. Any changes will be seen at top of loop. |
| } catch (VMDisconnectedException discExc) { |
| handleDisconnectedException(); |
| break; |
| } |
| } |
| synchronized (this) { |
| completed = true; |
| notifyAll(); |
| } |
| } |
| |
| private boolean handleEvent(Event event) { |
| handleExitEvent(event); |
| return true; |
| } |
| |
| private void handleExitEvent(Event event) { |
| if (event instanceof VMDeathEvent) { |
| reportVMExit.accept("VM Died"); |
| } else if (event instanceof VMDisconnectEvent) { |
| connected = false; |
| reportVMExit.accept("VM Disconnected"); |
| } else { |
| // ignore everything else |
| } |
| } |
| |
| private synchronized void handleDisconnectedException() { |
| /* |
| * A VMDisconnectedException has happened while dealing with |
| * another event. We need to flush the event queue, dealing only |
| * with exit events (VMDeath, VMDisconnect) so that we terminate |
| * correctly. |
| */ |
| EventQueue queue = vm.eventQueue(); |
| while (connected) { |
| try { |
| EventSet eventSet = queue.remove(); |
| EventIterator iter = eventSet.eventIterator(); |
| while (iter.hasNext()) { |
| handleExitEvent(iter.next()); |
| } |
| } catch (InterruptedException exc) { |
| // ignore |
| } catch (InternalError exc) { |
| // ignore |
| } |
| } |
| } |
| } |