rse/plugins/org.eclipse.dltk.rse.ui/src/org/eclipse/dltk/internal/ui/rse/RSEConnector.java

package org.eclipse.dltk.internal.ui.rse;

import java.util.HashSet;
import java.util.Set;

import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.OperationCanceledException;
import org.eclipse.dltk.core.internal.rse.DLTKRSEPlugin;
import org.eclipse.dltk.core.internal.rse.RSEConnectionQueryManager;
import org.eclipse.dltk.core.internal.rse.RSEConnectionQueryManager.IConnector;
import org.eclipse.rse.core.model.IHost;
import org.eclipse.rse.core.subsystems.ISubSystem;
import org.eclipse.rse.subsystems.files.core.subsystems.IRemoteFileSubSystem;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.PlatformUI;

/**
 * @since 2.0
 */
public class RSEConnector implements IConnector {
	private static boolean running = true;
	private Thread processingThread = null;

	private Thread createProcessingThread() {
		return new Thread("RSE connection resolver") {
			@Override
			public void run() {
				while (running) {
					if (RSEConnectionQueryManager.getInstance().hasHosts()) {
						Display display = PlatformUI.getWorkbench()
								.getDisplay();
						if (PlatformUI.getWorkbench().isClosing()) {
							IHost host = RSEConnectionQueryManager
									.getInstance().getNextHost(false);
							if (host != null) {
								RSEConnectionQueryManager.getInstance()
										.markHostAsFinished(host);
							}
						} else {
							display.syncExec(() -> {
								IHost host = RSEConnectionQueryManager
										.getInstance().getNextHost(false);
								if (host != null) {
									connect(host);
									RSEConnectionQueryManager.getInstance()
											.markHostAsFinished(host);
								}
							});
						}
					}
					try {
						Thread.sleep(200);
					} catch (InterruptedException e) {
						DLTKRSEPlugin.log(e);
					}
				}
			}
		};
	}

	private final Set<IHost> activeConnects = new HashSet<>();

	private void connect(IHost host) {
		ISubSystem[] subSystems = host.getSubSystems();
		for (ISubSystem subsystem : subSystems) {
			if (subsystem instanceof IRemoteFileSubSystem) {
				try {
					synchronized (activeConnects) {
						if (!activeConnects.add(host))
							return;
					}
					try {
						subsystem.connect(new NullProgressMonitor(), false);
					} finally {
						synchronized (activeConnects) {
							activeConnects.remove(host);
						}
					}
				} catch (OperationCanceledException e) {
					// don't log it
				} catch (Exception e) {
					DLTKRSEPlugin.log(e);
				}
			}
		}
	};

	public RSEConnector() {
	}

	@Override
	public boolean isDirectProcessingRequired() {
		// Process direct connection request.
		Display current = Display.getCurrent();
		if (current != null) {
			// We are in UI thread
			return true;
		}
		return false;
	}

	@Override
	public void register() {
		if (processingThread == null) {
			processingThread = createProcessingThread();
			processingThread.start();
		}
	}

	@Override
	public void runDisplayRunnables(long timeout) {
		long end = System.currentTimeMillis() + timeout;
		// We need to interrupt processingThread if it is no executing.
		Display current = Display.getCurrent();
		MAIN_LOOP: while (RSEConnectionQueryManager.getInstance().hasHosts()
				&& !current.isDisposed()
				&& !PlatformUI.getWorkbench().isClosing()) {
			while (current.readAndDispatch()) {
				if (current.isDisposed()) {
					break MAIN_LOOP;
				}
			}
			if (end < System.currentTimeMillis()) { // Timeout
				break;
			}
			IHost host = RSEConnectionQueryManager.getInstance().getNextHost(
					false);
			if (host != null) {
				connect(host);
				RSEConnectionQueryManager.getInstance()
						.markHostAsFinished(host);
			}
		}
	}

	public static void stop() {
		running = false;
	}
}