Java tutorial
/******************************************************************************* * Copyright (c) 2004, 2015 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * IBM Corporation - initial API and implementation * Chris Gross (schtoo@schtoo.com) - support for ILogger added * (bug 49497 [RCP] JFace dependency on org.eclipse.core.runtime enlarges standalone JFace applications) *******************************************************************************/ package org.eclipse.jface.util; import java.util.Comparator; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.Status; import org.eclipse.jface.dialogs.AnimatorFactory; import org.eclipse.jface.dialogs.ErrorSupportProvider; import org.eclipse.swt.widgets.Display; /** * The Policy class handles settings for behaviour, debug flags and logging * within JFace. * * @since 3.0 */ public class Policy { /** * Constant for the the default setting for debug options. */ public static final boolean DEFAULT = false; /** * The unique identifier of the JFace plug-in. */ public static final String JFACE = "org.eclipse.jface"; //$NON-NLS-1$ private static ILogger log; /** * The comparator used by JFace to sort strings, or {@code null}. * <p> * Note: The type is {@code Comparator<Object>} because this is usually a * {@link java.text.Collator} (or its ICU equivalent), and Collator * implements {@code Comparator<Object>}. See * https://bugs.eclipse.org/434325 . * </p> */ private static Comparator<Object> viewerComparator; private static AnimatorFactory animatorFactory; /** * A flag to indicate whether unparented dialogs should be checked. */ public static boolean DEBUG_DIALOG_NO_PARENT = DEFAULT; /** * A flag to indicate whether actions are being traced. */ public static boolean TRACE_ACTIONS = DEFAULT; /** * A flag to indicate whether toolbars are being traced. */ public static boolean TRACE_TOOLBAR = DEFAULT; private static ErrorSupportProvider errorSupportProvider; private static StatusHandler statusHandler; /** * Returns the dummy log to use if none has been set */ private static ILogger getDummyLog() { return status -> { System.err.println(status.getMessage()); if (status.getException() != null) { status.getException().printStackTrace(System.err); } }; } /** * Sets the logger used by JFace to log errors. * * @param logger * the logger to use, or <code>null</code> to use the default * logger * @since 3.1 */ public static void setLog(ILogger logger) { log = logger; } /** * Returns the logger used by JFace to log errors. * <p> * The default logger prints the status to <code>System.err</code>. * </p> * * @return the logger * @since 3.1 */ public static ILogger getLog() { if (log == null) { log = getDummyLog(); } return log; } /** * Sets the status handler used by JFace to handle statuses. * * @param status * the handler to use, or <code>null</code> to use the default * one * @since 3.4 */ public static void setStatusHandler(StatusHandler status) { statusHandler = status; } /** * Returns the status handler used by JFace to handle statuses. * * @return the status handler * @since 3.4 */ public static StatusHandler getStatusHandler() { if (statusHandler == null) { statusHandler = getDummyStatusHandler(); } return statusHandler; } private static StatusHandler getDummyStatusHandler() { return new StatusHandler() { private SafeRunnableDialog dialog; @Override public void show(final IStatus status, String title) { Runnable runnable = () -> { if (dialog == null || dialog.getShell().isDisposed()) { dialog = new SafeRunnableDialog(status); dialog.create(); dialog.getShell().addDisposeListener(e -> dialog = null); dialog.open(); } else { dialog.addStatus(status); dialog.refresh(); } }; if (Display.getCurrent() != null) { runnable.run(); } else { Display.getDefault().asyncExec(runnable); } } }; } /** * Return the default comparator used by JFace to sort strings. * * @return a default comparator used by JFace to sort strings */ private static Comparator<Object> getDefaultComparator() { return (s1, s2) -> ((String) s1).compareTo((String) s2); } /** * Return the comparator used by JFace to sort strings. * * @return the comparator used by JFace to sort strings * @since 3.2 */ public static Comparator<Object> getComparator() { if (viewerComparator == null) { viewerComparator = getDefaultComparator(); } return viewerComparator; } /** * Sets the comparator used by JFace to sort strings. * * @param comparator * comparator used by JFace to sort strings * @since 3.2 */ public static void setComparator(Comparator<Object> comparator) { org.eclipse.core.runtime.Assert.isTrue(viewerComparator == null); viewerComparator = comparator; } /** * Sets the animator factory used by JFace to create control animator * instances. * * @param factory * the AnimatorFactory to use. * @since 3.2 * @deprecated this is no longer in use as of 3.3 */ @Deprecated public static void setAnimatorFactory(AnimatorFactory factory) { animatorFactory = factory; } /** * Returns the animator factory used by JFace to create control animator * instances. * * @return the animator factory used to create control animator instances. * @since 3.2 * @deprecated this is no longer in use as of 3.3 */ @Deprecated public static AnimatorFactory getAnimatorFactory() { if (animatorFactory == null) animatorFactory = new AnimatorFactory(); return animatorFactory; } /** * Set the error support provider for error dialogs. * * @param provider provider to set * @since 3.3 */ public static void setErrorSupportProvider(ErrorSupportProvider provider) { errorSupportProvider = provider; } /** * Return the ErrorSupportProvider for the receiver. * * @return ErrorSupportProvider or <code>null</code> if this has not been * set * @since 3.3 */ public static ErrorSupportProvider getErrorSupportProvider() { return errorSupportProvider; } /** * Log the Exception to the logger. * * @param exception exception to log * @since 3.4 */ public static void logException(Exception exception) { getLog().log(new Status(IStatus.ERROR, JFACE, exception.getLocalizedMessage(), exception)); } }