-/*******************************************************************************\r
- * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
- * in Industry THTH ry.\r
- * All rights reserved. This program and the accompanying materials\r
- * are made available under the terms of the Eclipse Public License v1.0\r
- * which accompanies this distribution, and is available at\r
- * http://www.eclipse.org/legal/epl-v10.html\r
- *\r
- * Contributors:\r
- * VTT Technical Research Centre of Finland - initial API and implementation\r
- *******************************************************************************/\r
-package org.simantics.utils.datastructures.hints;\r
-\r
-/**\r
- * HintTracker is a helper class for tracking any hints of a single\r
- * IHintContext.\r
- * \r
- * <p>\r
- * The main purpose of this class is to enable very easy switching of the\r
- * tracked hint context. Only a call to the {@link #track(IHintContext)} method\r
- * is required. All hint listeners registered into the tracked will\r
- * automatically be switched to listen to the new context instead.\r
- * </p>\r
- * \r
- * <p>\r
- * The tracker is implemented using HintStack but the\r
- * {@link #addHintContext(IHintContext, int)} and\r
- * {@link #removeHintContext(IHintContext)} methods are disabled by throwing\r
- * {@link UnsupportedOperationException} in both. This is to prevent invalid use\r
- * of the class as it is only meant for tracking a single context and nothing\r
- * more. Otherwise this class functions exactly like {@link IHintStack} and\r
- * {@link IHintObservable} are specified to work.\r
- * </p>\r
- * \r
- * <p>\r
- * The implementation is thread-safe.\r
- * </p>\r
- * \r
- * <p>\r
- * Always be sure to {@link #untrack()} any IHintContext that you're tracking\r
- * after the tracker is no longer needed. Otherwise you will most likely have\r
- * invalid listeners within the tracked IHintContext resulting in erroneous\r
- * behavior.\r
- * </p>\r
- * \r
- * @author Tuukka Lehtonen\r
- */\r
-public class HintTracker extends HintStack implements IHintTracker {\r
- \r
- private IHintContext ctx;\r
-\r
- public HintTracker() {\r
- }\r
-\r
- public HintTracker(IHintContext ctx) {\r
- addHintContext(ctx, 0);\r
- }\r
-\r
- /* (non-Javadoc)\r
- * @see org.simantics.utils.datastructures.hints.IHintTracker#track(org.simantics.utils.datastructures.hints.IHintContext)\r
- */\r
- public synchronized final void track(IHintContext ctx) {\r
- IHintContext prevCtx = this.ctx;\r
- if (ctx == prevCtx)\r
- return;\r
- this.ctx = ctx;\r
-\r
- if (ctx != null) {\r
- if (ctx.equals(prevCtx)) {\r
- // remove+add order is necessary in this case.\r
- // add+remove would fail since the hint context would\r
- // already be found in the hint stack.\r
- super.removeHintContext(prevCtx);\r
- super.addHintContext(ctx, 0);\r
- } else {\r
- super.addHintContext(ctx, 0);\r
- if (prevCtx != null)\r
- super.removeHintContext(prevCtx);\r
- }\r
- } else {\r
- if (prevCtx != null)\r
- super.removeHintContext(prevCtx);\r
- }\r
- }\r
- \r
- /* (non-Javadoc)\r
- * @see org.simantics.utils.datastructures.hints.IHintTracker#untrack()\r
- */\r
- public final void untrack() {\r
- track(null);\r
- }\r
- \r
- @Override\r
- public final void addHintContext(IHintContext hints, int priority) {\r
- throw new UnsupportedOperationException();\r
- }\r
-\r
- @Override\r
- public final boolean removeHintContext(IHintContext hints) {\r
- throw new UnsupportedOperationException();\r
- }\r
-\r
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ * VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.utils.datastructures.hints;
+
+/**
+ * HintTracker is a helper class for tracking any hints of a single
+ * IHintContext.
+ *
+ * <p>
+ * The main purpose of this class is to enable very easy switching of the
+ * tracked hint context. Only a call to the {@link #track(IHintContext)} method
+ * is required. All hint listeners registered into the tracked will
+ * automatically be switched to listen to the new context instead.
+ * </p>
+ *
+ * <p>
+ * The tracker is implemented using HintStack but the
+ * {@link #addHintContext(IHintContext, int)} and
+ * {@link #removeHintContext(IHintContext)} methods are disabled by throwing
+ * {@link UnsupportedOperationException} in both. This is to prevent invalid use
+ * of the class as it is only meant for tracking a single context and nothing
+ * more. Otherwise this class functions exactly like {@link IHintStack} and
+ * {@link IHintObservable} are specified to work.
+ * </p>
+ *
+ * <p>
+ * The implementation is thread-safe.
+ * </p>
+ *
+ * <p>
+ * Always be sure to {@link #untrack()} any IHintContext that you're tracking
+ * after the tracker is no longer needed. Otherwise you will most likely have
+ * invalid listeners within the tracked IHintContext resulting in erroneous
+ * behavior.
+ * </p>
+ *
+ * @author Tuukka Lehtonen
+ */
+public class HintTracker extends HintStack implements IHintTracker {
+
+ private IHintContext ctx;
+
+ public HintTracker() {
+ }
+
+ public HintTracker(IHintContext ctx) {
+ addHintContext(ctx, 0);
+ }
+
+ /* (non-Javadoc)
+ * @see org.simantics.utils.datastructures.hints.IHintTracker#track(org.simantics.utils.datastructures.hints.IHintContext)
+ */
+ public synchronized final void track(IHintContext ctx) {
+ IHintContext prevCtx = this.ctx;
+ if (ctx == prevCtx)
+ return;
+ this.ctx = ctx;
+
+ if (ctx != null) {
+ if (ctx.equals(prevCtx)) {
+ // remove+add order is necessary in this case.
+ // add+remove would fail since the hint context would
+ // already be found in the hint stack.
+ super.removeHintContext(prevCtx);
+ super.addHintContext(ctx, 0);
+ } else {
+ super.addHintContext(ctx, 0);
+ if (prevCtx != null)
+ super.removeHintContext(prevCtx);
+ }
+ } else {
+ if (prevCtx != null)
+ super.removeHintContext(prevCtx);
+ }
+ }
+
+ /* (non-Javadoc)
+ * @see org.simantics.utils.datastructures.hints.IHintTracker#untrack()
+ */
+ public final void untrack() {
+ track(null);
+ }
+
+ @Override
+ public final void addHintContext(IHintContext hints, int priority) {
+ throw new UnsupportedOperationException();
+ }
+
+ @Override
+ public final boolean removeHintContext(IHintContext hints) {
+ throw new UnsupportedOperationException();
+ }
+
}
\ No newline at end of file
Code Review / simantics / platform.git / blobdiff