1 files changed, 66 insertions, 0 deletions
diff --git a/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/provisional/p2/ui/query/LatestIUVersionCollector.java b/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/provisional/p2/ui/query/LatestIUVersionCollector.java
new file mode 100644
index 000000000..6a0c1fd94
--- /dev/null
+++ b/bundles/org.eclipse.equinox.p2.ui/src/org/eclipse/equinox/internal/provisional/p2/ui/query/LatestIUVersionCollector.java
@@ -0,0 +1,66 @@
+/*******************************************************************************
+ * Copyright (c) 2008 IBM Corporation and others.
+ * 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:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.equinox.internal.provisional.p2.ui.query;
+
+import java.util.HashMap;
+import org.eclipse.equinox.internal.provisional.p2.metadata.IInstallableUnit;
+import org.eclipse.equinox.internal.provisional.p2.query.IQueryable;
+
+/**
+ * Collector that only accepts categories or the latest version of each
+ * IU.
+ * 
+ * @since 3.4
+ */
+public class LatestIUVersionCollector extends AvailableIUCollector {
+
+	private HashMap uniqueIds = new HashMap();
+
+	public LatestIUVersionCollector(IQueryProvider queryProvider, IQueryable queryable, boolean makeCategories) {
+		super(queryProvider, queryable, makeCategories);
+	}
+
+	/**
+	 * Accepts a result that matches the query criteria.
+	 * 
+	 * @param match an object matching the query
+	 * @return <code>true</code> if the query should continue,
+	 * or <code>false</code> to indicate the query should stop.
+	 */
+	public boolean accept(Object match) {
+		if (!(match instanceof IInstallableUnit))
+			return true;
+		IInstallableUnit iu = (IInstallableUnit) match;
+		// If it's a category, treat it as such if we are to build categories
+		if (makeCategory() && isCategory(iu))
+			return super.accept(match);
+		// Look for the latest element
+		Object matchElement = uniqueIds.get(iu.getId());
+		if (matchElement == null || iu.getVersion().compareTo(getIU(matchElement).getVersion()) > 0) {
+			if (matchElement != null)
+				getList().remove(matchElement);
+			matchElement = makeDefaultElement(iu);
+			uniqueIds.put(iu.getId(), matchElement);
+			return super.accept(matchElement);
+		}
+		return true;
+	}
+
+	protected Object makeDefaultElement(IInstallableUnit iu) {
+		return iu;
+	}
+
+	protected IInstallableUnit getIU(Object matchElement) {
+		if (matchElement instanceof IInstallableUnit)
+			return (IInstallableUnit) matchElement;
+		return null;
+	}
+}