1 files changed, 48 insertions, 0 deletions
diff --git a/bundles/org.eclipse.equinox.p2.metadata/src/org/eclipse/equinox/internal/p2/metadata/query/UpdateQuery.java b/bundles/org.eclipse.equinox.p2.metadata/src/org/eclipse/equinox/internal/p2/metadata/query/UpdateQuery.java
new file mode 100644
index 000000000..3ca68f9a0
--- /dev/null
+++ b/bundles/org.eclipse.equinox.p2.metadata/src/org/eclipse/equinox/internal/p2/metadata/query/UpdateQuery.java
@@ -0,0 +1,48 @@
+/*******************************************************************************
+ *  Copyright (c) 2008, 2009 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.p2.metadata.query;
+
+import org.eclipse.equinox.p2.metadata.IUpdateDescriptor;
+
+import org.eclipse.equinox.p2.metadata.IInstallableUnitPatch;
+
+import org.eclipse.equinox.p2.metadata.IInstallableUnit;
+import org.eclipse.equinox.p2.metadata.IRequirement;
+import org.eclipse.equinox.p2.query.MatchQuery;
+
+/**
+ * A query that finds all IUs that are considered an "Update" of the 
+ * specified IU.  
+ */
+public class UpdateQuery extends MatchQuery<IInstallableUnit> {
+	private IInstallableUnit updateFrom;
+
+	public UpdateQuery(IInstallableUnit updateFrom) {
+		this.updateFrom = updateFrom;
+	}
+
+	public boolean isMatch(IInstallableUnit candidate) {
+		if (candidate instanceof IInstallableUnitPatch && !(updateFrom instanceof IInstallableUnitPatch)) {
+			IInstallableUnitPatch potentialPatch = (IInstallableUnitPatch) candidate;
+			IRequirement lifeCycle = potentialPatch.getLifeCycle();
+			if (lifeCycle == null)
+				return false;
+			return updateFrom.satisfies(lifeCycle);
+		}
+		IUpdateDescriptor descriptor = candidate.getUpdateDescriptor();
+		if (descriptor != null && descriptor.isUpdateOf(updateFrom)) {
+			if (!updateFrom.getId().equals(candidate.getId()))
+				return true;
+			return updateFrom.getVersion().compareTo(candidate.getVersion()) < 0;
+		}
+		return false;
+	}
+}