1 files changed, 109 insertions, 0 deletions
diff --git a/qt/org.eclipse.cdt.qt.core/src/org/eclipse/cdt/internal/qt/core/pdom/QtPDOMVisitor.java b/qt/org.eclipse.cdt.qt.core/src/org/eclipse/cdt/internal/qt/core/pdom/QtPDOMVisitor.java
new file mode 100644
index 00000000000..867b2ac1944
--- /dev/null
+++ b/qt/org.eclipse.cdt.qt.core/src/org/eclipse/cdt/internal/qt/core/pdom/QtPDOMVisitor.java
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2013 QNX Software Systems 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
+ */
+package org.eclipse.cdt.internal.qt.core.pdom;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+
+import org.eclipse.cdt.core.dom.IPDOMNode;
+import org.eclipse.cdt.core.dom.IPDOMVisitor;
+import org.eclipse.cdt.internal.core.pdom.dom.PDOMNamedNode;
+import org.eclipse.core.runtime.CoreException;
+
+/**
+ * A Qt-specific specialization of the generic PDOMVisitor.  This class provides
+ * an empty implementation of {@link #leave(IPDOMNode)}, but required implementations to
+ * provide {@link #visit(IPDOMNode)}.  The class also provides a few commonly required
+ * implementations.
+ */
+@SuppressWarnings("restriction")
+public abstract class QtPDOMVisitor implements IPDOMVisitor {
+
+	/**
+	 * Collects all nodes that match the given type.  This could be used, for example, to get
+	 * all QtPDOMQObject's from the index.
+	 */
+	public static class All<T> extends QtPDOMVisitor {
+
+		private final Class<T> cls;
+		public final ArrayList<T> list = new ArrayList<T>();
+
+		public All(Class<T> cls) {
+			this.cls = cls;
+		}
+
+		@Override
+		@SuppressWarnings("unchecked")
+		public boolean visit(IPDOMNode node) throws CoreException {
+			if (node != null
+			 && cls.isAssignableFrom(node.getClass()))
+				list.add((T) node);
+			return true;
+		}
+	}
+
+	/**
+	 * A simple interface that is used to select node's from the index based on specific
+	 * criteria.
+	 */
+	public static interface IFilter {
+		public boolean matches(IPDOMNode node) throws CoreException;
+	}
+
+	/**
+	 * A filter that selects nodes based on their name.
+	 */
+	public static class PDOMNamedNodeFilter implements IFilter {
+
+		private final char[] name;
+
+		public PDOMNamedNodeFilter(String name) {
+			this.name = name.toCharArray();
+		}
+
+		@Override
+		public boolean matches(IPDOMNode node) throws CoreException {
+			if (node instanceof PDOMNamedNode)
+				return Arrays.equals(name, ((PDOMNamedNode) node).getNameCharArray());
+			return false;
+		}
+	}
+
+	/**
+	 * A utility class that searches the index for all nodes that match the given filter.
+	 */
+	public static class Find<T> extends QtPDOMVisitor {
+
+		private final Class<T> cls;
+		private final IFilter filter;
+
+		public T element;
+
+		public Find(Class<T> cls, IFilter filter) {
+			this.cls = cls;
+			this.filter = filter;
+		}
+
+		@Override
+		@SuppressWarnings("unchecked")
+		public boolean visit(IPDOMNode node) throws CoreException {
+			if (element != null)
+				return false;
+
+			if (cls.isAssignableFrom(node.getClass())
+			 && filter.matches(node))
+				element = (T) node;
+
+			return element == null;
+		}
+	}
+
+	@Override
+	public void leave(IPDOMNode node) throws CoreException {
+	}
+}