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diff --git a/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/prov/core/helpers/OrderedProperties.java b/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/prov/core/helpers/OrderedProperties.java
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+++ b/bundles/org.eclipse.equinox.p2.core/src/org/eclipse/equinox/prov/core/helpers/OrderedProperties.java
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+/*******************************************************************************
+ * Copyright (c) 2007 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.prov.core.helpers;
+
+import java.util.*;
+
+/**
+ * A Properties collection that maintains the order of insertion.
+ * <p>
+ * This class is used to store properties similar to {@link java.util.Properties}.
+ * In particular both keys and values are strings and must be not null.
+ * However this class is somewhat simplified and does not implement Cloneable, 
+ * Serializable and Hashtable.
+ * <p>
+ * In contrast to java.util.Properties this class maintains the order by which 
+ * properties are added. This is implemented using a {@link LinkedHashMap}.
+ * <p>
+ * The class does not support default properties as they can be expressed by 
+ * creating java.util.Properties hierarchies.
+ */
+public class OrderedProperties implements Map {
+
+	private LinkedHashMap propertyMap = null;
+
+	private static final String[] NO_KEYS = new String[0];
+
+	public OrderedProperties() {
+		super();
+	}
+
+	/**
+	 * Set the property value.
+	 * <p>
+	 * If a property with the key already exists, the previous
+	 * value is replaced. Otherwise a new property is added at
+	 * the end collection.
+	 * 
+	 * @param key   must not be null
+	 * @param value must not be null
+	 * @return previous value associated with specified key, or <tt>null</tt>
+	 *	       if there was no mapping for key.
+	 */
+	public Object setProperty(String key, String value) {
+		init();
+		return propertyMap.put(key, value);
+	}
+
+	public String getProperty(String key) {
+		return (String) (propertyMap == null ? null : propertyMap.get(key));
+	}
+
+	public String getProperty(String key, String defaultValue) {
+		String value = getProperty(key);
+		return (value == null) ? defaultValue : value;
+	}
+
+	public void putAll(OrderedProperties properties) {
+		putAll((Map) properties);
+	}
+
+	public Collection getPropertyKeysCollection() {
+		if (propertyMap == null)
+			return Collections.EMPTY_LIST;
+		return Collections.unmodifiableCollection(propertyMap.keySet());
+	}
+
+	public String[] getPropertyKeys() {
+		if (propertyMap == null)
+			return NO_KEYS;
+		Collection keySet = propertyMap.keySet();
+		return (String[]) keySet.toArray(new String[keySet.size()]);
+	}
+
+	/**
+	 *	Initialize the map.
+	 */
+	private void init() {
+		if (propertyMap == null) {
+			propertyMap = new LinkedHashMap();
+		}
+	}
+
+	public int size() {
+		return propertyMap == null ? 0 : propertyMap.size();
+	}
+
+	public boolean isEmpty() {
+		return propertyMap == null ? true : propertyMap.isEmpty();
+	}
+
+	public synchronized void clear() {
+		propertyMap = null;
+	}
+
+	public Object put(Object arg0, Object arg1) {
+		init();
+		return propertyMap.put(arg0, arg1);
+	}
+
+	public boolean containsKey(Object key) {
+		return propertyMap != null ? propertyMap.containsKey(key) : false;
+	}
+
+	public boolean containsValue(Object value) {
+		return propertyMap != null ? propertyMap.containsValue(value) : false;
+	}
+
+	public Set entrySet() {
+		return propertyMap != null ? propertyMap.entrySet() : Collections.EMPTY_SET;
+	}
+
+	public Object get(Object key) {
+		return propertyMap != null ? propertyMap.get(key) : null;
+	}
+
+	public Set keySet() {
+		return propertyMap != null ? propertyMap.keySet() : Collections.EMPTY_SET;
+	}
+
+	public void putAll(Map arg0) {
+		init();
+		propertyMap.putAll(arg0);
+	}
+
+	public Object remove(Object key) {
+		return propertyMap != null ? propertyMap.remove(key) : null;
+	}
+
+	public Collection values() {
+		return propertyMap != null ? propertyMap.values() : Collections.EMPTY_LIST;
+	}
+
+	public boolean equals(Object o) {
+		if (o == this)
+			return true;
+		if (o instanceof OrderedProperties) {
+			OrderedProperties rhs = (OrderedProperties) o;
+			if (rhs.propertyMap == this.propertyMap)
+				return true;
+			if (rhs.propertyMap == null || this.propertyMap == null)
+				return false;
+			return rhs.propertyMap.equals(this.propertyMap);
+		}
+		return propertyMap.equals(o);
+	}
+
+	public int hashCode() {
+		return propertyMap != null ? propertyMap.hashCode() : 0;
+	}
+
+	public String toString() {
+		StringBuffer sb = new StringBuffer();
+		sb.append(propertyMap);
+		return sb.toString();
+	}
+
+}