org.apache.commons.exec.util.MapUtils Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
*/
package org.apache.commons.exec.util;
import java.util.Map;
import java.util.HashMap;
import java.util.Iterator;
/**
* Helper classes to manipulate maps to pass substition map to the
* CommandLine. This class is not part of the public API and
* could change without warning.
*
* @author Siegfried Goeschl
*/
public class MapUtils
{
/**
* Clones a map.
*
* @param source the source map
* @return the clone of the source map
*/
public static Map copy(final Map source) {
if (source == null) {
return null;
}
final Map result = new HashMap();
result.putAll(source);
return result;
}
/**
* Clones a map and prefixes the keys in the clone, e.g.
* for mapping "JAVA_HOME" to "env.JAVA_HOME" to simulate
* the behaviour of ANT.
*
* @param source the source map
* @param prefix the prefix used for all names
* @return the clone of the source map
*/
public static Map prefix(final Map source, final String prefix) {
if (source == null) {
return null;
}
final Map result = new HashMap();
final Iterator iter = source.entrySet().iterator();
while (iter.hasNext()) {
final Map.Entry entry = (Map.Entry) iter.next();
final Object key = entry.getKey();
final Object value = entry.getValue();
result.put(prefix + '.' + key.toString(), value);
}
return result;
}
/**
* Clones the lhs map and add all things from the
* rhs map.
*
* @param lhs the first map
* @param rhs the second map
* @return the merged map
*/
public static Map merge(final Map lhs, final Map rhs) {
Map result = null;
if (lhs == null || lhs.size() == 0) {
result = copy(rhs);
}
else if (rhs == null || rhs.size() == 0) {
result = copy(lhs);
}
else {
result = copy(lhs);
result.putAll(rhs);
}
return result;
}
}