1 package org.apache.maven.shared.filtering;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import java.util.AbstractMap;
23 import java.util.ArrayList;
24 import java.util.Iterator;
25 import java.util.List;
26 import java.util.Map;
27 import java.util.Set;
28
29 /**
30 * A Map composed with some others (optional adding SystemProperties and envvar).
31 * The get method look in the Map list to return the corresponding value.
32 *
33 * @author <a href="mailto:olamy@apache.org">olamy</a>
34 * @version $Id: CompositeMap.java 1055685 2011-01-05 23:14:08Z dennisl $
35 */
36 public class CompositeMap
37 extends AbstractMap
38 {
39
40 private List /*Map*/maps;
41
42 private boolean systemPropertiesFirst;
43
44 /**
45 *
46 * @param maps
47 */
48 public CompositeMap( List /* Map */maps )
49 {
50 this( maps, false, false );
51 }
52
53 /**
54 * @param maps an ordered {@link List} of {@link Map}
55 * @param useSystemProperties using or not the System Properties
56 * @param systemPropertiesFirst if with get( key ) the sysProps must win (the internal ordered {@link List}
57 * will have in first the System Properties)
58 */
59 public CompositeMap( List /*Map*/maps, boolean useSystemProperties, boolean systemPropertiesFirst )
60 {
61 this.systemPropertiesFirst = systemPropertiesFirst;
62 if ( systemPropertiesFirst && !useSystemProperties )
63 {
64 throw new IllegalArgumentException( "systemPropertiesFirst can't be true if useSystemProperties is false" );
65 }
66 this.maps = new ArrayList();
67 if ( useSystemProperties && !systemPropertiesFirst )
68 {
69 if ( maps != null )
70 {
71 this.maps.addAll( maps );
72 }
73 this.maps.add( System.getProperties() );
74 }
75 else if ( useSystemProperties && systemPropertiesFirst )
76 {
77 this.maps.add( System.getProperties() );
78 if ( maps != null )
79 {
80 this.maps.addAll( maps );
81 }
82 }
83 else
84 {
85 if ( maps != null )
86 {
87 this.maps.addAll( maps );
88 }
89 }
90 }
91
92 public Object get( Object key )
93 {
94 if ( this.maps != null )
95 {
96 for ( Iterator iterator = this.maps.iterator(); iterator.hasNext(); )
97 {
98 Map map = (Map) iterator.next();
99 Object value = map.get( key );
100 if ( value != null )
101 {
102 return value;
103 }
104 }
105 }
106 return null;
107 }
108
109 /**
110 * @see java.util.AbstractMap#entrySet()
111 */
112 public Set entrySet()
113 {
114 throw new UnsupportedOperationException( "Cannot enumerate properties in a composite map" );
115 }
116
117 public List getMaps()
118 {
119 return maps;
120 }
121
122 public void addMap( Map map )
123 {
124 // see constructors internal Map can't be null
125 this.maps.add( map );
126 }
127
128 public boolean isSystemPropertiesFirst()
129 {
130 return systemPropertiesFirst;
131 }
132
133 public void setSystemPropertiesFirst( boolean systemPropertiesFirst )
134 {
135 this.systemPropertiesFirst = systemPropertiesFirst;
136 }
137
138 }