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1
23 package com.sun.appserv.management.util.misc;
24
25 import java.util.Set  ;
26 import java.util.HashSet ;
27 import java.util.Iterator ;
28 import java.util.Map ;
29 import java.util.HashMap ;
30 import java.util.Properties ;
31
32 import com.sun.appserv.management.util.stringifier.SmartStringifier;
33
34
35 public final class MapUtil
36 {
37 private
38 MapUtil( )
39 {
40 }
42
43 public static <K,V> V
44 getWithDefault( final Map <K,V> m, final K key, V defaultValue )
45 {
46 return m.containsKey( key ) ? m.get( key ) : defaultValue;
47 }
48
49
50 public static Object []
51 getKeyObjects( final Map <?,?> m)
52 {
53 return( SetUtil.toArray( m.keySet() ) );
54 }
55
56 public static String []
57 getKeyStrings( final Map <?,?> m)
58 {
59 return( GSetUtil.toSortedStringArray( m.keySet() ) );
60 }
61
62
65 public static <V> Map <String ,V>
66 newMap(
67 final String key,
68 final V value )
69 {
70 final Map <String ,V> m = new HashMap <String ,V>();
71
72 m.put( key, value );
73
74 return( m );
75 }
76
77
80 public static <K,V> Map <K,V>
81 newMap(
82 final Map <K,V> m1,
83 final Map <K,V> m2 )
84 {
85 final Map <K,V> m = new HashMap <K,V>();
86
87 if ( m1 != null )
88 {
89 m.putAll( m1 );
90 }
91 if ( m2 != null )
92 {
93 m.putAll( m2 );
94 }
95
96 return( m );
97 }
98
99
104 public static <T> Map <T,T>
105 newMap( final T[] mappings )
106 {
107 if ( (mappings.length % 2) != 0 )
108 {
109 throw new IllegalArgumentException ( "mappings must have even length" );
110 }
111
112 final Map <T,T> m = new HashMap <T,T>();
113
114 for( int i = 0; i < mappings.length; i += 2 )
115 {
116 m.put( mappings[ i ], mappings[ i + 1 ] );
117 }
118
119 return( m );
120 }
121
122
127 public static Map <String ,String >
128 newMap( final String [] mappings )
129 {
130 if ( (mappings.length % 2) != 0 )
131 {
132 throw new IllegalArgumentException ( "mappings must have even length" );
133 }
134
135 final Map <String ,String > m = new HashMap <String ,String >();
136
137 for( int i = 0; i < mappings.length; i += 2 )
138 {
139 m.put( mappings[ i ], mappings[ i + 1 ] );
140 }
141
142 return( m );
143 }
144
145
146
149 public static <T> void
150 removeAll(
151 final Map <T,?> m,
152 final T[] keys )
153 {
154 for( int i = 0; i < keys.length; ++i )
155 {
156 m.remove( keys[ i ] );
157 }
158 }
159
160 public static boolean
161 mapsEqual(
162 final Map <?,?> m1,
163 final Map <?,?> m2 )
164 {
165 if ( m1 == m2 )
166 {
167 return( true );
168 }
169
170 boolean equal = false;
171
172 if ( m1.size() == m2.size() &&
173 m1.keySet().equals( m2.keySet() ) )
174 {
175 equal = true;
176
177 for( final Object key : m1.keySet() )
178 {
179 final Object value1 = m1.get( key );
180 final Object value2 = m2.get( key );
181
182 if ( ! CompareUtil.objectsEqual( value1, value2 ) )
183 {
184 equal = false;
185 break;
186 }
187 }
188 }
189
190 return( equal );
191 }
192
193
194 public static <K,V> Map <K,V>
195 newMapNoNullValues( final Map <K,V> m )
196 {
197 final Map <K,V> result = new HashMap <K,V>();
198
199 for ( final K key : m.keySet() )
200 {
201 final V value = m.get( key );
202
203 if ( value != null )
204 {
205 result.put( key, value );
206 }
207 }
208
209 return( result );
210 }
211
212 public static String
213 toString( final Map <?,?> m )
214 {
215 return( toString( m, "," ) );
216 }
217
218 public static String
219 toString( final Map <?,?> m, final String separator )
220 {
221 if ( m == null )
222 {
223 return( "null" );
224 }
225
226 final StringBuffer buf = new StringBuffer ();
227
228 final String [] keyStrings = getKeyStrings( m );
229 for( final String key : keyStrings )
230 {
231 final Object value = m.get( key );
232
233 buf.append( key );
234 buf.append( "=" );
235 buf.append( SmartStringifier.toString( value ) );
236 buf.append( separator );
237 }
238 if ( buf.length() != 0 )
239 {
240 buf.setLength( buf.length() - separator.length() );
242 }
243
244 return( buf.toString() );
245 }
246
247 public static <K> Set <K>
248 getNullValueKeys( final Map <K,?> m)
249 {
250 final Set <K> s = new HashSet <K>();
251
252 for( final K key : m.keySet() )
253 {
254 if ( m.get( key ) == null )
255 {
256 s.add( key );
257 }
258 }
259 return( s );
260 }
261
262
263 public static <K,V> Map <K,V>
264 toMap( final Properties props, final Class <K> kClass, final Class <V> vClass)
265 {
266 return TypeCast.checkMap( props, kClass, vClass );
267 }
268
269 public static <K> void
270 removeAll( final Map <K,?> m, final Set <K> s )
271 {
272 for( final K key : s )
273 {
274 m.remove( key );
275 }
276 }
277
278
281 public static boolean
282 isAllStrings( final Map <?,?> m )
283 {
284 return m != null && CollectionUtil.isAllStrings( m.keySet() ) &&
285 CollectionUtil.isAllStrings( m.values() );
286 }
287
288
292 public static Map <String ,String >
293 toStringStringMap( final Map <?,?> m )
294 {
295 if ( m == null )
296 {
297 return null;
298 }
299
300 Map <String ,String > result = null;
301
302 if ( isAllStrings( m ) )
303 {
304 result = TypeCast.asMap( m );
305 }
306 else
307 {
308 result = new HashMap <String ,String >();
309
310 for( final Object key : m.keySet() )
311 {
312 final Object value = m.get( key );
313
314 if ( (key instanceof String ) && (value instanceof String ) )
315 {
316 result.put( (String )key, (String )value );
317 }
318 else
319 {
320 result.put( "" + key, "" + value );
321 }
322 }
323 }
324
325 return result;
326 }
327 }
328
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339 |
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