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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.Collections ;
28
29 import java.lang.reflect.Array ;
30
31 import com.sun.appserv.management.util.misc.ClassUtil;
32
33
38 public final class ArrayConversion
39 {
40 private
41 ArrayConversion( )
42 {
43 }
45
46 private static Object []
47 convert( Object simpleArray )
48 {
49 if ( ! ClassUtil.objectIsPrimitiveArray( simpleArray ) )
50 {
51 throw new IllegalArgumentException ();
52 }
53
54 final String className = simpleArray.getClass().getName();
55
56 final Class theClass = ClassUtil.getArrayElementClass( simpleArray.getClass() );
57
58 final int numItems = Array.getLength( simpleArray );
59
60 final Class elementClass = ClassUtil.PrimitiveClassToObjectClass( theClass );
61
62 final Object [] result = (Object [])Array.newInstance( elementClass, numItems );
63
64 for( int i = 0; i < numItems; ++i )
65 {
66 result[ i ] = Array.get( simpleArray, i );
67 }
68
69 return( result );
70 }
71
72
78 public static Object []
79 toAppropriateType( Object array)
80 {
81 return( (Object [])convert( array ) );
82 }
83
84
85 public static Boolean []
86 toBooleans( boolean [] array )
87 {
88 return( (Boolean [])convert( array ) );
89 }
90
91 public static Character []
92 toCharacters( char [] array )
93 {
94 return( (Character [])convert( array ) );
95 }
96
97 public static Byte []
98 toBytes( byte [] array )
99 {
100 return( (Byte [])convert( array ) );
101 }
102
103 public static Short []
104 toShorts( short [] array )
105 {
106 return( (Short [])convert( array ) );
107 }
108
109 public static Integer []
110 toIntegers( int [] array )
111 {
112 return( (Integer [])convert( array ) );
113 }
114
115 public static Long []
116 toLongs( long [] array )
117 {
118 return( (Long [])convert( array ) );
119 }
120
121 public static Float []
122 toFloats( float [] array )
123 {
124 return( (Float [])convert( array ) );
125 }
126
127 public static Double []
128 toDoubles( double [] array )
129 {
130 return( (Double [])convert( array ) );
131 }
132
133
134
140 public static Object []
141 createObjectArrayType( final Class elementType, final int size )
142 {
143 final Object [] result = (Object []) Array.newInstance( elementType, size );
144
145 return( result );
146 }
147
148 public static Object []
149 subArray( final Object [] in, int start, int end )
150 {
151 final int count = 1 + (end - start);
152 final Object [] result = (Object [])
153 Array.newInstance( ClassUtil.getArrayElementClass( in.getClass() ), count );
154
155 for( int i = 0; i < count; ++i )
156 {
157 result[ i ] = in[ i + start ];
158 }
159
160 return( result );
161 }
162
163
164
165 public static <T> Set <T>
166 toSet( T[] array )
167 {
168 Set <T> theSet = null;
169 if ( array.length == 0 )
170 {
171 theSet = Collections.emptySet();
172 }
173 else if ( array.length == 1 )
174 {
175 theSet = Collections.singleton( array[ 0 ] );
176 }
177 else
178 {
179 theSet = new HashSet <T>();
180 for( int i = 0; i < array.length; ++i )
181 {
182 theSet.add( array[ i ] );
183 }
184 }
185 return( theSet );
186 }
187
188
189
192 public static boolean
193 hasIdenticalElementClasses( final Object [] a )
194 {
195 boolean isUniform = true;
196
197 if ( a.length > 0 )
198 {
199 final Class matchType = a[ 0 ].getClass();
200
201 for( int i = 1; i < a.length; ++i )
202 {
203 if ( a[ i ].getClass() != matchType )
204 {
205 isUniform = false;
206 break;
207 }
208 }
209 }
210
211 return( isUniform );
212 }
213
214
221 public static Object []
222 specializeArray( final Object [] a )
223 {
224 Object [] result = a;
225
226 if ( hasIdenticalElementClasses( a ) &&
227 a.length != 0 &&
228 a.getClass() == Object [].class )
229 {
230 result = createObjectArrayType( a[0].getClass(), a.length );
231
232 System.arraycopy( a, 0, result, 0, a.length );
233 }
234
235 return( result );
236 }
237
238
245 public static Object []
246 setToArray( final Set <?> s, boolean specialize )
247 {
248 Object [] result = setToArray( s );
249
250 if ( specialize && result.length != 0)
251 {
252 result = specializeArray( result );
253 }
254
255 return( result );
256 }
257
258
263 public static Object []
264 setToArray( final Set <?> s )
265 {
266 final Object [] out = new Object [ s.size() ];
267
268 setToArray( s, out );
269
270 return( out );
271 }
272
273
274
280 public static Object []
281 setToArray( final Set <?> s, Object [] out )
282 {
283 if ( out.length != s.size() )
284 {
285 throw new IllegalArgumentException ();
286 }
287
288 int i = 0;
289 for( final Object o : s )
290 {
291 out[ i ] = o;
292 ++i;
293 }
294
295 return( out );
296 }
297
298
299 public static <T> Set <T>
300 arrayToSet( final T [] names )
301 {
302 final Set <T> set = new HashSet <T>();
303
304 for( int i = 0; i < names.length; ++i )
305 {
306 set.add( names[ i ] );
307 }
308
309 return( set );
310 }
311 }
312
313 |
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