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1
22
23
24 package com.mchange.v1.lang;
25
26 import java.util.*;
27 import com.mchange.v1.jvm.*;
28
29 public final class ClassUtils
30 {
31 final static String  [] EMPTY_SA = new String [0];
32
33 static Map primitivesToClasses;
34
35 static
36 {
37 HashMap tmp = new HashMap();
38 tmp.put( "boolean", boolean.class );
39 tmp.put( "int", int.class );
40 tmp.put( "char", char.class );
41 tmp.put( "short", short.class );
42 tmp.put( "int", int.class );
43 tmp.put( "long", long.class );
44 tmp.put( "float", float.class );
45 tmp.put( "double", double.class );
46 tmp.put( "void", void.class );
47
48 primitivesToClasses = Collections.unmodifiableMap( tmp );
49 }
50
51 public static Set allAssignableFrom(Class type)
52 {
53 Set out = new HashSet();
54
55 for (Class cl = type; cl != null; cl = cl.getSuperclass())
57 out.add( cl );
58
59 addSuperInterfacesToSet( type, out );
61 return out;
62 }
63
64 public static String simpleClassName(Class cl)
65 {
66 String scn;
67 int array_level = 0;
68 while (cl.isArray())
69 {
70 ++array_level;
71 cl = cl.getComponentType();
72 }
73 scn = simpleClassName( cl.getName() );
74 if ( array_level > 0 )
75 {
76 StringBuffer sb = new StringBuffer (16);
77 sb.append( scn );
78 for( int i = 0; i < array_level; ++i)
79 sb.append("[]");
80 return sb.toString();
81 }
82 else
83 return scn;
84 }
85
86 private static String simpleClassName(String fqcn)
87 {
88 int pkgdot = fqcn.lastIndexOf('.');
89 if (pkgdot < 0)
90 return fqcn;
91 String scn = fqcn.substring(pkgdot + 1);
92 if (scn.indexOf('$') >= 0)
93 {
94 StringBuffer sb = new StringBuffer (scn);
95 for (int i = 0, len = sb.length(); i < len; ++i)
96 {
97 if (sb.charAt(i) == '$')
98 sb.setCharAt(i, '.');
99 }
100 return sb.toString();
101 }
102 else
103 return scn;
104 }
105
106 public static boolean isPrimitive(String typeStr)
107 { return (primitivesToClasses.get( typeStr ) != null); }
108
109 public static Class classForPrimitive(String typeStr)
110 { return (Class ) primitivesToClasses.get( typeStr ); }
111
112 public static Class forName(String fqcnOrPrimitive ) throws ClassNotFoundException
113 {
114 Class out = classForPrimitive( fqcnOrPrimitive );
115 if (out == null)
116 out = Class.forName( fqcnOrPrimitive );
117 return out;
118 }
119
120 public static Class forName( String fqOrSimple, String [] importPkgs, String [] importClasses )
121 throws AmbiguousClassNameException, ClassNotFoundException
122 {
123 try
124 { return Class.forName( fqOrSimple ); }
125 catch ( ClassNotFoundException e )
126 { return classForSimpleName( fqOrSimple, importPkgs, importClasses ); }
127 }
128
129 public static Class classForSimpleName( String simpleName, String [] importPkgs, String [] importClasses )
130 throws AmbiguousClassNameException, ClassNotFoundException
131 {
132 Set checkSet = new HashSet();
133 Class out = classForPrimitive( simpleName );
134
135 if (out == null)
136 {
137 if (importPkgs == null)
138 importPkgs = EMPTY_SA;
139
140 if (importClasses == null)
141 importClasses = EMPTY_SA;
142
143 for (int i = 0, len = importClasses.length; i < len; ++i)
144 {
145 String importSimpleName = fqcnLastElement( importClasses[i] );
146 if (! checkSet.add( importSimpleName ) )
147 throw new IllegalArgumentException ("Duplicate imported classes: " +
148 importSimpleName);
149 if ( simpleName.equals( importSimpleName ) )
150 out = Class.forName( importClasses[i] );
152 }
153 if (out == null)
154 {
155 try { out = Class.forName("java.lang." + simpleName); }
156 catch (ClassNotFoundException e)
157 { }
158
159 for (int i = 0, len = importPkgs.length; i < len; ++i)
160 {
161 try
162 {
163 String tryClass = importPkgs[i] + '.' + simpleName;
164 Class test = Class.forName( tryClass );
165 if ( out == null )
166 out = test;
167 else
168 throw new AmbiguousClassNameException( simpleName, out, test );
169 }
170 catch (ClassNotFoundException e)
171 { }
172 }
173 }
174 }
175 if (out == null)
176 throw new ClassNotFoundException ( "Could not find a class whose unqualified name is \042" +
177 simpleName + "\042 with the imports supplied. Import packages are " +
178 Arrays.asList( importPkgs ) + "; class imports are " +
179 Arrays.asList( importClasses ) );
180 else
181 return out;
182 }
183
184 public static String resolvableTypeName( Class type, String [] importPkgs, String [] importClasses )
185 throws ClassNotFoundException
186 {
187 String simpleName = simpleClassName( type );
188 try
189 { classForSimpleName( simpleName, importPkgs, importClasses ); }
190 catch ( AmbiguousClassNameException e )
191 { return type.getName(); }
192 return simpleName;
193 }
194
195 public static String fqcnLastElement(String fqcn)
196 {
197 int pkgdot = fqcn.lastIndexOf('.');
198 if (pkgdot < 0)
199 return fqcn;
200 return fqcn.substring(pkgdot + 1);
201 }
202
203
204
205 private static void addSuperInterfacesToSet(Class type, Set set)
206 {
207 Class [] ifaces = type.getInterfaces();
208 for (int i = 0, len = ifaces.length; i < len; ++i)
209 {
210 set.add( ifaces[i] );
211 addSuperInterfacesToSet( ifaces[i], set );
212 }
213 }
214
215 private ClassUtils()
216 {}
217 }
218 |
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