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Java > Open Source Codes > bsh > classpath > DiscreteFilesClassLoader


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12  * The Original Code is BeanShell. The Initial Developer of the Original *
13  * Code is Pat Niemeyer. Portions created by Pat Niemeyer are Copyright *
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33
34 package bsh.classpath;
35
36 import java.io.*;
37 import java.io.File JavaDoc;
38 import java.util.*;
39 import java.awt.*;
40 import bsh.BshClassManager;
41 import bsh.classpath.BshClassPath.ClassSource;
42 import bsh.classpath.BshClassPath.DirClassSource;
43 import bsh.classpath.BshClassPath.GeneratedClassSource;
44
45 /**
46     A classloader which can load one or more classes from specified sources.
47     Because the classes are loaded via a single classloader they change as a
48     group and any versioning cross dependencies can be managed.
49 */
50 public class DiscreteFilesClassLoader extends BshClassLoader
51 {
52     /**
53         Map of class sources which also implies our coverage space.
54     */
55     ClassSourceMap map;
56
57     public static class ClassSourceMap extends HashMap
58     {
59         public void put( String JavaDoc name, ClassSource source ) {
60             super.put( name, source );
61         }
62         public ClassSource get( String JavaDoc name ) {
63             return (ClassSource)super.get( name );
64         }
65     }
66     
67     public DiscreteFilesClassLoader(
68         BshClassManager classManager, ClassSourceMap map )
69     {
70         super( classManager );
71         this.map = map;
72     }
73
74     /**
75     */
76     public Class JavaDoc findClass( String JavaDoc name ) throws ClassNotFoundException JavaDoc
77     {
78         // Load it if it's one of our classes
79 ClassSource source = map.get( name );
80
81         if ( source != null )
82         {
83             byte [] code = source.getCode( name );
84             return defineClass( name, code, 0, code.length );
85         } else
86             // Let superclass BshClassLoader (URLClassLoader) findClass try
87 // to find the class...
88 return super.findClass( name );
89     }
90
91     public String JavaDoc toString() {
92         return super.toString() + "for files: "+map;
93     }
94
95 }
96
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