tests/regression/resolving/TestLoader.java

   1 import java.util.Hashtable;
   2 import java.io.*;
   3
   4 public class TestLoader extends ClassLoader {
   5
   6     Hashtable registry_;
   7     String name_;
   8     TestController controller_;
   9
  10     class Entry {
  11     }
  12
  13     class ClassfileEntry extends Entry {
  14         public String filename_;
  15         public ClassfileEntry(String filename) { filename_ = filename; }
  16     }
  17
  18     class DelegationEntry extends Entry {
  19         public ClassLoader loader_;
  20         public DelegationEntry(ClassLoader loader) { loader_ = loader; }
  21     }
  22
  23     class SuperDelegationEntry extends Entry {
  24     }
  25
  26     public TestLoader(ClassLoader parent, String name, TestController controller) {
  27         super(parent);
  28         name_ = name;
  29         controller_ = controller;
  30         registry_ = new Hashtable();
  31     }
  32
  33     public void addClassfile(String classname, String filename) {
  34         registry_.put(classname, new ClassfileEntry(filename));
  35     }
  36
  37     public void addDelegation(String classname, ClassLoader loader) {
  38         registry_.put(classname, new DelegationEntry(loader));
  39     }
  40
  41     public void addParentDelegation(String classname) {
  42         registry_.put(classname, new DelegationEntry(getParent()));
  43     }
  44
  45     public void addSuperDelegation(String classname) {
  46         registry_.put(classname, new SuperDelegationEntry());
  47     }
  48
  49     public String toString() {
  50         return "TestLoader<" + name_ + ">";
  51     }
  52
  53     public Class loadClass(String classname) throws ClassNotFoundException {
  54         controller_.reportRequest(this, classname);
  55
  56         Entry entry = (Entry) registry_.get(classname);
  57
  58         if (entry == null) {
  59             controller_.reportUnexpectedClassRequested(this, classname);
  60             throw new ClassNotFoundException(this + " does not know how to load class " + classname);
  61         }
  62
  63         if (entry instanceof ClassfileEntry) {
  64             Class cls = findLoadedClass(classname);
  65
  66             if (cls != null) {
  67                 controller_.reportFoundLoaded(this, cls);
  68                 return cls;
  69             }
  70
  71             String filename = ((ClassfileEntry)entry).filename_;
  72
  73             try {
  74                 byte[] bytes = slurpFile(filename);
  75
  76                 cls = defineClass(classname, bytes, 0, bytes.length);
  77
  78                 controller_.reportDefinition(this, cls);
  79
  80                 return cls;
  81             }
  82             catch (Exception e) {
  83                 throw new ClassNotFoundException(e.toString());
  84             }
  85         }
  86         else if (entry instanceof DelegationEntry) {
  87             ClassLoader delegate = ((DelegationEntry)entry).loader_;
  88
  89             controller_.reportDelegation(this, delegate, classname);
  90
  91             Class cls = delegate.loadClass(classname);
  92
  93             controller_.reportLoaded(this, cls);
  94
  95             return cls;
  96         }
  97
  98         throw new ClassNotFoundException("unknown TestLoader entry: " + entry);
  99     }
 100
 101     byte[] slurpFile(String filename) throws IOException {
 102         File file = new File(filename);
 103         InputStream is = new FileInputStream(file);
 104         long len = file.length();
 105         if (len > Integer.MAX_VALUE)
 106             throw new IOException("file " + file.getName() + " is too large");
 107         byte[] bytes = new byte[(int) len];
 108
 109         int ofs = 0;
 110         int read = 0;
 111         while ((ofs < len) && (read = is.read(bytes, ofs, bytes.length - ofs)) >= 0)
 112             ofs += read;
 113
 114         if (ofs < len)
 115             throw new IOException("error reading file " + file.getName());
 116
 117         is.close();
 118         return bytes;
 119     }
 120 }
 121
 122 // vim: et sw=4
 123