1 files changed, 66 insertions, 0 deletions
diff --git a/nailgun_launcher/ClassLoaderCache.java b/nailgun_launcher/ClassLoaderCache.java
new file mode 100644
index 0000000..6bffad0
--- /dev/null
+++ b/nailgun_launcher/ClassLoaderCache.java
@@ -0,0 +1,66 @@
+package cbt;
+
+import java.util.*;
+import static java.io.File.pathSeparator;
+import static cbt.Stage0Lib.*;
+
+final public class ClassLoaderCache{
+  public Map<Object,Object> hashMap;
+  final ThreadLocal<HashSet<String>> seen = new ThreadLocal<HashSet<String>>(){
+    @Override protected HashSet<String> initialValue(){
+      return new HashSet<String>();
+    }
+  };
+
+  public ClassLoaderCache(
+    Map<Object,Object> hashMap
+  ){
+    this.hashMap = hashMap;
+  }
+
+  public ClassLoader get( String key, long timestamp ){
+    seen.get().add( key );
+    @SuppressWarnings("unchecked")
+    ClassLoader t = (ClassLoader) hashMap.get(
+      hashMap.get( key )
+    );
+    assert hashMap.get(t).equals(timestamp);
+    return t;
+  }
+
+  public boolean containsKey( String key, long timestamp ){
+    boolean contains = hashMap.containsKey( key );
+    if( contains ){
+      Object keyObject = hashMap.get( key );
+      Object classLoader = hashMap.get( keyObject );
+      long oldTimestamp = (long) hashMap.get( classLoader );
+      boolean res = oldTimestamp == timestamp;
+      return res;
+    } else {
+      return false;
+    }
+  }
+
+  public void put( String key, ClassLoader value, long timestamp ){
+    assert !seen.get().contains( key ): "Thread tries to update cache key after observing it: " + key;
+    LockableJavaKey keyObject = new LockableJavaKey();
+    hashMap.put( key, keyObject );
+    hashMap.put( keyObject, value );
+    hashMap.put( value, timestamp );
+  }
+
+  @Override public String toString(){
+    StringBuilder res = new StringBuilder();
+    res.append("ClassLoaderCache(\n\n");
+    for( Object key: hashMap.keySet() ){
+      if( key instanceof String )
+        res.append(
+          join( "\n", key.toString().split(":") ) + " -> " + hashMap.get( hashMap.get(key) )
+          + "\n\n"
+        );
+    }
+    res.append("\n\n");
+    return res.toString();
+  }
+}
+class LockableJavaKey{}