diff --git a/classpath/java/lang/Thread.java b/classpath/java/lang/Thread.java
index 53ddd25a44..20a95cad01 100644
--- a/classpath/java/lang/Thread.java
+++ b/classpath/java/lang/Thread.java
@@ -1,7 +1,11 @@
 package java.lang;
 
+import java.util.Map;
+import java.util.WeakHashMap;
+
 public class Thread implements Runnable {
   private final Runnable task;
+  private Map<ThreadLocal, Object> locals;
   private long peer;
 
   public Thread(Runnable task) {
@@ -16,6 +20,15 @@ public class Thread implements Runnable {
     }
   }
 
+  public Map<ThreadLocal, Object> locals() {
+    if (locals == null) {
+      locals = new WeakHashMap();
+    }
+    return locals;
+  }
+
+  public static native Thread currentThread();
+
   public static native void sleep(long milliseconds)
     throws InterruptedException;
 }
diff --git a/classpath/java/lang/ThreadLocal.java b/classpath/java/lang/ThreadLocal.java
new file mode 100644
index 0000000000..35003edb22
--- /dev/null
+++ b/classpath/java/lang/ThreadLocal.java
@@ -0,0 +1,36 @@
+package java.lang;
+
+import java.util.Map;
+
+public class ThreadLocal<T> {
+  private static final Object Null = new Object();
+
+  protected T initialValue() {
+    return null;
+  }
+
+  public T get() {
+    Map<ThreadLocal, Object> map = Thread.currentThread().locals();
+    Object o = map.get(this);
+    if (o == null) {
+      o = initialValue();
+      if (o == null) {
+        o = Null;
+      }
+      map.put(this, o);
+    }
+    if (o == Null) {
+      o = null;
+    }
+    return (T) o;
+  }
+
+  public void set(T value) {
+    Map<ThreadLocal, Object> map = Thread.currentThread().locals();
+    Object o = value;
+    if (o == null) {
+      o = Null;
+    }
+    map.put(this, o);
+  }
+}
diff --git a/classpath/java/lang/Throwable.java b/classpath/java/lang/Throwable.java
index f81486d93c..40db7c1d7e 100644
--- a/classpath/java/lang/Throwable.java
+++ b/classpath/java/lang/Throwable.java
@@ -23,6 +23,10 @@ public class Throwable {
     this(null, null);
   }
 
+  public Throwable getCause() {
+    return cause;
+  }
+
   private static native Object trace(int skipCount);
 
   private static native StackTraceElement[] resolveTrace(Object trace);
diff --git a/classpath/java/lang/reflect/Array.java b/classpath/java/lang/reflect/Array.java
new file mode 100644
index 0000000000..e0eae6a055
--- /dev/null
+++ b/classpath/java/lang/reflect/Array.java
@@ -0,0 +1,7 @@
+package java.lang.reflect;
+
+public final class Array {
+  private Array() { }
+
+  
+}
diff --git a/classpath/java/lang/reflect/Constructor.java b/classpath/java/lang/reflect/Constructor.java
index cba1ec9331..c6eaf2c307 100644
--- a/classpath/java/lang/reflect/Constructor.java
+++ b/classpath/java/lang/reflect/Constructor.java
@@ -1,6 +1,6 @@
 package java.lang.reflect;
 
-public class Constructor<T> extends AccessibleObject {
+public class Constructor<T> extends AccessibleObject implements Member {
   private Method<T> method;
 
   private Constructor() { }
@@ -17,4 +17,16 @@ public class Constructor<T> extends AccessibleObject {
   public void setAccessible(boolean v) {
     method.setAccessible(v);
   }
+
+  public Class<T> getDeclaringClass() {
+    return method.getDeclaringClass();
+  }
+
+  public int getModifiers() {
+    return method.getModifiers();
+  }
+
+  public String getName() {
+    return method.getName();
+  }
 }
diff --git a/classpath/java/lang/reflect/Field.java b/classpath/java/lang/reflect/Field.java
index 9fd11bf112..175f22f287 100644
--- a/classpath/java/lang/reflect/Field.java
+++ b/classpath/java/lang/reflect/Field.java
@@ -18,4 +18,16 @@ public class Field<T> extends AccessibleObject {
   public void setAccessible(boolean v) {
     if (v) vmFlags |= Accessible; else vmFlags &= ~Accessible;
   }
+
+  public Class<T> getDeclaringClass() {
+    return class_;
+  }
+
+  public int getModifiers() {
+    return flags;
+  }
+
+  public String getName() {
+    return new String(name, 0, name.length - 1, false);
+  }
 }
diff --git a/classpath/java/lang/reflect/InvocationTargetException.java b/classpath/java/lang/reflect/InvocationTargetException.java
new file mode 100644
index 0000000000..a67d5c4357
--- /dev/null
+++ b/classpath/java/lang/reflect/InvocationTargetException.java
@@ -0,0 +1,19 @@
+package java.lang.reflect;
+
+public class InvocationTargetException extends Exception {
+  public InvocationTargetException(Throwable targetException, String message) {
+    super(message, targetException);
+  }
+
+  public InvocationTargetException(Throwable targetException) {
+    this(targetException, null);
+  }
+
+  public InvocationTargetException() {
+    this(null, null);
+  }
+
+  public Throwable getTargetException() {
+    return getCause();
+  }
+}
diff --git a/classpath/java/lang/reflect/Member.java b/classpath/java/lang/reflect/Member.java
new file mode 100644
index 0000000000..2c0cd10384
--- /dev/null
+++ b/classpath/java/lang/reflect/Member.java
@@ -0,0 +1,12 @@
+package java.lang.reflect;
+
+public interface Member {
+  public static final int PUBLIC = 0;
+  public static final int DECLARED = 1;
+
+  public Class getDeclaringClass();
+
+  public int getModifiers();
+
+  public String getName();
+}
diff --git a/classpath/java/lang/reflect/Method.java b/classpath/java/lang/reflect/Method.java
index 4d18a19a0a..236138d439 100644
--- a/classpath/java/lang/reflect/Method.java
+++ b/classpath/java/lang/reflect/Method.java
@@ -1,6 +1,6 @@
 package java.lang.reflect;
 
-public class Method<T> extends AccessibleObject {
+public class Method<T> extends AccessibleObject implements Member {
   private byte vmFlags;
   private byte parameterCount;
   private short parameterFootprint;
@@ -20,4 +20,16 @@ public class Method<T> extends AccessibleObject {
   public void setAccessible(boolean v) {
     if (v) vmFlags |= Accessible; else vmFlags &= ~Accessible;
   }
+
+  public Class<T> getDeclaringClass() {
+    return class_;
+  }
+
+  public int getModifiers() {
+    return flags;
+  }
+
+  public String getName() {
+    return new String(name, 0, name.length - 1, false);
+  }
 }
diff --git a/classpath/java/lang/reflect/Modifier.java b/classpath/java/lang/reflect/Modifier.java
new file mode 100644
index 0000000000..033bf0e464
--- /dev/null
+++ b/classpath/java/lang/reflect/Modifier.java
@@ -0,0 +1,19 @@
+package java.lang.reflect;
+
+public final class Modifier {
+  public static final int PUBLIC       = 1 <<  0;
+  public static final int PRIVATE      = 1 <<  1;
+  public static final int PROTECTED    = 1 <<  2;
+  public static final int STATIC       = 1 <<  3;
+  public static final int FINAL        = 1 <<  4;
+  public static final int SUPER        = 1 <<  5;
+  public static final int SYNCHRONIZED = SUPER;
+  public static final int VOLATILE     = 1 <<  6;
+  public static final int TRANSIENT    = 1 <<  7;
+  public static final int NATIVE       = 1 <<  8;
+  public static final int INTERFACE    = 1 <<  9;
+  public static final int ABSTRACT     = 1 << 10;
+  public static final int STRICT       = 1 << 11;
+
+  private Modifier() { }
+}
diff --git a/classpath/java/util/HashMap.java b/classpath/java/util/HashMap.java
new file mode 100644
index 0000000000..5eff151671
--- /dev/null
+++ b/classpath/java/util/HashMap.java
@@ -0,0 +1,220 @@
+package java.util;
+
+public class HashMap<K, V> implements Map<K, V> {
+  private int size;
+  private Cell[] array;
+  private Cell<K, V> nullCell;
+  private final CellFactory factory;
+
+  HashMap(int capacity, CellFactory<K, V> factory) {
+    if (capacity > 0) {
+      array = new Cell[nextPowerOfTwo(capacity)];
+    }
+    this.factory = factory;
+  }
+
+  public HashMap(int capacity) {
+    this(capacity, new MyCellFactory());
+  }
+
+  public HashMap() {
+    this(0);
+  }
+
+  private static int nextPowerOfTwo(int n) {
+    int r = 1;
+    while (r < n) r <<= 1;
+    return r;
+  }
+
+  public int size() {
+    return size;
+  }
+
+  private void resize() {
+    if (array == null || size >= array.length * 2) {
+      resize(array == null ? 16 : array.length * 2);
+    } else if (size <= array.length / 3) {
+      resize(array.length / 2);
+    }
+  }
+
+  private void resize(int capacity) {
+    Cell<K, V>[] newArray = null;
+    if (capacity != 0) {
+      capacity = nextPowerOfTwo(capacity);
+      if (array != null && array.length == capacity) {
+        return;
+      }
+
+      newArray = new Cell[capacity];
+      if (array != null) {
+        for (int i = 0; i < array.length; ++i) {
+          Cell<K, V> next;
+          for (Cell<K, V> c = array[i]; c != null; c = next) {
+            next = c.next();
+            int index = c.getKey().hashCode() & (capacity - 1);
+            c.setNext(array[index]);
+            array[index] = c;
+          }
+        }
+      }
+    }
+    array = newArray;
+  }
+
+  private Cell<K, V> find(K key) {
+    if (key == null) {
+      return nullCell;
+    } else {
+      if (array != null) {
+        int index = key.hashCode() & (array.length - 1);
+        for (Cell<K, V> c = array[index]; c != null; c = c.next()) {
+          if (key.equals(c.getKey())) {
+            return c;
+          }
+        }
+      }
+
+      return null;
+    }
+  }
+
+  private void insert(Cell<K, V> cell) {
+    ++ size;
+
+    if (cell.getKey() == null) {
+      nullCell = cell;
+    } else {
+      resize();
+
+      int index = cell.hashCode() & (array.length - 1);
+      cell.setNext(array[index]);
+      array[index] = cell;
+    }
+  }
+
+  // primarily for use by WeakHashMap:
+  void remove(Cell<K, V> cell) { 
+    if (cell == nullCell) {
+      nullCell = null;
+      -- size;
+    } else {
+      int index = cell.hashCode() & (array.length - 1);
+      Cell<K, V> p = null;
+      for (Cell<K, V> c = array[index]; c != null; c = c.next()) {
+        if (c == cell) {
+          if (p == null) {
+            array[index] = c.next();
+          } else {
+            p.setNext(c.next());
+          }
+          -- size;
+          break;
+        }
+      }
+
+      resize();
+    }
+  }
+
+  public V get(K key) {
+    Cell<K, V> c = find(key);
+    return (c == null ? null : c.getValue());
+  }
+
+  public V put(K key, V value) {
+    Cell<K, V> c = find(key);
+    if (c == null) {
+      insert(factory.make(key, value, null));
+      return null;
+    } else {
+      V old = c.getValue();
+      c.setValue(value);
+      return old;
+    }
+  }
+
+  public V remove(K key) {
+    V old = null;
+    if (key == null) {
+      if (nullCell != null) {
+        old = nullCell.getValue();
+        nullCell = null;
+        -- size;
+      }
+    } else {
+      if (array != null) {
+        int index = key.hashCode() & (array.length - 1);
+        Cell<K, V> p = null;
+        for (Cell<K, V> c = array[index]; c != null; c = c.next()) {
+          if (key.equals(c.getKey())) {
+            old = c.getValue();
+            if (p == null) {
+              array[index] = c.next();
+            } else {
+              p.setNext(c.next());
+            }
+            -- size;
+            break;
+          }
+        }
+
+        resize();
+      }
+    }
+    return old;
+  }
+
+  interface Cell<K, V> extends Entry<K, V> {
+    public HashMap.Cell<K, V> next();
+
+    public void setNext(HashMap.Cell<K, V> next);
+  }
+
+  interface CellFactory<K, V> {
+    public Cell<K, V> make(K key, V value, Cell<K, V> next);
+  }
+
+  private static class MyCell<K, V> implements Cell<K, V> {
+    public final K key;
+    public V value;
+    public Cell<K, V> next;
+
+    public MyCell(K key, V value, Cell<K, V> next) {
+      this.key = key;
+      this.value = value;
+      this.next = next;
+    }
+
+    public K getKey() {
+      return key;
+    }
+
+    public V getValue() {
+      return value;
+    }
+
+    public void setValue(V value) {
+      this.value = value;
+    }
+
+    public HashMap.Cell<K, V> next() {
+      return next;
+    }
+
+    public void setNext(HashMap.Cell<K, V> next) {
+      this.next = next;
+    }
+
+    public int hashCode() {
+      return key.hashCode();
+    }
+  }
+
+  private static class MyCellFactory<K, V> implements CellFactory<K, V> {
+    public Cell<K, V> make(K key, V value, Cell<K, V> next) {
+      return new MyCell(key, value, next);
+    }
+  }
+}
diff --git a/classpath/java/util/Map.java b/classpath/java/util/Map.java
new file mode 100644
index 0000000000..2be7083a45
--- /dev/null
+++ b/classpath/java/util/Map.java
@@ -0,0 +1,19 @@
+package java.util;
+
+public interface Map<K, V> {
+  public int size();
+
+  public V get(K key);
+
+  public V put(K key, V value);
+
+  public V remove(K key);
+
+  public interface Entry<K, V> {
+    public K getKey();
+
+    public V getValue();
+
+    public void setValue(V value);
+  }
+}
diff --git a/classpath/java/util/WeakHashMap.java b/classpath/java/util/WeakHashMap.java
new file mode 100644
index 0000000000..716ab340f8
--- /dev/null
+++ b/classpath/java/util/WeakHashMap.java
@@ -0,0 +1,95 @@
+package java.util;
+
+import java.lang.ref.ReferenceQueue;
+import java.lang.ref.Reference;
+import java.lang.ref.WeakReference;
+
+public class WeakHashMap<K, V> implements Map<K, V> {
+  private final HashMap<K, V> map;
+  private final ReferenceQueue queue;
+
+  public WeakHashMap(int capacity) {
+    map = new HashMap(capacity, new MyCellFactory());
+    queue = new ReferenceQueue();
+  }
+
+  public WeakHashMap() {
+    this(0);
+  }
+
+  private void poll() {
+    for (MyCell<K, V> c = (MyCell<K, V>) queue.poll();
+         c != null;
+         c = (MyCell<K, V>) queue.poll())
+    {
+      map.remove(c);
+    }
+  }
+
+  public int size() {
+    return map.size();
+  }
+
+  public V get(K key) {
+    poll();
+    return map.get(key);
+  }
+
+  public V put(K key, V value) {
+    poll();
+    return map.put(key, value);
+  }
+
+  public V remove(K key) {
+    poll();
+    return map.remove(key);
+  }
+
+  private static class MyCell<K, V>
+    extends WeakReference<K>
+    implements HashMap.Cell<K, V>
+  {
+    public V value;
+    public HashMap.Cell<K, V> next;
+    public int hashCode;
+
+    public MyCell(K key, V value, HashMap.Cell<K, V> next) {
+      super(key);
+      this.value = value;
+      this.next = next;
+      this.hashCode = key.hashCode();
+    }
+
+    public K getKey() {
+      return get();
+    }
+
+    public V getValue() {
+      return value;
+    }
+
+    public void setValue(V value) {
+      this.value = value;
+    }
+
+    public HashMap.Cell<K, V> next() {
+      return next;
+    }
+
+    public void setNext(HashMap.Cell<K, V> next) {
+      this.next = next;
+    }
+
+    public int hashCode() {
+      return hashCode;
+    }
+  }
+
+  private static class MyCellFactory<K, V>
+    implements HashMap.CellFactory<K, V>
+  {
+    public HashMap.Cell<K, V> make(K key, V value, HashMap.Cell<K, V> next) {
+      return new MyCell(key, value, next);
+    }
+  }
+}
diff --git a/src/builtin.cpp b/src/builtin.cpp
index 5f8a9dd60d..89096d9ab9 100644
--- a/src/builtin.cpp
+++ b/src/builtin.cpp
@@ -41,6 +41,12 @@ notifyAll(Thread* t, jobject this_)
   vm::notifyAll(t, *this_);
 }
 
+jobject
+currentThread(Thread* t)
+{
+  return pushReference(t, t->javaThread);
+}
+
 void
 sleep(Thread* t, jlong milliseconds)
 {
@@ -247,6 +253,8 @@ populate(Thread* t, object map)
 
     { "Java_java_lang_Thread_start",
       reinterpret_cast<void*>(start) },
+    { "Java_java_lang_Thread_currentThread",
+      reinterpret_cast<void*>(currentThread) },
     { "Java_java_lang_Thread_sleep",
       reinterpret_cast<void*>(sleep) },
 
diff --git a/src/common.h b/src/common.h
index 76d6473a60..b7fd62dd16 100644
--- a/src/common.h
+++ b/src/common.h
@@ -1,8 +1,6 @@
 #ifndef COMMON_H
 #define COMMON_H
 
-
-
 #include "stdint.h"
 #include "stdlib.h"
 #include "stdarg.h"
@@ -29,8 +27,6 @@
 
 inline void* operator new(size_t, void* p) throw() { return p; }
 
-
-
 namespace vm {
 
 typedef void* object;
diff --git a/src/machine.cpp b/src/machine.cpp
index ed08d9151b..e5268e293b 100644
--- a/src/machine.cpp
+++ b/src/machine.cpp
@@ -1382,7 +1382,7 @@ Thread::Thread(Machine* m, Allocator* allocator, object javaThread,
 
     builtin::populate(t, m->builtinMap);
 
-    javaThread = makeThread(t, 0, reinterpret_cast<int64_t>(t));
+    javaThread = makeThread(t, 0, 0, reinterpret_cast<int64_t>(t));
   } else {
     threadPeer(this, javaThread) = reinterpret_cast<jlong>(this);
     parent->child = this;
@@ -1749,6 +1749,10 @@ hashMapResize(Thread* t, object map, uint32_t (*hash)(Thread*, object),
     PROTECT(t, oldArray);
 
     unsigned newLength = nextPowerOfTwo(size);
+    if (oldArray and arrayLength(t, oldArray) == newLength) {
+      return;
+    }
+
     newArray = makeArray(t, newLength, true);
 
     if (oldArray) {
@@ -1832,6 +1836,7 @@ hashMapRemove(Thread* t, object map, object key,
         o = tripleSecond(t, *n);
         set(t, *n, tripleThird(t, *n));
         -- hashMapSize(t, map);
+        break;
       } else {
         n = &tripleThird(t, *n);
       }
diff --git a/src/types.def b/src/types.def
index 8025a86036..cb2d124737 100644
--- a/src/types.def
+++ b/src/types.def
@@ -127,6 +127,7 @@
 (type thread java/lang/Thread
   (extends jobject)
   (object task)
+  (object locals)
   (int64_t peer))
 
 (type stackTraceElement java/lang/StackTraceElement