1 files changed, 316 insertions, 0 deletions
diff --git a/gcc-4.4.3/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java b/gcc-4.4.3/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java
new file mode 100644
index 000000000..102c2a7c9
--- /dev/null
+++ b/gcc-4.4.3/libjava/classpath/external/jsr166/java/util/concurrent/atomic/AtomicIntegerFieldUpdater.java
@@ -0,0 +1,316 @@
+/*
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/licenses/publicdomain
+ */
+
+package java.util.concurrent.atomic;
+import sun.misc.Unsafe;
+import java.lang.reflect.*;
+
+/**
+ * A reflection-based utility that enables atomic updates to
+ * designated <tt>volatile int</tt> fields of designated classes.
+ * This class is designed for use in atomic data structures in which
+ * several fields of the same node are independently subject to atomic
+ * updates.
+ *
+ * <p>Note that the guarantees of the {@code compareAndSet}
+ * method in this class are weaker than in other atomic classes.
+ * Because this class cannot ensure that all uses of the field
+ * are appropriate for purposes of atomic access, it can
+ * guarantee atomicity only with respect to other invocations of
+ * {@code compareAndSet} and {@code set} on the same updater.
+ *
+ * @since 1.5
+ * @author Doug Lea
+ * @param <T> The type of the object holding the updatable field
+ */
+public abstract class  AtomicIntegerFieldUpdater<T>  {
+    /**
+     * Creates and returns an updater for objects with the given field.
+     * The Class argument is needed to check that reflective types and
+     * generic types match.
+     *
+     * @param tclass the class of the objects holding the field
+     * @param fieldName the name of the field to be updated
+     * @return the updater
+     * @throws IllegalArgumentException if the field is not a
+     * volatile integer type
+     * @throws RuntimeException with a nested reflection-based
+     * exception if the class does not hold field or is the wrong type
+     */
+    public static <U> AtomicIntegerFieldUpdater<U> newUpdater(Class<U> tclass, String fieldName) {
+        return new AtomicIntegerFieldUpdaterImpl<U>(tclass, fieldName);
+    }
+
+    /**
+     * Protected do-nothing constructor for use by subclasses.
+     */
+    protected AtomicIntegerFieldUpdater() {
+    }
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful
+     * @throws ClassCastException if <tt>obj</tt> is not an instance
+     * of the class possessing the field established in the constructor
+     */
+    public abstract boolean compareAndSet(T obj, int expect, int update);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given updated value if the current value <tt>==</tt> the
+     * expected value. This method is guaranteed to be atomic with respect to
+     * other calls to <tt>compareAndSet</tt> and <tt>set</tt>, but not
+     * necessarily with respect to other changes in the field.
+     * May fail spuriously and does not provide ordering guarantees,
+     * so is only rarely an appropriate alternative to <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to conditionally set
+     * @param expect the expected value
+     * @param update the new value
+     * @return true if successful
+     * @throws ClassCastException if <tt>obj</tt> is not an instance
+     * of the class possessing the field established in the constructor
+     */
+    public abstract boolean weakCompareAndSet(T obj, int expect, int update);
+
+    /**
+     * Sets the field of the given object managed by this updater to the
+     * given updated value. This operation is guaranteed to act as a volatile
+     * store with respect to subsequent invocations of
+     * <tt>compareAndSet</tt>.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     */
+    public abstract void set(T obj, int newValue);
+
+    /**
+     * Eventually sets the field of the given object managed by this
+     * updater to the given updated value.
+     *
+     * @param obj An object whose field to set
+     * @param newValue the new value
+     * @since 1.6
+     */
+    public abstract void lazySet(T obj, int newValue);
+
+
+    /**
+     * Gets the current value held in the field of the given object managed
+     * by this updater.
+     *
+     * @param obj An object whose field to get
+     * @return the current value
+     */
+    public abstract int get(T obj);
+
+    /**
+     * Atomically sets the field of the given object managed by this updater
+     * to the given value and returns the old value.
+     *
+     * @param obj An object whose field to get and set
+     * @param newValue the new value
+     * @return the previous value
+     */
+    public int getAndSet(T obj, int newValue) {
+        for (;;) {
+            int current = get(obj);
+            if (compareAndSet(obj, current, newValue))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the previous value
+     */
+    public int getAndIncrement(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + 1;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the previous value
+     */
+    public int getAndDecrement(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current - 1;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value of the field of
+     * the given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @param delta the value to add
+     * @return the previous value
+     */
+    public int getAndAdd(T obj, int delta) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + delta;
+            if (compareAndSet(obj, current, next))
+                return current;
+        }
+    }
+
+    /**
+     * Atomically increments by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the updated value
+     */
+    public int incrementAndGet(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + 1;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically decrements by one the current value of the field of the
+     * given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @return the updated value
+     */
+    public int decrementAndGet(T obj) {
+        for (;;) {
+            int current = get(obj);
+            int next = current - 1;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Atomically adds the given value to the current value of the field of
+     * the given object managed by this updater.
+     *
+     * @param obj An object whose field to get and set
+     * @param delta the value to add
+     * @return the updated value
+     */
+    public int addAndGet(T obj, int delta) {
+        for (;;) {
+            int current = get(obj);
+            int next = current + delta;
+            if (compareAndSet(obj, current, next))
+                return next;
+        }
+    }
+
+    /**
+     * Standard hotspot implementation using intrinsics
+     */
+    private static class AtomicIntegerFieldUpdaterImpl<T> extends AtomicIntegerFieldUpdater<T> {
+        private static final Unsafe unsafe = Unsafe.getUnsafe();
+        private final long offset;
+        private final Class<T> tclass;
+        private final Class cclass;
+
+        AtomicIntegerFieldUpdaterImpl(Class<T> tclass, String fieldName) {
+            Field field = null;
+	    Class caller = null;
+	    int modifiers = 0;
+            try {
+                field = tclass.getDeclaredField(fieldName);
+		caller = sun.reflect.Reflection.getCallerClass(3);
+		modifiers = field.getModifiers();
+                sun.reflect.misc.ReflectUtil.ensureMemberAccess(
+                    caller, tclass, null, modifiers); 
+		sun.reflect.misc.ReflectUtil.checkPackageAccess(tclass);
+            } catch(Exception ex) {
+                throw new RuntimeException(ex);
+            }
+
+            Class fieldt = field.getType();
+            if (fieldt != int.class)
+                throw new IllegalArgumentException("Must be integer type");
+            
+            if (!Modifier.isVolatile(modifiers))
+                throw new IllegalArgumentException("Must be volatile type");
+         
+	    this.cclass = (Modifier.isProtected(modifiers) &&
+			   caller != tclass) ? caller : null;
+            this.tclass = tclass;
+            offset = unsafe.objectFieldOffset(field);
+        }
+
+        private void fullCheck(T obj) {
+            if (!tclass.isInstance(obj))
+                throw new ClassCastException();
+	    if (cclass != null)
+		ensureProtectedAccess(obj);
+        }
+
+        public boolean compareAndSet(T obj, int expect, int update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.compareAndSwapInt(obj, offset, expect, update);
+        }
+
+        public boolean weakCompareAndSet(T obj, int expect, int update) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.compareAndSwapInt(obj, offset, expect, update);
+        }
+
+        public void set(T obj, int newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            unsafe.putIntVolatile(obj, offset, newValue);
+        }
+
+        public void lazySet(T obj, int newValue) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            unsafe.putOrderedInt(obj, offset, newValue);
+        }
+
+        public final int get(T obj) {
+            if (obj == null || obj.getClass() != tclass || cclass != null) fullCheck(obj);
+            return unsafe.getIntVolatile(obj, offset);
+        }
+
+	private void ensureProtectedAccess(T obj) {
+	    if (cclass.isInstance(obj)) {
+		return;
+	    }
+	    throw new RuntimeException(
+                new IllegalAccessException("Class " +
+		    cclass.getName() +
+                    " can not access a protected member of class " +
+                    tclass.getName() +
+		    " using an instance of " +
+                    obj.getClass().getName()
+		)
+	    );
+	}
+    }
+}