//
// Copyright (C) 2007 United States Government as represented by the
// Administrator of the National Aeronautics and Space Administration
// (NASA). All Rights Reserved.
//
// This software is distributed under the NASA Open Source Agreement
// (NOSA), version 1.3. The NOSA has been approved by the Open Source
// Initiative. See the file NOSA-1.3-JPF at the top of the distribution
// directory tree for the complete NOSA document.
//
// THE SUBJECT SOFTWARE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY OF ANY
// KIND, EITHER EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING, BUT NOT
// LIMITED TO, ANY WARRANTY THAT THE SUBJECT SOFTWARE WILL CONFORM TO
// SPECIFICATIONS, ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR
// A PARTICULAR PURPOSE, OR FREEDOM FROM INFRINGEMENT, ANY WARRANTY THAT
// THE SUBJECT SOFTWARE WILL BE ERROR FREE, OR ANY WARRANTY THAT
// DOCUMENTATION, IF PROVIDED, WILL CONFORM TO THE SUBJECT SOFTWARE.
//
package java.util.concurrent.atomic;
import java.io.Serializable;
import java.util.Arrays;
/**
* model class for AtomicReferenceArray
*/
public class AtomicReferenceArray<E> implements Serializable {
private static final long serialVersionUID = -6209656149925076980L;
private final Object[] array;
public AtomicReferenceArray(int length) {
array = new Object[length];
// <2do> need a volatile write in order to conform to JMM // Does this really matter in JPF?
}
public AtomicReferenceArray(E[] array) {
if (array == null)
throw new NullPointerException();
int length = array.length;
this.array = new Object[length];
for (int i = 0; i < length; ++i)
this.array[i] = array[i];
// <2do> need a volatile write in order to conform to JMM // Does this really matter in JPF?
}
public final int length() {
return(array.length);
}
public final E get(int i) {
checkIndex(i);
return(getNative(i));
}
private final native E getNative(int i);
public final boolean compareAndSet(int i, E expect, E update) {
checkIndex(i);
return(compareAndSetNative(i, expect, update));
}
private final native boolean compareAndSetNative(int i, E expect, E update);
public final boolean weakCompareAndSet(int i, E expect, E update) {
return(compareAndSet(i, expect, update));
}
public final E getAndSet(int i, E newValue) {
while (true) {
E current = get(i);
if (compareAndSet(i, current, newValue))
return(current);
}
}
public final void set(int i, E newValue) {
getAndSet(i, newValue);
}
public final void lazySet(int i, E newValue) {
set(i, newValue);
}
public String toString() {
// <2do> need a volatile read in order to conform to JMM // Does this really matter in JPF?
return(Arrays.toString(array));
}
private void checkIndex(int i) {
if (i < 0 || i >= array.length)
throw new IndexOutOfBoundsException("index " + i);
}
}