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*/ |
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package jsr166e; |
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import java.io.IOException; |
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import java.io.Serializable; |
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import java.io.ObjectInputStream; |
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import java.io.ObjectOutputStream; |
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/** |
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* One or more variables that together maintain an initially zero |
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* @param x the value to add |
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*/ |
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public void add(double x) { |
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< |
Cell[] as; long b, v; HashCode hc; Cell a; int n; |
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> |
Cell[] as; long b, v; int[] hc; Cell a; int n; |
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if ((as = cells) != null || |
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!casBase(b = base, |
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Double.doubleToRawLongBits |
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(Double.longBitsToDouble(b) + x))) { |
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boolean uncontended = true; |
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int h = (hc = threadHashCode.get()).code; |
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< |
if (as == null || (n = as.length) < 1 || |
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< |
(a = as[(n - 1) & h]) == null || |
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if ((hc = threadHashCode.get()) == null || |
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> |
as == null || (n = as.length) < 1 || |
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> |
(a = as[(n - 1) & hc[0]]) == null || |
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!(uncontended = a.cas(v = a.value, |
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Double.doubleToRawLongBits |
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(Double.longBitsToDouble(v) + x)))) |
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|
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/** |
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* Returns the current sum. The returned value is <em>NOT</em> an |
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* atomic snapshot: Invocation in the absence of concurrent |
80 |
> |
* atomic snapshot; invocation in the absence of concurrent |
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* updates returns an accurate result, but concurrent updates that |
82 |
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* occur while the sum is being calculated might not be |
83 |
< |
* incorporated. Also, because double-precision arithmetic is not |
83 |
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* incorporated. Also, because floating-point arithmetic is not |
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* strictly associative, the returned result need not be identical |
85 |
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* to the value that would be obtained in a sequential series of |
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* updates to a single variable. |
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s.writeDouble(sum()); |
188 |
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} |
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|
190 |
< |
private void readObject(ObjectInputStream s) |
191 |
< |
throws IOException, ClassNotFoundException { |
190 |
> |
private void readObject(java.io.ObjectInputStream s) |
191 |
> |
throws java.io.IOException, ClassNotFoundException { |
192 |
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s.defaultReadObject(); |
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busy = 0; |
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cells = null; |