Java Reference
In-Depth Information
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// Fig. 23.8: SimpleArray.java
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// Class that manages an integer array to be shared by multiple
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// threads with synchronization.
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import
java.security.SecureRandom;
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import
java.util.Arrays;
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public class
SimpleArray
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{
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private static
final
SecureRandom generator =
new
SecureRandom();
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private final int
[] array;
// the shared integer array
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private int
writeIndex =
0
;
// index of next element to be written
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// construct a SimpleArray of a given size
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public
SimpleArray(
int
size)
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{
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array =
new
int
[size];
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}
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// add a value to the shared array
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public synchronized void
add(
int
value)
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{
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int
position = writeIndex;
// store the write index
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try
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{
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// in real applications, you shouldn't sleep while holding a lock
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Thread.sleep(generator.nextInt(
500
));
// for demo only
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}
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catch
(InterruptedException ex)
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{
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Thread.currentThread().interrupt();
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}
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// put value in the appropriate element
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array[position] = value;
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System.out.printf(
"%s wrote %2d to element %d.%n"
,
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Thread.currentThread().getName(), value, position);
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++writeIndex;
// increment index of element to be written next
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System.out.printf(
"Next write index: %d%n"
, writeIndex);
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}
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// used for outputting the contents of the shared integer array
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public
synchronized
String toString()
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{
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return
Arrays.toString(array);
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}
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}
// end class SimpleArray
Fig. 23.8
|
Class that manages an integer array to be shared by multiple threads with
synchronization. (Part 1 of 2.)
