20 lines
535 B
Java
20 lines
535 B
Java
// lowlevel/SynchronizedSerialNumbers.java
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// (c)2020 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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public class
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SynchronizedSerialNumbers extends SerialNumbers {
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private int serialNumber = 0;
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public synchronized int nextSerialNumber() {
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return serialNumber++;
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}
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public static void main(String[] args) {
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SerialNumberChecker.test(
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new SynchronizedSerialNumbers());
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}
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}
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/* Output:
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No duplicates detected
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*/
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