70 lines
1.8 KiB
Java
70 lines
1.8 KiB
Java
// generics/Mixins.java
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// (c)2017 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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import java.util.*;
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interface TimeStamped { long getStamp(); }
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class TimeStampedImp implements TimeStamped {
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private final long timeStamp;
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public TimeStampedImp() {
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timeStamp = new Date().getTime();
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}
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@Override
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public long getStamp() { return timeStamp; }
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}
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interface SerialNumbered { long getSerialNumber(); }
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class SerialNumberedImp implements SerialNumbered {
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private static long counter = 1;
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private final long serialNumber = counter++;
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@Override
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public long getSerialNumber() { return serialNumber; }
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}
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interface Basic {
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void set(String val);
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String get();
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}
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class BasicImp implements Basic {
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private String value;
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@Override
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public void set(String val) { value = val; }
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@Override
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public String get() { return value; }
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}
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class Mixin extends BasicImp
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implements TimeStamped, SerialNumbered {
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private TimeStamped timeStamp = new TimeStampedImp();
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private SerialNumbered serialNumber =
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new SerialNumberedImp();
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@Override
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public long getStamp() { return timeStamp.getStamp(); }
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@Override
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public long getSerialNumber() {
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return serialNumber.getSerialNumber();
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}
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}
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public class Mixins {
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public static void main(String[] args) {
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Mixin mixin1 = new Mixin(), mixin2 = new Mixin();
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mixin1.set("test string 1");
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mixin2.set("test string 2");
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System.out.println(mixin1.get() + " " +
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mixin1.getStamp() + " " +
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mixin1.getSerialNumber());
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System.out.println(mixin2.get() + " " +
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mixin2.getStamp() + " " +
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mixin2.getSerialNumber());
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}
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}
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/* Output:
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test string 1 1469638250315 1
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test string 2 1469638250317 2
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*/
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