36 lines
799 B
Java
36 lines
799 B
Java
// operators/EqualsMethod.java
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// (c)2021 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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// Default equals() does not compare contents
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class ValA {
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int i;
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}
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class ValB {
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int i;
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// Works for this example, not a complete equals():
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public boolean equals(Object o) {
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ValB rval = (ValB)o; // Cast o to be a ValB
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return i == rval.i;
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}
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}
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public class EqualsMethod {
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public static void main(String[] args) {
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ValA va1 = new ValA();
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ValA va2 = new ValA();
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va1.i = va2.i = 100;
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System.out.println(va1.equals(va2));
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ValB vb1 = new ValB();
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ValB vb2 = new ValB();
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vb1.i = vb2.i = 100;
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System.out.println(vb1.equals(vb2));
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}
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}
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/* Output:
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false
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true
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*/
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