37 lines
1004 B
Java
37 lines
1004 B
Java
// polymorphism/FieldAccess.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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// Direct field access is determined at compile time
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class Super {
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public int field = 0;
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public int getField() { return field; }
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}
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class Sub extends Super {
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public int field = 1;
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@Override
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public int getField() { return field; }
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public int getSuperField() { return super.field; }
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}
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public class FieldAccess {
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public static void main(String[] args) {
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Super sup = new Sub(); // Upcast
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System.out.println("sup.field = " + sup.field +
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", sup.getField() = " + sup.getField());
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Sub sub = new Sub();
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System.out.println("sub.field = " +
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sub.field + ", sub.getField() = " +
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sub.getField() +
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", sub.getSuperField() = " +
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sub.getSuperField());
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}
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}
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/* Output:
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sup.field = 0, sup.getField() = 1
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sub.field = 1, sub.getField() = 1, sub.getSuperField()
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= 0
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*/
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