42 lines
982 B
Java
42 lines
982 B
Java
// polymorphism/PolyConstructors.java
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// (c)2016 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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// Constructors and polymorphism
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// don't produce what you might expect
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class Glyph {
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void draw() { System.out.println("Glyph.draw()"); }
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Glyph() {
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System.out.println("Glyph() before draw()");
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draw();
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System.out.println("Glyph() after draw()");
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}
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}
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class RoundGlyph extends Glyph {
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private int radius = 1;
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RoundGlyph(int r) {
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radius = r;
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System.out.println(
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"RoundGlyph.RoundGlyph(), radius = " + radius);
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}
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@Override
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void draw() {
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System.out.println(
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"RoundGlyph.draw(), radius = " + radius);
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}
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}
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public class PolyConstructors {
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public static void main(String[] args) {
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new RoundGlyph(5);
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}
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}
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/* Output:
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Glyph() before draw()
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RoundGlyph.draw(), radius = 0
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Glyph() after draw()
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RoundGlyph.RoundGlyph(), radius = 5
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*/
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