35 lines
638 B
Java
35 lines
638 B
Java
//: generics/FactoryConstraint.java
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interface FactoryI<T> {
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T create();
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}
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class Foo2<T> {
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private T x;
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public <F extends FactoryI<T>> Foo2(F factory) {
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x = factory.create();
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}
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// ...
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}
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class IntegerFactory implements FactoryI<Integer> {
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public Integer create() {
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return new Integer(0);
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}
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}
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class Widget {
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public static class Factory implements FactoryI<Widget> {
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public Widget create() {
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return new Widget();
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}
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}
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}
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public class FactoryConstraint {
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public static void main(String[] args) {
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new Foo2<Integer>(new IntegerFactory());
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new Foo2<Widget>(new Widget.Factory());
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}
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} ///:~
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