29 lines
775 B
Java
29 lines
775 B
Java
// generics/ErasureAndInheritance.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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class GenericBase<T> {
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private T element;
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public void set(T arg) { element = arg; }
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public T get() { return element; }
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}
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class Derived1<T> extends GenericBase<T> {}
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class Derived2 extends GenericBase {} // No warning
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// class Derived3 extends GenericBase<?> {}
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// Strange error:
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// unexpected type
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// required: class or interface without bounds
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public class ErasureAndInheritance {
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@SuppressWarnings("unchecked")
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public static void main(String[] args) {
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Derived2 d2 = new Derived2();
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Object obj = d2.get();
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d2.set(obj); // Warning here!
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}
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}
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