32 lines
924 B
Java
32 lines
924 B
Java
// generics/SelfBoundingAndCovariantArguments.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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interface
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SelfBoundSetter<T extends SelfBoundSetter<T>> {
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void set(T arg);
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}
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interface Setter extends SelfBoundSetter<Setter> {}
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public class SelfBoundingAndCovariantArguments {
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void
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testA(Setter s1, Setter s2, SelfBoundSetter sbs) {
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s1.set(s2);
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//- s1.set(sbs);
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// error: method set in interface SelfBoundSetter<T>
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// cannot be applied to given types;
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// s1.set(sbs);
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// ^
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// required: Setter
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// found: SelfBoundSetter
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// reason: argument mismatch;
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// SelfBoundSetter cannot be converted to Setter
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// where T is a type-variable:
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// T extends SelfBoundSetter<T> declared in
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// interface SelfBoundSetter
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// 1 error
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}
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}
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