63 lines
1.9 KiB
Java
63 lines
1.9 KiB
Java
// reflection/FamilyVsExactType.java
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// (c)2021 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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// The difference between instanceof and class
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// {java reflection.FamilyVsExactType}
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package reflection;
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class Base {}
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class Derived extends Base {}
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public class FamilyVsExactType {
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static void test(Object x) {
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System.out.println(
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"Testing x of type " + x.getClass());
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System.out.println(
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"x instanceof Base " + (x instanceof Base));
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System.out.println(
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"x instanceof Derived " + (x instanceof Derived));
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System.out.println(
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"Base.isInstance(x) " + Base.class.isInstance(x));
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System.out.println(
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"Derived.isInstance(x) " +
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Derived.class.isInstance(x));
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System.out.println(
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"x.getClass() == Base.class " +
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(x.getClass() == Base.class));
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System.out.println(
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"x.getClass() == Derived.class " +
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(x.getClass() == Derived.class));
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System.out.println(
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"x.getClass().equals(Base.class)) "+
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(x.getClass().equals(Base.class)));
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System.out.println(
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"x.getClass().equals(Derived.class)) " +
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(x.getClass().equals(Derived.class)));
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}
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public static void main(String[] args) {
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test(new Base());
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test(new Derived());
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}
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}
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/* Output:
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Testing x of type class reflection.Base
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x instanceof Base true
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x instanceof Derived false
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Base.isInstance(x) true
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Derived.isInstance(x) false
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x.getClass() == Base.class true
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x.getClass() == Derived.class false
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x.getClass().equals(Base.class)) true
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x.getClass().equals(Derived.class)) false
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Testing x of type class reflection.Derived
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x instanceof Base true
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x instanceof Derived true
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Base.isInstance(x) true
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Derived.isInstance(x) true
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x.getClass() == Base.class false
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x.getClass() == Derived.class true
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x.getClass().equals(Base.class)) false
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x.getClass().equals(Derived.class)) true
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*/
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