OnJava8-Examples/typeinfo/FamilyVsExactType.java

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