DiamondInheritance.java

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/*
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 *
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 * modification, are permitted provided that the following conditions
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 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
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 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
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public class DiamondInheritance {
 
    public interface Animal {
 
        String go();
    }
 
    public interface Horse extends Animal {
 
        @Override
        default String go() {
            return this.getClass().getSimpleName() + " walks on four legs";
        }
    }
 
    public interface Bird extends Animal {
 
        @Override
        default String go() {
            return this.getClass().getSimpleName() + " walks on two legs";
        }
 
        default String fly() {
            return "I can fly";
        }
    }
 
    public static class Pegasus implements Horse, Bird {
 
        @Override
        public String go() {
            return Horse.super.go();
        }
    }
 
    public static void main(final String[] args) {
        System.out.println(new Pegasus().go());
    }
}