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How to use hashCode method of samples.junit4.stackoverflow.EvilHashCode class

Best Powermock code snippet using samples.junit4.stackoverflow.EvilHashCode.hashCode

Source:EvilHashCode.java

...22            return "s";23    }24	25	@Override26	public int hashCode() {27		return evilHashCode();28	}29	public int evilHashCode() {30		return 3;31	}32}...

hashCode

Using AI Code Generation

1public class TestHashCollision {2  public void testHashCollision() {3    assertEquals(0, new EvilHashCode().hashCode());4  }5}6package samples.junit4.stackoverflow;7public class EvilHashCode {8  public int hashCode() {9    return 0;10  }11}12	at org.junit.Assert.fail(Assert.java:88)13	at org.junit.Assert.failNotEquals(Assert.java:743)14	at org.junit.Assert.assertEquals(Assert.java:118)15	at org.junit.Assert.assertEquals(Assert.java:555)16	at org.junit.Assert.assertEquals(Assert.java:542)17	at samples.junit4.stackoverflow.TestHashCollision.testHashCollision(TestHashCollision.java:12)18This is not a bug in JUnit. It is a bug in the test. The test is assuming that the hashCode() method will return the same value every time it is invoked. This is not true. The hashCode() method is allowed to return a different value each time it is invoked. The only requirement is that the hashCode() method must return the same value for two objects that are equal. The test is broken because it is assuming that hashCode() must return the same value every time it is invoked. The test should be rewritten as follows:19import org.junit.Test;20import static org.junit.Assert.*;21public class TestHashCollision {22  public void testHashCollision() {23    assertEquals(0, new EvilHashCode().hashCode());24  }25}26	at org.junit.Assert.fail(Assert.java:88)27	at org.junit.Assert.failNotEquals(Assert.java:743)28	at org.junit.Assert.assertEquals(Assert.java:118)29	at org.junit.Assert.assertEquals(Assert.java:555)30	at org.junit.Assert.assertEquals(Assert.java:542)31	at samples.junit4.stackoverflow.TestHashCollision.testHashCollision(TestHashCollision.java:12)32The test is still broken. It is still assuming that hashCode() must return the same value every time it is invoked. The test should be rewritten as follows:33import org.junit.Test;34import static org.junit.Assert.*;

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