Collision in Java HashMap

Question

I am under the expression that if two key-value pairs hash to the same position, both values will be stored at the same hashcode position and no value will be overwritten. However, why is the following code giving me different result? Can anyone explain please
Thank you
Xin
import java.util.HashMap;
import java.util.Hashtable;
* @author xint
public class Main {
* @param args the command line arguments
public static void main(String[] args) {
// Test collision in HashMap
HashMap<String, String> hm = new HashMap<String,String>();
hm.put("xint", "University of Toronto");
hm.put("xint", "University of California");
System.out.println(hm.containsValue("University of Toronto"));
}

Answer 1

xerox.time wrote:
I am under the expression that if two key-value pairs hash to the same position, both values will be stored at the same hashcode position and no value will be overwritten. However, why is the following code giving me different result? Can anyone explain please Nothing will be overwritten if the keys are not equal.
Here you have two keys that not only have the same hashCode, but also are equal(). If you had two keys that had the same hashCode but were not equal, then they would hash to the same bucket, but both would be present in the map--neither would overwrite the other.
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