What will be the output and why

Question

Hi All,
Can anyone help me in this.
package javatests.test;
import java.util.HashMap;
import java.util.Map;
public class CopyOfHashFunction1 {
     private int hashCode;
     public static void main(String[] args) {
            Map hashTable = new HashMap();
            String key1 = new String("a");
            String key2 = new String("a");
            System.out.println(key1.hashCode());
            System.out.println(key2.hashCode());
            System.out.println(key1 == key2);
            hashTable.put(key1, 1);
            hashTable.put(key2, 2);
            System.out.println("Size = " + hashTable.size());
            System.out.println("Value when key1 is searched:"+hashTable.get(key1));
            System.out.println("Value when key2 is searched:"+hashTable.get(key2));
}Output:
97
97
false
Size = 1
Value when key1 is searched:2
Value when key2 is searched:2I feel there should be two entries in the HashTable, because when putting the second entry in the HashTable hash collision will happen and equals() method of String will be called. As the equals() method is returning false because the object references are different so HashTable should make another entry in the same bucket.
Please let me know the answer.
Thanks
Jitendra

Answer 1

Yes you are right jverd because the code in String.java is like, so it used to compare the string character by character.
854       public boolean equals(Object object) {
  855           if (object == this) {
  856               return true;
  857           }
  858           if (object instanceof String) {
  859               String s = (String) object;
  860               int hash = hashCode;  // Single read on hashCodes as they may change
  861               int shash = s.hashCode;
  862               if (count != s.count || (hash != shash && hash != 0 && shash != 0)) {
  863                   return false;
  864               }
  865               for (int i = 0; i < count; ++i) {
  866                   if (value[offset + i] != s.value[s.offset + i]) {
  867                       return false;
  868                   }
  869               }
  870               return true;
  871           }
  872           return false;
  873       }