How to create custom HashMap ?

package swain.javainterviewhub.blogspot.in;

public class SwainHashMap {

private static int SIZE = 16;// for simplicity size is taken as 2^4
private Entry table[] = new Entry[SIZE];

/*
* User defined simple Map data structure With key and value . This is also
* used as linked list in case multiple key-value pairs lead to the same
* bucket with same hashcodes and different keys (collisions) using pointer
* 'next'
*
* @author sitansu
*/
class Entry {
final String key;
String value;
Entry next;

Entry(String k, String v) {
key = k;
value = v;
}

public String getValue() {
return value;
}

public void setValue(String value) {
this.value = value;
}

public String getKey() {
return key;
}
}

/*
* Returns the entry associated with the specified key in the HashMap .
* Returns null if the HashMap contains no mapping For the key
*/
public Entry get(String k) {
int hash = k.hashCode() % SIZE;
Entry e = table[hash];
// if bucket is found then traverse through the linked list and
// see if element is present
while (e != null) {
if (e.key.equals(k)) {
return e;
}
e = e.next;
}
return null;
}

/*
* Associates the specified value with the specified key in this map. If the
* map previously contained a mapping for the key , the old value is
* replaced.
*/
public void put(String k, String v) {
int hash = k.hashCode() % SIZE;
Entry e = table[hash];
if (e != null) {
// it means we are trying to insert duplicate
// key-value pair , hence overwrite the current
// pair with the old pair
if (e.key.equals(k)) {
e.value = v;
} else {
// traverse to the end of the list and insert new element
// in the same bucket
while (e.next != null) {
e = e.next;
}
Entry entryInOldBucket = new Entry(k, v);
e.next = entryInOldBucket;
}
} else {
// New element in the map , hence creating new bucket
Entry entryInNewBucket = new Entry(k, v);
table[hash] = entryInNewBucket;
}

}

public static void main(String[] args) {
SwainHashMap obj = new SwainHashMap();
obj.put("Niranjan", "SMTS");
obj.put("Ananth", "SSE");
obj.put("Niranjan", "SMTS1");
obj.put("Chandu", "SSE");

Entry e = obj.get("Niranjan");
System.out.println("" + e.getValue());
System.out.println(e.getValue());
}

}