asMap-implementation for Java (based on Arrays.asList)

I am always tired of the very verbose syntax in Java for creating small maps. Arrays.asList(T... a) is very convenient, and therefore I want something similar for a map.

public class MapUtils {
    public static  MapBuilder asMap(K key, V value) {
        return new MapBuilder().entry(key, value);
    }

    public static class MapBuilder extends HashMap {
        public MapBuilder entry(K key, V value) {
            this.put(key, value);
            return this;
        }
    }
}

/* Example of how to use asMap */
public class Example {
    public void example() {
        Map map = MapUtil.asMap("key", "value").entry("key2", "value2");
    }
}

/* Example of how the one way to create an inline Map in Java */
public class Before {
    public void before() {
        Map map = new HashMap() {{
            put("key", value");
            put("key2", value2");
        }};
    }
}

Any inputs on how to improve this implementation of MapUtils? Do you consider the asMap function a good idea, or am I too lazy to write some extra characters?

In my opinion MapBuilder should contain a Map, not extend one. Another possible design would be to use a single call with varargs:

public class MapUtil {
    public static  Map asMap(Map.Entry... entries) {
        Map map = new HashMap();
        for(Map.Entry entry : entries) {
            map.put(entry.getKey(), entry.getValue());
        }
        return map;
    }

    public static  Map.Entry e(final K k, final V v) {
        return new Map.Entry() {
            public K getKey() {
                return k;
            }
            public V getValue() {
                return v;
            }
            public V setValue(V value) {
                throw new UnsupportedOperationException("Not supported");
            }
        };
    }
} 

import static very.useful.MapUtil.*;
... 
Map map = asMap(e("x",1),e("y",2),e("z",3));

StackExchange Code Review Q#3245, answer score: 8