How can I initialise a static Map?

Question

How would you initialise a static Map in Java?

Method one: static initialiser
Method two: instance initialiser (anonymous subclass) or some other m

Answer 1

I've read the answers and i decided to write my own map builder. Feel free to copy-paste and enjoy.

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

/**
 * A tool for easy creation of a map. Code example:

 * {@code MapBuilder.of("name", "Forrest").and("surname", "Gump").build()}
 * @param  key type (inferred by constructor)
 * @param  value type (inferred by constructor)
 * @author Vlasec (for http://stackoverflow.com/a/30345279/1977151)
 */
public class MapBuilder  {
    private Map map = new HashMap<>();

    /** Constructor that also enters the first entry. */
    private MapBuilder(K key, V value) {
        and(key, value);
    }

    /** Factory method that creates the builder and enters the first entry. */
    public static  MapBuilder mapOf(A key, B value) {
        return new MapBuilder<>(key, value);
    }

    /** Puts the key-value pair to the map and returns itself for method chaining */
    public MapBuilder and(K key, V value) {
        map.put(key, value);
        return this;
    }

    /**
     * If no reference to builder is kept and both the key and value types are immutable,
     * the resulting map is immutable.
     * @return contents of MapBuilder as an unmodifiable map.
     */
    public Map build() {
        return Collections.unmodifiableMap(map);
    }
}

EDIT: Lately, I keep finding public static method of pretty often and I kinda like it. I added it into the code and made the constructor private, thus switching to static factory method pattern.

EDIT2: Even more recently, I no longer like static method called of, as it looks pretty bad when using static imports. I renamed it to mapOf instead, making it more suitable for static imports.