safestates.java

java concurrency in practice 源码. JAVA并发设计

package net.jcip.examples;

import java.util.*;

import net.jcip.annotations.*;

/**
 * SafeStates
 * <p/>
 * Initialization safety for immutable objects
 *
 * @author Brian Goetz and Tim Peierls
 */
@ThreadSafe
public class SafeStates {
    private final Map<String, String> states;

    public SafeStates() {
        states = new HashMap<String, String>();
        states.put("alaska", "AK");
        states.put("alabama", "AL");
        /*...*/
        states.put("wyoming", "WY");
    }

    public String getAbbreviation(String s) {
        return states.get(s);
    }
}