Using the Collections.synchronized methods : Collections « Collections « Java Tutorial

1. Java Tutorial
2. Collections
3. Collections

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class MainClass {
  public static void main(String[] args) {
    Collection c = Collections.synchronizedCollection(new ArrayList());
    List list = Collections.synchronizedList(new ArrayList());
    Set s = Collections.synchronizedSet(new HashSet());
    Map m = Collections.synchronizedMap(new HashMap());
  }
}