HashMap、SET等线程不安全类 线程安全类的写法

 

 

 

不安全	安全
StringBuilder	StringBuffer
SimpleDateFormat	jodaTime  org.joda.time.format.DateTimeFormatter;
ArrayList	public static Map map = Collections.synchronizedMap( new HashMap<>() );   public static List list = new CopyOnWriteArrayList<>();
HashMap	public static Map list = new ConcurrentHashMap<>() ; 或 public static Map list = new ConcurrentSkipListMap<>() ;
Set(HashSet、TreeSet)	public static Set list = new CopyOnWriteArraySet<>(); 或 public static Set list = new ConcurrentSkipListSet<>();