//Spring TransactionSynchronizationManager類
@Override
protected void doBegin(Object transaction, TransactionDefinition definition) {
  DataSourceTransactionObject txObject = (DataSourceTransactionObject) transaction;
  Connection con = null;
  try {
    //此處省略N行代碼
    if (txObject.isNewConnectionHolder()) {
      //綁定數(shù)據(jù)庫連接到線程中
TransactionSynchronizationManager.bindResource(obtainDataSource(), txObject.getConnectionHolder());
    }
  }
  catch (Throwable ex) {
    if (txObject.isNewConnectionHolder()) {
      //當發(fā)生異常時，移除線程中的連接
      DataSourceUtils.releaseConnection(con, obtainDataSource());
      txObject.setConnectionHolder(null, false);
    }
    throw new CannotCreateTransactionException("Could not open JDBC Connection for transaction", ex);
  }
}

private static final ThreadLocal<LoginUser> loginUserLocal = new ThreadLocal<LoginUser>();
public static LoginUser getLoginUser() {
  return loginUserLocal.get();
}
public static void setLoginUser(LoginUser loginUser) {
  loginUserLocal.set(loginUser);
}
public static void clear() {
  loginUserLocal.remove();
}
//在使用完后一定要清理防止內(nèi)存泄露
try{
  loginUserLocal.set(loginUser);
  //執(zhí)行其他業(yè)務邏輯
}finally{
  loginUserLocal.remove();
}

/**
 * 日期工具類(使用了ThreadLocal獲取SimpleDateFormat,其他方法可以直接拷貝common-lang)
 * @author Niu Li
 * @date 2016/11/19
 */
public class DateUtil {

 private static Map<String,ThreadLocal<SimpleDateFormat>> sdfMap = new HashMap<String, ThreadLocal<SimpleDateFormat>>();

 private static Logger logger = LoggerFactory.getLogger(DateUtil.class);

 public final static String MDHMSS = "MMddHHmmssSSS";
 public final static String YMDHMS = "yyyyMMddHHmmss";
 public final static String YMDHMS_ = "yyyy-MM-dd HH:mm:ss";
 public final static String YMD = "yyyyMMdd";
 public final static String YMD_ = "yyyy-MM-dd";
 public final static String HMS = "HHmmss";

 /**
  * 根據(jù)map中的key得到對應線程的sdf實例
  * @param pattern map中的key
  * @return 該實例
  */
 private static SimpleDateFormat getSdf(final String pattern){
  ThreadLocal<SimpleDateFormat> sdfThread = sdfMap.get(pattern);
  if (sdfThread == null){
   //雙重檢驗,防止sdfMap被多次put進去值,和雙重鎖單例原因是一樣的
   synchronized (DateUtil.class){
    sdfThread = sdfMap.get(pattern);
    if (sdfThread == null){
     logger.debug("put new sdf of pattern " + pattern + " to map");
     sdfThread = new ThreadLocal<SimpleDateFormat>(){
      @Override
      protected SimpleDateFormat initialValue() {
       logger.debug("thread: " + Thread.currentThread() + " init pattern: " + pattern);
       return new SimpleDateFormat(pattern);
      }
     };
     sdfMap.put(pattern,sdfThread);
    }
   }
  }
  return sdfThread.get();
 }

 /**
  * 按照指定pattern解析日期
  * @param date 要解析的date
  * @param pattern 指定格式
  * @return 解析后date實例
  */
 public static Date parseDate(String date,String pattern){
  if(date == null) {
   throw new IllegalArgumentException("The date must not be null");
  }
  try {
   return getSdf(pattern).parse(date);
  } catch (ParseException e) {
   e.printStackTrace();
   logger.error("解析的格式不支持:"+pattern);
  }
  return null;
 }
 /**
  * 按照指定pattern格式化日期
  * @param date 要格式化的date
  * @param pattern 指定格式
  * @return 解析后格式
  */
 public static String formatDate(Date date,String pattern){
  if (date == null){
   throw new IllegalArgumentException("The date must not be null");
  }else {
   return getSdf(pattern).format(date);
  }
 }
}