(转)SimpleDateFormat非线程安全
SimpleDateFormat非线程安全
?
package tdh.common;import java.text.SimpleDateFormat;import java.util.Date;public class Test { public static void main(String[] args) { SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd"); Date today = new Date(); Date tomorrow = new Date(today.getTime() + 1000 * 60 * 60 * 24); System.out.println(today); // 今天是2011-10-24 System.out.println(tomorrow); // 明天是2011-10-25 Thread thread1 = new Thread(new Thread1(dateFormat, today)); thread1.start(); Thread thread2 = new Thread(new Thread2(dateFormat, tomorrow)); thread2.start(); } }class Thread1 implements Runnable { private SimpleDateFormat dateFormat; private Date date; public Thread1(SimpleDateFormat dateFormat, Date date) { this.dateFormat = dateFormat; this.date = date; } public void run() { for (;;) {// 一直循环到出问题为止吧。 String strDate = dateFormat.format(date); // 如果不等于2011-10-24，证明出现线程安全问题了！！！！ if (!"2011-10-24".equals(strDate)) { System.err.println("today=" + strDate); System.exit(0); } } }}class Thread2 implements Runnable { private SimpleDateFormat dateFormat; private Date date; public Thread2(SimpleDateFormat dateFormat, Date date) { this.dateFormat = dateFormat; this.date = date; } public void run() { for (;;) { String strDate = dateFormat.format(date); // 如果不等于2011-10-25，证明出现线程安全问题了！！！！ if (!"2011-10-25".equals(strDate)) { System.err.println("tomorrow=" + strDate); System.exit(0); } } }}?
?
转载?
http://www.cnblogs.com/hyddd/articles/1643978.html
?
?