Java 时区之间时间转换

 SimpleDateFormat foo = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
         System.out.println("foo:" + foo.format(new Date()));

         Calendar gc = GregorianCalendar.getInstance();
         System.out.println("gc.getTime():" + gc.getTime());
         System.out.println("gc.getTimeInMillis():" + new Date(gc.getTimeInMillis()));

         // 当前系统默认时区的时间：
         Calendar calendar = new GregorianCalendar();
         System.out.print("时区：" + calendar.getTimeZone().getID() + "  ");
         System.out.println("时间：" + calendar.get(Calendar.HOUR_OF_DAY) + ":" + calendar.get(Calendar.MINUTE));
         // 美国洛杉矶时区
         TimeZone tz = TimeZone.getTimeZone("America/Los_Angeles");
         // 时区转换
         calendar.setTimeZone(tz);
         System.out.print("时区：" + calendar.getTimeZone().getID() + "  ");
         System.out.println("时间：" + calendar.get(Calendar.HOUR_OF_DAY) + ":" + calendar.get(Calendar.MINUTE));
         Date time = new Date();

         // 1、取得本地时间：
         java.util.Calendar cal = java.util.Calendar.getInstance();

         // 2、取得时间偏移量：
         int zoneOffset = cal.get(java.util.Calendar.ZONE_OFFSET);

         // 3、取得夏令时差：
         int dstOffset = cal.get(java.util.Calendar.DST_OFFSET);

         // 4、从本地时间里扣除这些差量，即可以取得UTC时间：
         cal.add(java.util.Calendar.MILLISECOND, -(zoneOffset + dstOffset));

         // 之后调用cal.get(int x)或cal.getTimeInMillis()方法所取得的时间即是UTC标准时间。
         System.out.println("UTC:" + new Date(cal.getTimeInMillis()));

         Calendar calendar1 = Calendar.getInstance();
         TimeZone tztz = TimeZone.getTimeZone("GMT");
         calendar1.setTimeZone(tztz);
         System.out.println(calendar.getTime());
         System.out.println(calendar.getTimeInMillis());

         // SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
         // df.setTimeZone(TimeZone.getTimeZone("UTC"));
         // System.out.println(df.parse("2014-08-23T09:20:05Z").toString());

         SimpleDateFormat df1 = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
         Date t = new Date();
         System.out.println(df1.format(t));
         System.out.println(df1.format(df1.parse("2014-08-27T18:02:59.676Z")) + "***********");
         df1.setTimeZone(TimeZone.getTimeZone("UTC"));
         System.out.println(df1.format(t));
         System.out.println("-----------");
         System.out.println(df1.format(df1.parse("2014-08-27T18:02:59.676Z")) + "***********");
         System.out.println("2014-08-27T18:02:59.676Z");