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private UtilityClass() {
throw new AssertionError();
}
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import java.util.Date;
import java.text.SimpleDateFormat; //ΪÁËÏÔʾʱ¼ä¶ø¼Ó
Date date = new Date(); //»ñµÃϵͳʱ¼ä.
String nowTime = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(date);
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