SafeSimpleDateFormat.java

package com.firefly.utils.time;

import com.firefly.utils.VerifyUtils;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class SafeSimpleDateFormat {

	public static final SafeSimpleDateFormat defaultDateFormat = new SafeSimpleDateFormat();
	private ThreadLocal<SimpleDateFormat> threadLocal;

	public SafeSimpleDateFormat() {
		this("");
	}

	public SafeSimpleDateFormat(final SimpleDateFormat sdf) {
		if(sdf == null)
			throw new IllegalArgumentException("SimpleDateFormat argument is null");
		this.threadLocal = ThreadLocal.withInitial(() -> (SimpleDateFormat)sdf.clone());
	}

	public SafeSimpleDateFormat(String datePattern) {
		final String p = VerifyUtils.isEmpty(datePattern) ? "yyyy-MM-dd HH:mm:ss" : datePattern;
		this.threadLocal = ThreadLocal.withInitial(() -> new SimpleDateFormat(p));
	}

	public Date parse(String dateStr) {
		try {
			return getFormat().parse(dateStr);
		} catch (ParseException e) {
			return null;
		}
	}

	public String format(Date date) {
		return getFormat().format(date);
	}

	private DateFormat getFormat() {
		return threadLocal.get();
	}

}