Here you can find the source of getFirstDayOfMonth(String format)
public static String getFirstDayOfMonth(String format)
//package com.java2s; /*// w w w . j a va 2 s. co m * Copyright (C) 2013 www.418log.org * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.GregorianCalendar; public class Main { public static String getFirstDayOfMonth(String format) { String strDate = null; try { Calendar c = new GregorianCalendar(); SimpleDateFormat mSimpleDateFormat = new SimpleDateFormat( format); c.set(Calendar.DAY_OF_MONTH, 1); strDate = mSimpleDateFormat.format(c.getTime()); } catch (Exception e) { e.printStackTrace(); } return strDate; } }