日期格式转换

String s = "Thu Dec 24 17:33:00 GMT+08:00 2015";

SimpleDateFormat sdf=new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy",Locale.ENGLISH);

Date dd = sdf.parse(s);

SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");

System.out.println(df.format(dd));

 

这种转换要用到java.text.SimpleDateFormat类

字符串转换成日期类型：
方法1：

也是最简单的方法 Date date=new Date("2008-04-14");

方法2：

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");//小写的mm表示的是分钟
String dstr="2008-4-24";
java.util.Date date=sdf.parse(dstr);

 

日期转换成字符串：

SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
java.util.Date date=new java.util.Date();
String str=sdf.format(date);

　　

SimpleDateFormat sdf0 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss", Locale.US);
Date curDate0 = new Date();
String date0 = sdf0.format(curDate0);

SimpleDateFormat sdf1 = new SimpleDateFormat("hh:mm:ss aa", Locale.US);
String time = sdf1.format(curDate0);

SimpleDateFormat sdf2 = new SimpleDateFormat("E, MMM dd", Locale.US);
String date1 = sdf2.format(curDate0);
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy hh:mm:ss aa", Locale.US);
MessageDialog.showMessageDialog(this, "You cannot clock out within clock in 1 minute. Last clock in @ " + sdf.format(clockinTime));

// Calendar.HOUR_OF_DAY: 24    Calendar.HOUR: 12
int hourOfDay = c.get(Calendar.HOUR_OF_DAY); 

// 0:AM  1:PM
int am_pm = c.get(Calendar.AM_PM); 

int minute = c.get(Calendar.MINUTE);
String am_pm = "AM";
int hour = hourOfDay;
if (hourOfDay == 12)
    am_pm = "PM";
if (hourOfDay > 12) {
    am_pm = "PM";
    hour = hourOfDay - 12;
}
String m = Integer.toString(minute);
if (minute < 10) {
    m = "0" + m;
}
final String time = hour + ":" + m + " " + am_pm;
start_time = hourOfDay + ":" + m;
((EditText) (dialog.findViewById(R.id.editTextStart))).setText(time);
((EditText) (dialog.findViewById(R.id.editTextEnd))).setText(time);

dialog.findViewById(R.id.editTextStart).setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {

        int h = hourOfDay;
        int m = minute;
        if (m > 0 && m <= 15)
            m = 1;
        else if (m > 15 && m <= 30)
            m = 2;
        else if (m > 30 && m <= 45)
            m = 3;
        else if (m > 45) {
            m = 0;
            h = h + 1;
        }

        select_time = false;
        DurationTimePickDialog timePickerDialog = new DurationTimePickDialog(MainActivity.this, new TimePickerDialog.OnTimeSetListener()
        {
            @Override
            public void onTimeSet(TimePicker view, int hour, int minute1)
            {
                if (hour < hourOfDay || (hour == hourOfDay && minute1 < minute))
                {
                    if (select_time == false) {
                        select_time = true;
                        MessageDialog.showMessageDialog(MainActivity.this, "Start time can not be less than " + time);
                    }
                } else {
                    String m = Integer.toString(minute1);
                    if (minute1 < 10) {
                        m = "0" + m;
                    }
                    start_time = hour + ":" + m;
                    String am_pm = "AM";
                    int hour1 = hour;
                    if (hour1 == 12)
                        am_pm = "PM";
                    if (hour1 > 12) {
                        am_pm = "PM";
                        hour1 = hour - 12;
                    }
                    ((EditText) (dialog.findViewById(R.id.editTextStart))).setText(hour1 + ":" + m + " " + am_pm);
                }
            }
        }, h, m, false);
        timePickerDialog.show();
    }
});

　　

package com.baclock.ui.custom;

import android.app.TimePickerDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.os.Bundle;
import android.widget.NumberPicker;
import android.widget.TimePicker;

import java.lang.reflect.Field;

/**
 * Created by ll on 2015/10/29.
 */
public class DurationTimePickDialog extends TimePickerDialog {
    final OnTimeSetListener mCallback;
    TimePicker mTimePicker;
    private String[] strings = {"00", "15", "30", "45"};

    public DurationTimePickDialog(Context context, OnTimeSetListener callBack, int hourOfDay, int minute, boolean is24HourView) {
        super(context, callBack, hourOfDay, minute, is24HourView);
        this.mCallback = callBack;
    }

    @Override
    public void onClick(DialogInterface dialog, int which) {
        if (mCallback != null && mTimePicker != null) {
            mTimePicker.clearFocus();
            int h = mTimePicker.getCurrentHour();
            int m = mTimePicker.getCurrentMinute();
            if (m == 1)
                m = 15;
            else if (m == 2)
                m = 30;
            else if (m == 3)
                m = 45;
            mCallback.onTimeSet(mTimePicker, h, m);
        }
    }

    @Override
    protected void onStop() {
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        try {
            Class<?> rClass = Class.forName("com.android.internal.R$id");
            Field timePicker = rClass.getField("timePicker");
            this.mTimePicker = (TimePicker) findViewById(timePicker.getInt(null));
            Field m = rClass.getField("minute");

            NumberPicker mMinuteSpinner = (NumberPicker) mTimePicker.findViewById(m.getInt(null));
            mMinuteSpinner.setMinValue(0);
            mMinuteSpinner.setMaxValue(strings.length - 1);

            mMinuteSpinner.setDisplayedValues(strings);
            mMinuteSpinner.setOnLongPressUpdateInterval(100);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}