整理代码块

Author: enjoyCoding666

.classpath

@@ -1,13 +1,47 @@
 package com.date;
 
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
 import java.util.Calendar;
-import java.util.GregorianCalendar;
+import java.util.Date;
 
+/**
+ * @Author: EnjoyCoding
+ * @Date: 2020\5\1 0001 16:17
+ * @Description:
+ */
 public class CalendarDemo {
-    public static void main(String args[]){
-        Calendar calenda=new GregorianCalendar();   //GregorianCalendar是日历的子类。
-        System.out.println("年："+calenda.get(Calendar.YEAR));   //Calendar.YEAR是常量。意指年
 
+	public static void setCalendarTime() throws ParseException {
+		String dateStr="2018-07-07 07:08:11";
+		SimpleDateFormat simpleDateFormat=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
+		Date date = simpleDateFormat.parse(dateStr);
+		Calendar calendar = Calendar.getInstance();
+		//通过calendar设置时间
+		calendar.setTime(date);
+		//获取calendar对应的时间
+		Date time = calendar.getTime();
+		System.out.println(time);
+	}
 
-    }
+	public static void setCalendarMonthDay() {
+		Calendar calendar = Calendar.getInstance();
+		//通过Calendar设置年月日
+		calendar.set(Calendar.MONTH, 7);
+		calendar.set(Calendar.DAY_OF_MONTH, 7);
+		calendar.set(Calendar.YEAR, 2018);
+		calendar.set(Calendar.HOUR_OF_DAY,19);
+		//通过Calendar获取时间，年月日
+		Date date = calendar.getTime();
+		int year = calendar.get(Calendar.YEAR);
+		//Calendar的月份是从0开始计算的，所以要加一才是真实的月份
+		int month = calendar.get(Calendar.MONTH) + 1;
+		int day = calendar.get(Calendar.DAY_OF_MONTH);
+		int hour = calendar.get(Calendar.HOUR_OF_DAY);
+		System.out.println(date);
+		System.out.println("year:" + year);
+		System.out.println("month:" + month);
+		System.out.println("day:" + day);
+		System.out.println("hour:" + hour);
+	}
 }

.project

@@ -1,5 +1,8 @@
 package com.date;
 
+import javax.xml.crypto.Data;
+import java.text.DateFormat;
+import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 
@@ -18,4 +21,41 @@ public static void main(String args[]){
 
 
 	}
+
+	public void dateToString(Date date) {
+		SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd");
+		String str=sdf.format(date);
+		System.out.println(date+"转化为字符串是："+str);
+	}
+
+
+	public void stringToDate() {
+		//试着用SimpleDateFormat的parse方法将字符串转化为date类型
+		//MM必须大写。。区分月份和时间
+		DateFormat dateFormat=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
+		String str="2016-5-11 11:06:59";
+		Date date=null;
+		try{
+			/*Date类型的parse方法已经过时了，不可用.一般用SimpleDateFormat的parse */
+			date=dateFormat.parse(str);
+			System.out.println("今天的日期是："+date);
+		}catch(ParseException e) {
+			e.printStackTrace();
+		}
+	}
+
+	public void stringToDate2() {
+		String str="2016-07-21 15:41:52";
+		try {
+			Date date=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").parse(str);
+			System.out.println(DateFormat.getDateInstance().format(date));
+			System.out.println(new SimpleDateFormat("yyyy年MM月dd日").format(date));
+			System.out.println(new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss").format(date));
+			System.out.println(new SimpleDateFormat("yyyy/MM/dd HH/mm/ss").format(date));
+			System.out.println(new SimpleDateFormat("yyyy-MM-dd").format(date));
+		}catch(Exception e) {
+			e.printStackTrace();
+		}
+	}
+
 }

src/main/java/com/date/CalendarDemo.java

@@ -2,14 +2,14 @@
 
 public class LambdaRunnable {
     public static void main(String[] args) {
-        Runnable race2 = () -> System.out.println("Hello world !");
+        Runnable race2 = () -> System.out.println("HelloWorld world !");
         race2.run();
 
 //        传统的代码表现方式如下：
 //        Runnable race1 = new Runnable() {
 //            @Override
 //            public void run() {
-//                System.out.println("Hello world !");
+//                System.out.println("HelloWorld world !");
 //            }
 //        };
 //        race1.run