javase

.idea/compiler.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <annotationProcessing>
+      <profile default="true" name="Default" enabled="true" />
+    </annotationProcessing>
+  </component>
+</project>

day11/day11.iml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

day11/src/com/four/day11/duotai01/Demo.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public class Demo {
+}

day11/src/com/four/day11/duotai01/Demo1.java

@@ -0,0 +1,26 @@
+package com.four.day11.duotai01;
+
+public class Demo {
+
+    public static void main(String[] args) {
+        //声明父类 | 接口类型
+        //new 子类的类型。
+//        Person person = new Student();
+//        person.name = "zs";
+//        person.show();
+
+        System.out.println("-------------------------");
+        //instanceof 检查类型
+//        if ( person instanceof Person ){
+//            System.out.println("属于Person类型");
+//        }
+//
+//        if ( person instanceof Student ){
+//            System.out.println("属于Student类型");
+//        }
+
+
+
+    }
+
+}

day11/src/com/four/day11/duotai01/Demo2.java

@@ -0,0 +1,20 @@
+package com.four.day11.duotai01;
+
+public class Demo1 {
+
+    public static void main(String[] args) {
+        //声明父类 | 接口类型
+        //new 子类的类型。
+
+        Employee e1 = new Student();
+        Employee e2 = new Teacher();
+
+        //相同的方法
+        e1.eat();
+        e2.eat();
+
+        //通用性。
+
+    }
+
+}

day11/src/com/four/day11/duotai01/Demo3.java

@@ -0,0 +1,30 @@
+package com.four.day11.duotai01;
+
+public class Demo2 {
+
+    public static void main(String[] args) {
+        //声明父类 | 接口类型
+        //new 子类的类型。
+
+
+        //学生 类型
+        // Student类型
+        // Employee类型
+        // FlyingInterface类型
+        // Object类型
+
+        FlyingInterface f1 = new Student();
+        FlyingInterface f2 = new Teacher();
+
+        f1.flying();
+        f2.flying();
+
+
+//        Student s = new Student();
+//        if ( s instanceof Student) {
+//            System.out.println("学生类型");
+//        }
+
+    }
+
+}

day11/src/com/four/day11/duotai01/Employee.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public class Employee {
+}

day11/src/com/four/day11/duotai01/FlyingInterface.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public interface FlyingInterface {
+}

day11/src/com/four/day11/duotai01/Man.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public class Man {
+}

day11/src/com/four/day11/duotai01/Person.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public class Person {
+}

day11/src/com/four/day11/duotai01/Student.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public class Student {
+}

day11/src/com/four/day11/duotai01/Teacher.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai01;public class Teacher {
+}

day11/src/com/four/day11/duotai02/Animal.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai02;public class Animal {
+}

day11/src/com/four/day11/duotai02/Chicken.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai02;public class Chicken {
+}

day11/src/com/four/day11/duotai02/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai02;public class Demo01 {
+}

day11/src/com/four/day11/duotai02/Dog.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai02;public class Dog {
+}

day11/src/com/four/day11/duotai02/PrintUtils.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai02;public class PrintUtils {
+}

day11/src/com/four/day11/duotai03/Animal.java

@@ -0,0 +1,15 @@
+package com.four.day11.duotai02;
+
+public class Animal {
+
+    //多态和属性 没有关系。
+
+    public void jump(){
+
+    }
+
+    public void sing(){
+
+    }
+
+}

day11/src/com/four/day11/duotai03/Cat.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai03;public class Cat {
+}

day11/src/com/four/day11/duotai03/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai03;public class Demo01 {
+}

day11/src/com/four/day11/duotai03/Demo02.java

@@ -0,0 +1,18 @@
+package com.four.day11.duotai03;
+
+public class Demo02 {
+
+
+    public static void main(String[] args) throws CloneNotSupportedException {
+
+        Person person = new Person();
+
+        Object clone = person.clone();
+        System.out.println(clone);
+
+        Student student = new Student();
+        Object clone1 = student.clone();
+        System.out.println(clone1);
+
+    }
+}

day11/src/com/four/day11/duotai03/Dog.java

@@ -0,0 +1,14 @@
+package com.four.day11.duotai02;
+
+public class Dog extends Animal {
+
+    @Override
+    public void jump() {
+        System.out.println("Dog jump ");
+    }
+
+    @Override
+    public void sing() {
+        System.out.println("Dog sing ");
+    }
+}

day11/src/com/four/day11/duotai03/FactoryAniaml.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai03;public class FactoryAniaml {
+}

day11/src/com/four/day11/duotai03/Person.java

@@ -0,0 +1,4 @@
+package com.four.day11.duotai03;
+
+public class Person {
+}

day11/src/com/four/day11/duotai03/Student.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai03;public class Student {
+}

day11/src/com/four/day11/duotai04/AreaInterface.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai04;public class AreaInterface {
+}

day11/src/com/four/day11/duotai04/Circle.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai04;public class Circle {
+}

day11/src/com/four/day11/duotai04/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai04;public class Demo01 {
+}

day11/src/com/four/day11/duotai04/Rectangle.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai04;public class Rectangle {
+}

day11/src/com/four/day11/duotai04/Shape.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai04;public class Shape {
+}

day11/src/com/four/day11/duotai04/Triangle.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai04;public class Triangle {
+}

day11/src/com/four/day11/duotai05/Animal.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai05;public class Animal {
+}

day11/src/com/four/day11/duotai05/Cat.java

@@ -0,0 +1,13 @@
+package com.four.day11.duotai05;
+
+public class Dog extends Animal{
+    @Override
+    public void eat() {
+        System.out.println("Dog eat ");
+    }
+
+    public void sleep() {
+        System.out.println("Dog sleep ");
+    }
+
+}

day11/src/com/four/day11/duotai05/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai05;public class Demo01 {
+}

day11/src/com/four/day11/duotai05/Dog.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai05;public class Dog {
+}

day11/src/com/four/day11/duotai06/Demo.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai06;public class Demo {
+}

day11/src/com/four/day11/duotai06/MyClass.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai06;public class MyClass {
+}

day11/src/com/four/day11/duotai07/Fu.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai07;public class Fu {
+}

day11/src/com/four/day11/duotai07/TestZi.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai07;public class TestZi {
+}

day11/src/com/four/day11/duotai07/Zi.java

@@ -0,0 +1,2 @@
+package com.four.day11.duotai07;public class Zi {
+}

day12/day12.iml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

day12/src/com/four/day12/demo01/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo01;public class Demo01 {
+}

day12/src/com/four/day12/demo01/Demo02.java

@@ -0,0 +1,30 @@
+package com.four.day12.demo01;
+
+import java.io.FileNotFoundException;
+
+public class Demo02 {
+
+    public static void main(String[] args) throws FileNotFoundException {
+        //编译异常
+        //可能出现问题。
+
+        //文件
+        //FileInputStream fis = new FileInputStream("a.txt");
+        //FileNotFoundException
+        //运行期异常
+
+        //空指针
+        int[] arr = new int[10];
+        //arr = null;
+        // 不能将空 null 当作对象使用。
+        // NullPointerException
+        if ( arr != null ){
+            System.out.println(arr.length);
+        }
+        //System.out.println(arr.length);
+        //数组越界
+
+        //arr[11] = 1; ArrayIndexOutOfBoundsException
+
+    }
+}

day12/src/com/four/day12/demo02/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo02;public class Demo01 {
+}

day12/src/com/four/day12/demo02/Demo02.java

@@ -0,0 +1,35 @@
+package com.four.day12.demo02;
+
+public class Demo01 {
+
+
+    public static void main(String[] args) {
+        //除0异常
+        //try 尝试处理问题。没有问题 正常执行。
+        //catch try出现问题，叫给 catch处理
+        //处理类型 范围
+
+        try {
+            System.out.println("运算");
+            int i = 1 / 0;
+
+        }catch ( Exception e ){
+            //处理 警告
+            //e.printStackTrace();
+            //不处理
+            //输出提示
+            //System.out.println(e.getMessage());
+            //程序停止 警告
+            //System.exit(0); //程序退出
+
+            //抛出异常
+            throw new ArithmeticException("/ by zero 0不能当作被除数。");
+        }
+
+        System.out.println("程序执行");
+
+
+    }
+
+
+}

day12/src/com/four/day12/demo02/Demo03.java

@@ -0,0 +1,21 @@
+package com.four.day12.demo02;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+
+public class Demo02 {
+
+
+    public static void main(String[] args) {
+
+        try {
+            FileInputStream fis = new FileInputStream("a.txt");
+        } catch (FileNotFoundException e) {
+
+            throw new RuntimeException(e);
+        }
+
+    }
+
+
+}

day12/src/com/four/day12/demo02/Demo04.java

@@ -0,0 +1,37 @@
+package com.four.day12.demo02;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+
+public class Demo03 {
+
+
+    public static void main(String[] args) {
+
+        //
+
+        try {
+            //int i= 1/0;  // ArithmeticException
+
+            //String s = null;  //NullPointerException
+            //s.equals("1");
+
+            int[] arr= new int[1];
+            arr[1] = 0;
+
+        }
+//        catch (ArithmeticException e1){
+//            e1.printStackTrace();
+//        }catch ( NullPointerException e2 ){
+//            e2.printStackTrace();
+//        }
+        catch (RuntimeException e3){
+            //范围
+            e3.printStackTrace();
+        }
+
+
+    }
+
+
+}

day12/src/com/four/day12/demo02/Demo05.java

@@ -0,0 +1,33 @@
+package com.four.day12.demo02;
+
+public class Demo04 {
+
+
+    public static void main(String[] args) {
+
+        //
+
+        try {
+            //int i= 1/0;  // ArithmeticException
+
+            //String s = null;  //NullPointerException
+            //s.equals("1");
+
+            int[] arr= new int[1];
+            arr[1] = 0;
+
+        } catch (RuntimeException e3){
+            //范围
+            //e3.printStackTrace();
+            throw new ArrayIndexOutOfBoundsException("数组越界");
+
+        } finally {
+            System.out.println("程序一定要执行的");
+        }
+
+        System.out.println("后面代码");
+
+    }
+
+
+}

day12/src/com/four/day12/demo03/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo03;public class Demo01 {
+}

day12/src/com/four/day12/demo03/Person.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo03;public class Person {
+}

day12/src/com/four/day12/demo04/AClass.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo04;public class AClass {
+}

day12/src/com/four/day12/demo04/BClass.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo04;public class BClass {
+}

day12/src/com/four/day12/demo04/CClass.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo04;public class CClass {
+}

day12/src/com/four/day12/demo05/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo05;public class Demo01 {
+}

day12/src/com/four/day12/demo06/Deom01.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo06;public class Deom01 {
+}

day12/src/com/four/day12/demo06/Deom02.java

@@ -0,0 +1,33 @@
+package com.four.day12.demo06;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+//类名不能是Test
+public class Deom01 {
+    //Alt + 回车 + 选择 junit4.13.1 导入
+    //junit 就是jar包。
+    //原理 通过对 有 @Test 注解的代码的横切。
+    @Test
+    public void test01(){
+        System.out.println("hello world1");
+    }
+
+    @Test
+    public void test02(){
+        System.out.println("hello world2");
+    }
+
+    @Before
+    public void before(){
+        System.out.println("before");
+    }
+
+
+    @After
+    public void after(){
+        System.out.println("after");
+    }
+
+}

day12/src/com/four/day12/demo06/Person.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo06;public class Person {
+}

day12/src/com/four/day12/demo07/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo07;public class Demo01 {
+}

day12/src/com/four/day12/demo07/Demo02.java

@@ -0,0 +1,25 @@
+package com.four.day12.demo07;
+
+import org.junit.Test;
+
+public class Demo01 {
+
+
+    @Test
+    public void test() {
+
+
+        //调用api
+        Integer age = 20;
+        age.hashCode();
+        int i1 = age.compareTo(20);
+        System.out.println(i1);
+
+        //int
+        int i = 10;
+
+
+
+    }
+
+}

day12/src/com/four/day12/demo07/Demo03.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo07;public class Demo03 {
+}

day12/src/com/four/day12/demo07/Demo04.java

@@ -0,0 +1,4 @@
+package com.four.day12.demo07;
+
+public class Demo04 {
+}

day12/src/com/four/day12/demo07/TestChange.java

@@ -0,0 +1,2 @@
+package com.four.day12.demo07;public class TestChange {
+}

day13/day13.iml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

day13/src/com/four/day13/demo01/Demo01.java

@@ -0,0 +1,60 @@
+package com.four.day13;
+
+public class Demo01 {
+
+    public static void main(String[] args) {
+
+
+        /*
+        - double Math.PI：圆周率
+        - double Math.random()：返回[0,1 ) 范围的小数
+        - double Math.sqrt(参数x)：返回x的平方根
+        - 基本数据类型 Math.abs(参数x)：返回x的绝对值，这个方法有重载形式，支持多种参数类型。
+        - double Math.ceil(x)：对x向上取整
+        - double Math.floor(x)：对x向下取整
+        - double Math.round(x)：类似于四舍五入
+        - double Math.pow(x, y)：求x的y次方，x,y可以是整数可以是小数
+        - double Math.max(x,y)：求x,y的最大值
+        - double Math.min(x,y)：求x,y的最小值
+         */
+
+        double pi = Math.PI;
+        System.out.println(pi);
+
+        double random = Math.random();
+        System.out.println(random);
+
+        double sqrt = Math.sqrt(4);
+        System.out.println(sqrt);
+
+        int abs = Math.abs(-1);
+        System.out.println(abs);
+        int abs1 = Math.abs(1);
+        System.out.println(abs1);
+
+        double floor = Math.floor(4.3);
+        System.out.println(floor);
+
+        double floor1 = Math.floor(-4.3);
+        System.out.println(floor1);
+
+        double ceil = Math.ceil(4.1);
+        System.out.println(ceil);
+
+        long round = Math.round(4.4);
+        System.out.println(round);
+
+        long round1 = Math.round(4.6);
+        System.out.println(round1);
+
+        double pow = Math.pow(3, 3);
+        System.out.println(pow);
+
+        int min = Math.min(11, 10);
+        System.out.println(min);
+
+
+
+
+    }
+}

day13/src/com/four/day13/demo01/Demo02.java

@@ -0,0 +1,41 @@
+package com.four.day13;
+
+import java.math.BigDecimal;
+
+public class Demo02 {
+
+    public static void main(String[] args) {
+
+
+        //0.0000000000000000000000000000000000002
+        //0.000000000000000000000000000000000000000000000000000000000003
+        BigDecimal d1 = new BigDecimal("0.00000000000000002");
+        BigDecimal d2 = new BigDecimal("0.00000000000000000000000000003");
+
+        //加减乘除
+        BigDecimal add = d1.add(d2);
+        System.out.println("add："+add);
+
+        BigDecimal sub = d1.subtract(d2);
+        System.out.println("sub:"+sub);
+
+        BigDecimal mul = d1.multiply(d2);
+        System.out.println("mul:"+mul);
+
+//        BigDecimal div = d1.divide(d2);
+//        System.out.println(div);
+
+        /*
+            除数的值
+            保留位数
+            模式
+         */
+        BigDecimal divide = d1.divide(d2, 1000, BigDecimal.ROUND_HALF_UP);
+        System.out.println(divide);
+
+
+
+
+    }
+
+}

day13/src/com/four/day13/demo01/Demo03.java

@@ -0,0 +1,29 @@
+package com.four.day13;
+
+import java.math.BigDecimal;
+import java.math.BigInteger;
+
+public class Demo03 {
+
+    public static void main(String[] args) {
+
+
+        BigInteger i1 = new BigInteger("300000000000000000000000000009");
+        BigInteger i2 = new BigInteger("100000000000000000000000000000");
+
+
+        BigInteger i3 = i1.add(i2);
+        System.out.println(i3);
+
+
+        BigInteger divide = i1.divide(i2);
+        System.out.println(divide);
+
+
+        BigInteger i4 = new BigInteger("40");
+        BigDecimal i5 = new BigDecimal(i4);
+
+        
+    }
+
+}

day13/src/com/four/day13/demo02/Demo.java

@@ -0,0 +1,2 @@
+package com.four.day13.demo02;public class Demo {
+}

day13/src/com/four/day13/demo02/Demo1.java

@@ -0,0 +1,72 @@
+package com.four.day13.demo02;
+
+import org.junit.Test;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Date;
+
+public class Demo {
+
+
+    @Test
+    public void test01(){
+        //Date
+        Date date = new Date();
+        System.out.println("date:"+date);
+
+        //1970 到现在 毫秒值
+        long time = date.getTime();
+        System.out.println("time:"+time);
+
+        long l1 = time - 3600 * 1000;
+        //传入毫秒值 返回日期
+        Date date1 = new Date(l1);
+        System.out.println(date1);
+
+        //时间戳
+        long l = System.currentTimeMillis();
+        System.out.println(l);
+
+
+    }
+
+
+    @Test
+    public void test02(){
+
+        Date date = new Date();
+
+        int year = date.getYear();
+        System.out.println(year);
+
+        int month = date.getMonth();
+        System.out.println(month);
+
+        Date date1 = new Date(125, 7, 20);
+        System.out.println(date1);
+
+
+    }
+
+
+    @Test
+    public void test03() throws ParseException {
+        //转换  日期和字符串
+
+        //日期 ->字符串  格式 yyyy-MM-dd HH:mm:ss
+        Date date = new Date();
+        //格式
+        SimpleDateFormat sdf = new SimpleDateFormat("MM-dd-yyyy HH:mm:ss");
+        //转换 format
+        String format = sdf.format(date);
+        System.out.println(format);
+
+        //字符串 > 日期 格式 yyyy-MM-dd HH:mm:ss
+
+        String d = "07-31-2025 11:02:53";
+        //转换
+        Date parse = sdf.parse(d);
+        System.out.println(parse);
+    }
+}

day13/src/com/four/day13/demo02/Demo2.java

@@ -0,0 +1,65 @@
+package com.four.day13.demo02;
+
+import org.junit.Test;
+
+import java.text.ParseException;
+import java.text.SimpleDateFormat;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.TimeZone;
+
+public class Demo1 {
+
+
+    @Test
+    public void test01() {
+
+        Calendar instance = Calendar.getInstance();
+        //设置时间
+        instance.setTime(new Date());
+
+        System.out.println(instance.getTime());
+
+        //操作年月日
+        instance.set(Calendar.MONTH, 11);
+        instance.set(Calendar.YEAR, 2025);
+        instance.set(Calendar.DAY_OF_MONTH, 15);
+
+        System.out.println(instance.getTime());
+
+
+
+        Calendar instance1 = Calendar.getInstance();
+        //设置时间
+        instance1.setTime(new Date());
+        int i1 = instance1.get(Calendar.MONTH);
+        System.out.println("month:"+i1);
+
+        int i2 = instance1.get(Calendar.DAY_OF_MONTH);
+        System.out.println("day:"+i2);
+
+
+        //将月份 + 1;
+        instance1.set(Calendar.MONTH,i1+1);
+        int i3 = instance1.get(Calendar.MONTH);
+        System.out.println("month:"+i3);
+
+        int i11 = instance1.get(Calendar.DAY_OF_MONTH);
+
+        //天数加 + 10;
+        instance1.set(Calendar.DAY_OF_MONTH,i11-10);
+
+        System.out.println(instance1.getTime());
+
+    }
+
+
+    @Test
+    public void test02() {
+        String[] availableIDs = TimeZone.getAvailableIDs();
+
+        for (int i1 = 0; i1 < availableIDs.length; i1++) {
+            System.out.println(availableIDs[i1]);
+        }
+    }
+}

day13/src/com/four/day13/demo02/Demo3.java

@@ -0,0 +1,92 @@
+package com.four.day13.demo02;
+
+import org.junit.Test;
+
+import java.time.LocalDate;
+import java.time.LocalDateTime;
+import java.time.LocalTime;
+import java.time.Month;
+import java.time.temporal.ChronoField;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.Locale;
+import java.util.TimeZone;
+
+public class Demo2 {
+
+
+    @Test
+    public void test01() {
+
+        //本地时间
+        LocalTime localTime = LocalTime.now();
+        System.out.println(localTime);
+
+        LocalDate localDate = LocalDate.now();
+        System.out.println(localDate);
+
+        LocalDateTime localDateTime = LocalDateTime.now();
+        System.out.println(localDateTime);
+    }
+
+    @Test
+    public void test02() {
+
+        //设置
+        LocalDate localDate = LocalDate.of(2025, 7, 31);
+        System.out.println(localDate);
+
+        // get 获取
+        int i1 = localDate.get(ChronoField.YEAR);
+        System.out.println("年份："+i1);
+
+        int year = localDate.getYear();
+        System.out.println("年份："+year);
+
+        Month month = localDate.getMonth();
+        System.out.println(month);
+
+        int monthValue = localDate.getMonthValue();
+        System.out.println(monthValue);
+
+        //with 设置
+        LocalDate localDate1 = localDate.withYear(2026);
+        System.out.println(localDate1);
+
+        //plus 加
+        LocalDate localDate2 = localDate1.plusYears(1);
+        System.out.println(localDate2);
+        //minus 减
+
+        LocalDate localDate3 = localDate2.minusMonths(12);
+        System.out.println(localDate3);
+
+
+    }
+
+    @Test
+    public void test03() {
+
+        LocalDate localDate1 = LocalDate.of(2025, 7, 31);
+        LocalDate localDate2 = LocalDate.of(2025, 7, 30);
+
+        boolean before = localDate1.isBefore(localDate2);
+        System.out.println(before);
+
+        boolean after = localDate1.isAfter(localDate2);
+        System.out.println(after);
+
+        boolean leapYear = localDate1.isLeapYear();
+        System.out.println(leapYear);
+
+        //11010100101001010
+        //000000000000000011
+
+        int dayOfYear = localDate1.getDayOfYear();
+        System.out.println(dayOfYear);
+
+        LocalDate localDate = localDate2.plusYears(10);
+        System.out.println(localDate);
+    }
+
+}

day13/src/com/four/day13/demo02/Demo4.java

@@ -0,0 +1,71 @@
+package com.four.day13.demo02;
+
+import org.junit.Test;
+
+import java.time.*;
+import java.time.temporal.ChronoField;
+import java.time.temporal.ChronoUnit;
+
+public class Demo3 {
+
+
+    @Test
+    public void test01() {
+
+        //日期
+        LocalDate localDate1 = LocalDate.now();
+        LocalDate localDate2 = LocalDate.of(2021,1,1);
+
+        Period between = Period.between(localDate2, localDate1);
+        System.out.println(between.getDays());
+        System.out.println(between.getYears());
+        System.out.println(between.getMonths());
+
+        System.out.println(between);
+
+
+    }
+
+    @Test
+    public void test02() {
+
+        LocalTime localTime1 = LocalTime.now();
+        LocalTime localTime2 = LocalTime.of(10, 20, 30);
+
+
+        Duration between = Duration.between(localTime1, localTime2);
+        System.out.println(between);
+
+    }
+
+    @Test
+    public void test03() {
+
+        LocalDateTime localTime1 = LocalDateTime.now();
+        LocalDateTime localTime2 = LocalDateTime.of(2020,1,1,10, 20, 30);
+
+        Duration between = Duration.between(localTime2, localTime1);
+        System.out.println(between.getSeconds()/24/3600);
+
+        //相隔多少天
+        long days = between.toDays();
+        System.out.println(days);
+
+    }
+
+    @Test
+    public void test04() {
+
+        LocalDate localTime1 = LocalDate.now();
+        LocalDate localTime2 = LocalDate.of(2020,1,1);
+
+        Duration between = Duration.between(localTime2, localTime1);
+        System.out.println(between.getSeconds()/24/3600);
+
+        //相隔多少天
+        long days = between.toDays();
+        System.out.println(days);
+
+    }
+
+}

day13/src/com/four/day13/demo03/AgeComparator.java

@@ -0,0 +1,14 @@
+package com.four.day13.demo03;
+
+import java.util.Comparator;
+
+//比较器
+public class NameComparator implements Comparator<Person> {
+    @Override
+    public int compare(Person o1, Person o2) {
+
+        int i1 = o1.getName().compareTo(o2.getName());
+
+        return i1;
+    }
+}

day13/src/com/four/day13/demo03/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day13.demo03;public class Demo01 {
+}

day13/src/com/four/day13/demo03/Demo02.java

@@ -0,0 +1,34 @@
+package com.four.day13.demo03;
+
+import java.util.Arrays;
+
+public class Demo01 {
+
+    public static void main(String[] args) {
+
+
+        //Arrays
+
+        int[] arr1 = {1,2,3,4,5};
+        int[] arr2 = {1,2,3,4,5};
+
+        //搜索
+        int i1 = Arrays.binarySearch(arr1, 6);
+        System.out.println(i1);
+
+        //比较
+        int compare = Arrays.compare(arr1, arr2);
+        System.out.println(compare);
+
+        //复制
+        int[] ints = Arrays.copyOf(arr1, 4);
+        System.out.println(Arrays.toString(ints))   ;
+
+        //填充
+        int[] ints2 = new int[4];
+        Arrays.fill(ints2,4);
+
+        System.out.println(Arrays.toString(ints2));
+    }
+
+}

day13/src/com/four/day13/demo03/NameComparator.java

@@ -0,0 +1,2 @@
+package com.four.day13.demo03;public interface NameComparator {
+}

day13/src/com/four/day13/demo03/Person.java

@@ -0,0 +1,2 @@
+package com.four.day13.demo03;public class Person {
+}

day14/day14.iml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

day14/src/com/four/day14/demo01/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo01;public class Demo01 {
+}

day14/src/com/four/day14/demo02/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo02;public class Demo01 {
+}

day14/src/com/four/day14/demo02/Demo02.java

@@ -0,0 +1,62 @@
+package com.four.day14.demo02;
+
+public class Demo01 {
+
+    public static void main(String[] args) {
+        String a = " ";
+        //（1）boolean isEmpty()：字符串是否为空
+        boolean empty = a.isEmpty();
+        //去空格
+        boolean blank = a.isBlank();
+
+        System.out.println(empty);
+        System.out.println(blank);
+
+        String a1 = "abc";
+        //（2）int length()：返回字符串的长度
+        System.out.println(a1.length());
+
+        //（3）String concat(xx)：拼接
+        String def = a1.concat("def");
+        System.out.println(def);
+
+        //（4）boolean equals(Object obj)：比较字符串是否相等，区分大小写
+        boolean equals = a1.equals("abc");
+        // String 比较的是内容 重写。
+        // == 比较地址。
+        // 在Object  ==和 equals 相同的
+
+        // equals 没有重写 使用 ==比较，重写后需要看子类的规则。
+        String s1 = "abc";
+        String s2 = "abc";
+        System.out.println(s1.equals(s2));
+        System.out.println(s1==s2);
+
+        System.out.println(equals);
+
+        //（5）boolean equalsIgnoreCase(Object obj)：比较字符串是否相等，不区分大小写
+        String s3 = "abc";
+        String s4 = "ABC";
+        System.out.println(s3.equalsIgnoreCase(s4));
+
+        //（6）int compareTo(String other)：比较字符串大小，区分大小写，按照Unicode编码值比较大小
+        System.out.println(s3.compareTo(s4));
+
+        //（7）int compareToIgnoreCase(String other)：比较字符串大小，不区分大小写
+        //（8）String toLowerCase()：将字符串中大写字母转为小写
+        //（9）String toUpperCase()：将字符串中小写字母转为大写
+        String upperCase = s3.toUpperCase();
+        System.out.println(upperCase);
+        //（10）String trim()：去掉字符串前后空白符
+        String s5 = " aaaa   ";
+        String trim = s5.trim();
+        System.out.println(trim);
+
+        //（11）public String intern()：结果在常量池中共享
+
+        String s6 = " aaaa   "; //new String("aaaa")
+        String intern = s6.intern();
+        System.out.println(intern);
+
+    }
+}

day14/src/com/four/day14/demo02/Demo03.java

@@ -0,0 +1,27 @@
+package com.four.day14.demo02;
+
+public class Demo03 {
+
+    public static void main(String[] args) {
+        //png gpj
+        String s1 = "pngsad.png";
+        //（11）boolean contains(xx)：是否包含xx
+        boolean png = s1.contains("png");
+        System.out.println(png);
+
+        //（12）int indexOf(xx)：从前往后找当前字符串中xx，即如果有返回第一次出现的下标，要是没有返回-1
+        int i = s1.indexOf("png");
+        System.out.println(i);
+
+        //（13）int indexOf(String str, int fromIndex)：返回指定子字符串在此字符串中第一次出现处的索引，从指定的索引开始
+        int i1 = s1.indexOf("png",2);
+        System.out.println(i1);
+
+        //（14）int lastIndexOf(xx)：从后往前找当前字符串中xx，即如果有返回最后一次出现的下标，要是没有返回-1
+        int i11 = s1.lastIndexOf("png");
+        System.out.println(i11);
+
+        //（15）int lastIndexOf(String str, int fromIndex)：返回指定子字符串在此字符串中最后一次出现处的索引，从指定的索引开始反向搜索。
+
+    }
+}

day14/src/com/four/day14/demo02/Demo04.java

@@ -0,0 +1,28 @@
+package com.four.day14.demo02;
+
+public class Demo03 {
+
+    public static void main(String[] args) {
+        //  16）String substring(int beginIndex) ：
+        //  返回一个新的字符串，它是此字符串的从beginIndex开始截取到最后的一个子字符串。
+        String s1 = "abcdefgh";
+        int length = s1.length();
+        System.out.println(length);
+        String substring = s1.substring( length- 1);
+        System.out.println(substring);
+
+        //（17）String substring(int beginIndex, int endIndex) ：
+        // 返回一个新字符串，它是此字符串从beginIndex开始截取到endIndex(不包含)的一个子字符串。 、
+        String s2 = "abcdefgh";
+        String substring1 = s2.substring(0, 3);
+        System.out.println(substring1);
+
+        String s3 = "abcdefgh.png";
+
+        //截取png
+        int i1 = s3.lastIndexOf("png");
+        String substring2 = s3.substring(i1);
+        System.out.println(substring2);
+
+    }
+}

day14/src/com/four/day14/demo02/Demo05.java

@@ -0,0 +1,40 @@
+package com.four.day14.demo02;
+
+import java.util.Arrays;
+
+public class Demo04 {
+
+    public static void main(String[] args) {
+        String s1 = "fasfasdfasdf";
+        //（18）char charAt(index)：返回[index]位置的字符
+        char c = s1.charAt(0);
+        System.out.println(c);
+
+        //（19）char[] toCharArray()： 将此字符串转换为一个新的字符数组返回
+        char[] charArray = s1.toCharArray();
+        System.out.println(Arrays.toString(charArray));
+
+        //（20）static String valueOf(char[] data)  ：返回指定数组中表示该字符序列的 String
+        char[] chars = {'a', 'b', 'c', 'd', 'e', 'f'};
+        String s = String.valueOf(chars);
+        System.out.println(s);
+
+        //（21）static String valueOf(char[] data, int offset, int count) ：
+        // 返回指定数组中表示该字符序列的 String
+        String s2 = String.valueOf(chars, 1, 3);
+        System.out.println(s2);
+
+
+        byte[] bs = {65,66,67};
+        String s3 = new String(bs);
+        System.out.println(s3);
+
+        //（22）static String copyValueOf(char[] data)：
+        // 返回指定数组中表示该字符序列的 String
+        char[] cs = {'a', 'b', 'c', 'd', 'e', 'f'};
+        String s4 = String.copyValueOf(cs);
+        System.out.println(s4);
+
+        //（23）static String copyValueOf(char[] data, int offset, int count)：返回指定数组中表示该字符序列的
+    }
+}

day14/src/com/four/day14/demo02/Demo06.java

@@ -0,0 +1,21 @@
+package com.four.day14.demo02;
+
+import java.util.Arrays;
+
+public class Demo05 {
+
+    public static void main(String[] args) {
+        String name = "张三";
+        //（24）boolean startsWith(xx)：测试此字符串是否以指定的前缀开始
+        boolean z = name.startsWith("张");
+        System.out.println(z);
+
+        //（25）boolean startsWith(String prefix, int toffset)：
+        // 测试此字符串从指定索引开始查找是否以x开始的
+        String name1 = "a张三fasdfasdfasd";
+        boolean a = name1.startsWith("张", 1);
+        System.out.println(a);
+
+        //（26）boolean endsWith(xx)：测试此字符串是否以指定的后缀结束
+    }
+}

day14/src/com/four/day14/demo02/Demo07.java

@@ -0,0 +1,22 @@
+package com.four.day14.demo02;
+
+public class Demo06 {
+
+    public static void main(String[] args) {
+        //（27）String replace(char oldChar, char newChar)：
+        // 返回一个新的字符串，它是通过用 newChar 替换此字符串中出现的所有 oldChar 得到的。
+        // 不支持正则。
+        String s1 = "C:/Users/secga/Desktop/250714资料/02进阶";
+        String replace1 = s1.replace('U', 'u');
+        System.out.println(replace1);
+
+
+        //（28）String replace(CharSequence target, CharSequence replacement)：
+        // 使用指定的字面值替换序列替换此字符串所有匹配字面值目标序列的子字符串。
+        String s = "返回一个新的字符串，它是通过用 newChar 替换";
+        String replace = s.replace("字符串", "字符序列");
+        System.out.println(replace);
+
+
+    }
+}

day14/src/com/four/day14/demo02/Demo08.java

@@ -0,0 +1,74 @@
+package com.four.day14.demo02;
+
+public class Demo07 {
+
+    public static void main(String[] args) {
+        //- 增
+        //  - append 在尾部添加
+        //  - insert  指定位置添加
+        StringBuilder sb = new StringBuilder();
+        sb.append("java");
+        sb.append("php");
+
+        System.out.println(sb.toString());
+
+        sb.insert(0,"c++");
+
+        System.out.println(sb.toString());
+
+
+        //- 删
+        //  - delete(start, end)
+        //  - deleteCharAt(下标)
+        StringBuilder sb1 = new StringBuilder();
+        sb1.append("java");
+        sb1.append("php");
+
+        StringBuilder delete = sb1.delete(0, 4);
+        System.out.println(delete);
+
+        StringBuilder stringBuilder = delete.deleteCharAt(0).deleteCharAt(0);
+        System.out.println(stringBuilder);
+
+
+        //- 改
+        //  - replace  修改 在执行区间内 修改为 x 字符串
+        //  - setCharAt
+        //  - setLength
+        //  - reverse
+        StringBuilder sb2 = new StringBuilder();
+        sb2.append("java");
+        sb2.append("php");
+
+//        StringBuilder php = sb2.replace(0, 4, "php");
+//        System.out.println(php);
+//        sb2.setCharAt(0,'a');
+
+//        System.out.println(sb2);
+
+        //sb2.setLength(10);
+        System.out.println(sb2.length());
+
+        StringBuilder reverse = sb2.reverse();
+        System.out.println(reverse);
+
+
+        //- 查
+        //  - length
+        //  - indexOf
+        //  - lastIndexOf
+
+        StringBuilder sb3 = new StringBuilder();
+        sb3.append("java");
+        sb3.append("php");
+
+        int i1 = sb3.indexOf("php");
+        System.out.println(i1);
+
+        //转为字符串
+        String string = sb3.toString();
+        //转为StringBuilder
+        StringBuilder sb4 = new StringBuilder(string);
+
+    }
+}

day14/src/com/four/day14/demo02/TestStringConcat.java

@@ -0,0 +1,4 @@
+package com.four.day14.demo02;
+
+public class TestStringConcat {
+}

day14/src/com/four/day14/demo03/MyInteger.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo03;public class MyInteger {
+}

day14/src/com/four/day14/demo03/Person.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo03;public class Person {
+}

day14/src/com/four/day14/demo04/Demo.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo04;public class Demo {
+}

day14/src/com/four/day14/demo04/Demo1.java

@@ -0,0 +1,51 @@
+package com.four.day14.demo04;
+
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.Random;
+
+public class Demo {
+
+    public static void main(String[] args) {
+
+        Random r = new Random();
+        //排序
+        Person[] people = new Person[10];
+        for (int i = 0; i < people.length; i++) {
+            people[i] = new Person();
+            people[i].setAge(r.nextInt(100));
+            Character c = (char)(r.nextInt(26)+65);
+            people[i].setName(c+"");
+        }
+
+        // for ( 类型  变量 ：数组  )
+        for (Person person : people) {
+            System.out.println(person);
+        }
+        System.out.println("====================");
+
+        //定制比较器
+        // 在创建接口和抽象的子类对象的时候 使用。
+
+        Comparator<Person> comparator = new Comparator<>() {
+            //定义比较规则 根据名称排序
+            @Override
+            public int compare(Person o1, Person o2) {
+                return o1.getName().compareTo(o2.getName());
+            }
+        };
+
+        Arrays.sort(people,comparator);
+
+        // for ( 类型  变量 ：数组  )
+        for (Person person : people) {
+            System.out.println(person);
+        }
+
+
+
+
+    }
+
+
+}

day14/src/com/four/day14/demo04/Person.java

@@ -0,0 +1,37 @@
+package com.four.day13.demo03;
+
+
+public class Person  /*implements  Comparable<Person>*/ {
+
+    private String name;
+    private Integer age;
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public Integer getAge() {
+        return age;
+    }
+
+    public void setAge(Integer age) {
+        this.age = age;
+    }
+    //    @Override
+//    public int compareTo(Person o) {
+//        return 0;
+//    }
+
+
+    @Override
+    public String toString() {
+        return "Person{" +
+                "name='" + name + '\'' +
+                ", age=" + age +
+                '}';
+    }
+}

day14/src/com/four/day14/demo05/Demo.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo05;public class Demo {
+}

day14/src/com/four/day14/demo05/Person.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo05;public class Person {
+}

day14/src/com/four/day14/demo06/Demo01.java

@@ -0,0 +1,24 @@
+package com.four.day14.demo05.demo06;
+
+public class Demo01 {
+    public static void main(String[] args) {
+        int[] a = new int[10];
+
+
+        for (int i = 0; i < a.length; i++) {
+            System.out.println(a[i]);
+        }
+
+        //增强for
+        // for ( 类型  元素变量 : 数组  )
+        // 数组.for
+        System.out.println("------------");
+        for (int i : a) {
+            System.out.println(i);
+        }
+
+
+    }
+
+
+}

day14/src/com/four/day14/demo06/Demo02.java

@@ -0,0 +1,24 @@
+package com.four.day14.demo06;
+
+public class Demo02 {
+    public static void main(String[] args) {
+        int[] a = new int[10];
+
+
+        for (int i = 0; i < a.length; i++) {
+            System.out.println(a[i]);
+        }
+
+        //增强for
+        // for ( 类型  元素变量 : 数组  )
+        // 数组.for
+        System.out.println("------------");
+        for (int i : a) {
+            System.out.println(i);
+        }
+
+
+    }
+
+
+}

day14/src/com/four/day14/demo06/Tagg.java

@@ -0,0 +1,2 @@
+package com.four.day14.demo06;public @interface Tagg {
+}

day15/day15.iml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

day15/src/com/four/day15/Demo01.java

@@ -0,0 +1,2 @@
+package com.four.day15;public class Demo01 {
+}