From 722ec41fd2fb112d03ac1356c26c9e3cd8fd28ea Mon Sep 17 00:00:00 2001
From: CZHXX <14938243+czhxx@user.noreply.gitee.com>
Date: Mon, 14 Oct 2024 03:35:00 +0000
Subject: [PATCH] w w

Signed-off-by: CZHXX <14938243+czhxx@user.noreply.gitee.com>
---
 ForDemo1.java | 35 +++++++++++++++++++++++++++++++++++
 ForDemo2.java | 21 +++++++++++++++++++++
 ForDemo3.java | 21 +++++++++++++++++++++
 IfDemo1.java  | 18 ++++++++++++++++++
 IfDemo2.java  | 16 ++++++++++++++++
 Student.java  | 38 ++++++++++++++++++++++++++++++++++++++
 da.java       | 12 ++++++++++++
 7 files changed, 161 insertions(+)
 create mode 100644 ForDemo1.java
 create mode 100644 ForDemo2.java
 create mode 100644 ForDemo3.java
 create mode 100644 IfDemo1.java
 create mode 100644 IfDemo2.java
 create mode 100644 Student.java
 create mode 100644 da.java

diff --git a/ForDemo1.java b/ForDemo1.java
new file mode 100644
index 000000000..da881ebb3
--- /dev/null
+++ b/ForDemo1.java
@@ -0,0 +1,35 @@
+public class ForDemo1 {
+    public static void main(String[] args) {
+        System.out.println("----3次Hello World----");
+        for (int i = 0; i < 3; i++) {
+            if (i == 1) {
+                break; // 当i等于1时，跳出循环
+            }
+            System.out.println("Hello World");
+        }
+
+        System.out.println("----4次Hello MySQL----");
+        for (int i = 1; i < 5; i++) {
+            if (i == 3) {
+                continue; // 当i等于3时，跳过当前迭代
+            }
+            System.out.println("Hello MySQL");
+        }
+
+        System.out.println("----5次Hello Spring----");
+        for (int i = 1; i <= 5; i++) {
+            if (i == 3) {
+                continue; // 当i等于3时，跳过当前迭代
+            }
+            System.out.println("Hello Spring");
+        }
+
+        System.out.println("----3次Hello Redis----");
+        for (int i = 1; i <= 5; i += 2) {
+            if (i == 3) {
+                break; // 当i等于3时，跳出循环
+            }
+            System.out.println("Hello Redis");
+        }
+    }
+}
diff --git a/ForDemo2.java b/ForDemo2.java
new file mode 100644
index 000000000..254408732
--- /dev/null
+++ b/ForDemo2.java
@@ -0,0 +1,21 @@
+public class ForDemo2 {
+    public static void main(String[] args){
+        int [] numbers = {10, 20, 30, 40, 50};
+        for(int x : numbers ){
+            if (x == 30) {
+                break; // 当x等于30时，跳出循环
+            }
+            System.out.print( x );
+            System.out.print(",");
+        }
+        System.out.println();
+        String [] names ={"James", "Larry", "Tom", "Lacy"};
+        for( String name : names ) {
+            if (name.equals("Tom")) {
+                continue; // 当name等于"Tom"时，跳过当前循环，继续下一个循环
+            }
+            System.out.print( name );
+            System.out.print(",");
+        }
+    }
+}
diff --git a/ForDemo3.java b/ForDemo3.java
new file mode 100644
index 000000000..bf452b6aa
--- /dev/null
+++ b/ForDemo3.java
@@ -0,0 +1,21 @@
+public class ForDemo3 {
+    public static void main(String[] args) {
+        // 使用break
+        System.out.println("----使用break----");
+        for (int i = 1; i <= 5; i++) {
+            if (i == 3) {
+                break;
+            }
+            System.out.println("Hello Break");
+        }
+
+        // 使用continue
+        System.out.println("----使用continue----");
+        for (int i = 1; i <= 5; i++) {
+            if (i == 3) {
+                continue;
+            }
+            System.out.println("Hello Continue");
+        }
+    }
+}
diff --git a/IfDemo1.java b/IfDemo1.java
new file mode 100644
index 000000000..b9776de43
--- /dev/null
+++ b/IfDemo1.java
@@ -0,0 +1,18 @@
+public class IfDemo1 {
+    public static void main(String[] args) {
+        // 格式3： if(条件表达式){ 代码... } else if(条件表达式){ 代码... } ... else{ 代码... }
+        int score = 95;
+        // 绩效：0-60 C，60-80 B，80-90 A，90-100 A+
+        if (score >= 0 && score < 60) {
+            System.out.println("分数是：" + score + "，绩效是：C");
+        } else if (score >= 60 && score < 80) {
+            System.out.println("分数是：" + score + "，绩效是：B");
+        } else if (score >= 80 && score < 90) {
+            System.out.println("分数是：" + score + "，绩效是：A");
+        } else if (score >= 90 && score <= 100) {
+            System.out.println("分数是：" + score + "，绩效是：A+");
+        } else {
+            System.out.println("录入的分数有毛病！");
+        }
+    }
+}
\ No newline at end of file
diff --git a/IfDemo2.java b/IfDemo2.java
new file mode 100644
index 000000000..0080f8f70
--- /dev/null
+++ b/IfDemo2.java
@@ -0,0 +1,16 @@
+public class IfDemo2 {
+    public static void main(String[] args) {
+        // 嵌套的 if…else 语句
+        int x = 30;
+        int y = 10;
+        if (x == 30) {
+            if (y == 20) {
+                System.out.print("X = 30 and Y = 20");
+            } else {
+                System.out.println("X = 30 and Y != 20");
+            }
+        } else {
+            System.out.println("X != 30");
+        }
+    }
+}
diff --git a/Student.java b/Student.java
new file mode 100644
index 000000000..5c1a9fc18
--- /dev/null
+++ b/Student.java
@@ -0,0 +1,38 @@
+public class Student {
+    // 1.局部变量：在方法、构造函数或块内部声明的变量。
+    public void run() {
+        String weight = "100斤"; // 局部变量weight，必须有初始值。
+        // 因为实例变量age没赋值，所以默认是0
+        System.out.println(name + "现在" + age + "岁"); // 小明现在0岁
+        System.out.println(name + weight + "，跑得很快"); // 小明100斤，跑得很快
+    }
+
+    // 2.实例变量：在类中声明，但在方法、构造函数或块之外。
+    public String name = "小明"; // 公有实例变量name对子类可见
+    private int age; // 私有实例变量age，仅在该类可见，不赋值，默认是0
+
+    // main方法，程序入口
+    public static void main(String[] args) {
+        Student.onLineNumber++; // 22
+        System.out.println(onLineNumber);
+        Student student = new Student();
+        student.run();
+        student.eat("方便面");
+        student.study();
+    }
+
+    // 3.类变量：在类中用 static 关键字声明的变量，它们属于类而不是实例。
+    public static int onLineNumber = 21;
+    private String major = "计算机科学";
+
+    // 4.参数变量：是方法或构造函数声明中的变量
+    public void eat(String food) { // 参数变量food
+        System.out.println(name + "喜欢吃" + food); // 小明喜欢吃方便面
+    }
+
+    // 自定义方法
+    public void study() {
+        System.out.println(name + "正在学习" + major);
+    }
+}
+
diff --git a/da.java b/da.java
new file mode 100644
index 000000000..dec1539b3
--- /dev/null
+++ b/da.java
@@ -0,0 +1,12 @@
+public class da {
+    public static void main(String[] args) {
+        int n = 7;
+        if (n >= 0 && n < 10) {
+            for (int i = 0; i < n; i++) {
+                System.out.println("He" + n + n +"o" + " Wor" + n + "d");
+            }
+        } else {
+            System.out.println("n>10");
+        }
+    }
+}