style:fmt

.gitignore

@@ -1,95 +0,0 @@
-### Compiled class files
-*.class
-
-### Log files
-*.log
-
-### BlueJ files
-*.ctxt
-
-### Mobile Tools for Java (J2ME)
-.mtj.tmp/
-
-### Package Files
-*.jar
-*.war
-*.nar
-*.ear
-*.zip
-*.tar.gz
-*.rar
-
-### VM crash logs
-hs_err_pid*
-replay_pid*
-
-# ========================
-# Maven
-# ========================
-target/
-pom.xml.tag
-pom.xml.releaseBackup
-pom.xml.versionsBackup
-pom.xml.next
-release.properties
-dependency-reduced-pom.xml
-buildNumber.properties
-.mvn/timing.properties
-.mvn/wrapper/maven-wrapper.jar
-
-# ========================
-# Gradle
-# ========================
-.gradle/
-build/
-!gradle-wrapper.jar
-!*/src/main/**/build/
-!*/src/test/**/build/
-
-### Avoid ignoring Gradle wrapper
-gradle-app.setting
-
-# ========================
-# IntelliJ IDEA
-# ========================
-.idea/
-*.iml
-*.ipr
-*.iws
-out/
-
-# ========================
-# Eclipse
-# ========================
-.project
-.classpath
-.cproject
-.settings/
-bin/
-tmp/
-
-# ========================
-# NetBeans
-# ========================
-nbproject/private/
-nbbuild/
-dist/
-nbdist/
-.nb-gradle/
-
-# ========================
-# VS Code
-# ========================
-.vscode/
-
-# ========================
-# OS files
-# ========================
-# macOS
-.DS_Store
-
-# Windows
-Thumbs.db
-
-#local
-com/study/test/

com/study/demo/Demo.java

@@ -1,7 +1,7 @@
 package com.study.demo;
 
 public class Demo {
-  public static void main(String[] args) {
+	public static void main(String [] args) {
-    System.out.println("HelloWorld!");
+		System.out.println("HelloWorld!");
-  }
+		}
 }

com/study/demo/test1_1.java

@@ -1,15 +1,13 @@
 package com.study.demo;
-
 import java.util.Scanner;
-
 // I am 212306206
 public class test1_type {
-  public static void main(String[] args) {
+	public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+		Scanner scanner = new Scanner (System.in);
-    int a = scanner.nextInt();
+		int a = scanner.nextInt();
-    int b = scanner.nextInt();
+		int b = scanner.nextInt();
-    int sum = a + b;
+		int sum = a + b;
-    System.out.println(a + " + " + b + " = " + sum);
+		System.out.println(a + " + " + b + " = " + sum);
-    scanner.close();
+		scanner.close();
-  }
+	}
 }

com/study/demo/test1_2.java

@@ -1,15 +1,16 @@
 package com.study.demo;
 
 public class test2_for {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    int[] numbers = new int[5];
+        int[] numbers = new int[5];
-    for (int i = 0; i < numbers.length; i++) {
+        for (int i = 0; i < numbers.length; i++) {
-      numbers[i] = i * 10;
+            numbers[i] = i * 10;
-    }
+        }
 
-    System.out.print("数组内容: ");
+        System.out.print("数组内容: ");
-    for (int i = 0; i < numbers.length; i++) {
+        for (int i = 0; i < numbers.length; i++) {
-      System.out.print(numbers[i] + " ");
+            System.out.print(numbers[i] + " ");
+        }
     }
-  }
 }
+

com/study/demo/test1_3.java

@@ -1,18 +1,19 @@
 package com.study.demo;
 
 public class test3_1_99 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    int[] numbers = new int[99];
+        int[] numbers = new int[99];
 
-    for (int i = 0; i < numbers.length; i++) {
+        for (int i = 0; i < numbers.length; i++) {
-      numbers[i] = i + 1;
+            numbers[i] = i + 1;
+        }
+
+        int sum = 0;
+        for (int i = 0; i < numbers.length; i++) {
+            sum += numbers[i];
+        }
+
+        System.out.println("1+2+...+99 的和 = " + sum);
     }
-
-    int sum = 0;
-    for (int i = 0; i < numbers.length; i++) {
-      sum += numbers[i];
-    }
-
-    System.out.println("1+2+...+99 的和 = " + sum);
-  }
 }
+

com/study/demo/test2_2.java

@@ -1,15 +1,14 @@
 package com.study.demo;
-
 import java.util.Scanner;
 
 public class test5 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int a = scanner.nextInt();
+        int a = scanner.nextInt();
-    int b = scanner.nextInt();
+        int b = scanner.nextInt();
-    int c = scanner.nextInt();
+        int c = scanner.nextInt();
-    double pi = 3.1415926535;
+        double pi = 3.1415926535;
-    double area = a * b * c + a * c + (pi * c * c) / 4;
+        double area = a * b * c + a * c + (pi * c * c) / 4;
-    System.out.printf("%.3f\n", area / 10000);
+        System.out.printf("%.3f\n", area / 10000);
-  }
+    }
-}
+}

com/study/demo/test2_3.java

@@ -3,10 +3,10 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test6 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int n = scanner.nextInt();
+        int n = scanner.nextInt();
-    int result = 1 << n;
+        int result = 1 << n;
-    System.out.println(result);
+        System.out.println(result);
-  }
+    }
-}
+}

com/study/demo/test2_4.java

@@ -3,12 +3,12 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test7 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int x = scanner.nextInt();
+        int x = scanner.nextInt();
-    int y = scanner.nextInt();
+        int y = scanner.nextInt();
-    int startYear = 2016, startMonth = 8;
+        int startYear = 2016, startMonth = 8;
-    int totalMonths = (x - startYear) * 12 + y - startMonth + 1;
+        int totalMonths = (x - startYear) * 12 + y - startMonth + 1;
-    System.out.println(totalMonths);
+        System.out.println(totalMonths);
-  }
+    }
-}
+}

com/study/demo/test2_5.java

@@ -3,17 +3,17 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test8 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int x = scanner.nextInt();
+        int x = scanner.nextInt();
-    int k = scanner.nextInt();
+        int k = scanner.nextInt();
-    int a = x / 1000 % k;
+        int a = x / 1000 % k;
-    int b = x / 100 % 10 % k;
+        int b = x / 100 % 10 % k;
-    int c = x / 10 % 10 % k;
+        int c = x / 10 % 10 % k;
-    int d = x % 10 % k;
+        int d = x % 10 % k;
-    System.out.print(a);
+        System.out.print(a);
-    System.out.print(b);
+        System.out.print(b);
-    System.out.print(c);
+        System.out.print(c);
-    System.out.println(d);
+        System.out.println(d);
-  }
+    }
 }

com/study/demo/test3_1.java

@@ -3,20 +3,20 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_1 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int n = scanner.nextInt();
+        int n = scanner.nextInt();
-    int[] arr = new int[n];
+        int[] arr = new int[n];
-    for (int i = 0; i < n; i++) {
+        for (int i = 0; i < n; i++) {
-      arr[i] = scanner.nextInt();
+            arr[i] = scanner.nextInt();
+        }
+        for (int i = 0; i < n / 2; i++) {
+            int temp = arr[i];
+            arr[i] = arr[n - 1 - i];
+            arr[n - 1 - i] = temp;
+        }
+        for (int i = 0; i < n; i++) {
+            System.out.print(arr[i] + (i == n - 1 ? "" : " "));
+        }
     }
-    for (int i = 0; i < n / 2; i++) {
-      int temp = arr[i];
-      arr[i] = arr[n - 1 - i];
-      arr[n - 1 - i] = temp;
-    }
-    for (int i = 0; i < n; i++) {
-      System.out.print(arr[i] + (i == n - 1 ? "" : " "));
-    }
-  }
 }

com/study/demo/test3_2.java

@@ -3,21 +3,21 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_2 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int n = scanner.nextInt();
+        int n = scanner.nextInt();
-    int[] a = new int[n];
+        int[] a = new int[n];
-    int[] b = new int[n];
+        int[] b = new int[n];
-    for (int i = 0; i < n; i++) {
+        for (int i = 0; i < n; i++) {
-      a[i] = scanner.nextInt();
+            a[i] = scanner.nextInt();
+        }
+        for (int i = 0; i < n; i++) {
+            b[i] = scanner.nextInt();
+        }
+        int sum = 0;
+        for (int i = 0; i < n; i++) {
+            sum += a[i] * b[i];
+        }
+        System.out.println(sum);
     }
-    for (int i = 0; i < n; i++) {
-      b[i] = scanner.nextInt();
-    }
-    int sum = 0;
-    for (int i = 0; i < n; i++) {
-      sum += a[i] * b[i];
-    }
-    System.out.println(sum);
-  }
 }

com/study/demo/test3_3.java

@@ -3,23 +3,23 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_3 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int n = scanner.nextInt();
+        int n = scanner.nextInt();
-    int[] arr = new int[n];
+        int[] arr = new int[n];
-    for (int i = 0; i < n; i++) {
+        for (int i = 0; i < n; i++) {
-      arr[i] = scanner.nextInt();
+            arr[i] = scanner.nextInt();
-    }
+        }
-    int maxLen = 1, currentLen = 1;
+        int maxLen = 1, currentLen = 1;
-    for (int i = 1; i < n; i++) {
+        for (int i = 1; i < n; i++) {
-      if (arr[i] == arr[i - 1]) {
+            if (arr[i] == arr[i - 1]) {
-        currentLen++;
+                currentLen++;
-      } else {
+            } else {
+                maxLen = Math.max(maxLen, currentLen);
+                currentLen = 1;
+            }
+        }
         maxLen = Math.max(maxLen, currentLen);
-        currentLen = 1;
+        System.out.println(maxLen);
-      }
     }
-    maxLen = Math.max(maxLen, currentLen);
-    System.out.println(maxLen);
-  }
 }

com/study/demo/test3_4.java

@@ -3,21 +3,21 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_4 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int n = scanner.nextInt();
+        int n = scanner.nextInt();
-    int m = scanner.nextInt();
+        int m = scanner.nextInt();
-    int[][] image = new int[n][m];
+        int[][] image = new int[n][m];
-    for (int i = 0; i < n; i++) {
+        for (int i = 0; i < n; i++) {
-      for (int j = 0; j < m; j++) {
+            for (int j = 0; j < m; j++) {
-        image[i][j] = scanner.nextInt();
+                image[i][j] = scanner.nextInt();
-      }
+            }
+        }
+        for (int j = 0; j < m; j++) {
+            for (int i = n - 1; i >= 0; i--) {
+                System.out.print(image[i][j] + (i == 0 ? "" : " "));
+            }
+            System.out.println();
+        }
     }
-    for (int j = 0; j < m; j++) {
-      for (int i = n - 1; i >= 0; i--) {
-        System.out.print(image[i][j] + (i == 0 ? "" : " "));
-      }
-      System.out.println();
-    }
-  }
 }

com/study/demo/test3_5.java

@@ -3,32 +3,32 @@ package com.study.demo;
 import java.util.Scanner;
 
 public class test3_5 {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Scanner scanner = new Scanner(System.in);
+        Scanner scanner = new Scanner(System.in);
-    int n = scanner.nextInt();
+        int n = scanner.nextInt();
-    int[] t = new int[n - 1];
+        int[] t = new int[n - 1];
-    int[] s = new int[n];
+        int[] s = new int[n];
-    for (int i = 0; i < n - 1; i++) {
+        for (int i = 0; i < n - 1; i++) {
-      t[i] = scanner.nextInt();
+            t[i] = scanner.nextInt();
-    }
+        }
-    for (int i = 0; i < n; i++) {
+        for (int i = 0; i < n; i++) {
-      s[i] = scanner.nextInt();
+            s[i] = scanner.nextInt();
-    }
+        }
-    int x = scanner.nextInt();
+        int x = scanner.nextInt();
-    int y = scanner.nextInt();
+        int y = scanner.nextInt();
 
-    int total = 0;
+        int total = 0;
-    if (x < y) {
+        if (x < y) {
-      for (int i = x - 1; i < y - 1; i++) {
+            for (int i = x - 1; i < y - 1; i++) {
-        total += s[i] + t[i];
+                total += s[i] + t[i];
-      }
+            }
-      total += s[y - 1];
+            total += s[y - 1];
-    } else {
+        } else {
-      for (int i = x - 1; i >= y; i--) {
+            for (int i = x - 1; i >= y; i--) {
-        total += s[i] + (i > 0 ? t[i - 1] : 0);
+                total += s[i] + (i > 0 ? t[i - 1] : 0);
-      }
+            }
-      total += s[y - 1];
+            total += s[y - 1];
+        }
+        System.out.println(total);
     }
-    System.out.println(total);
-  }
 }

com/study/demo2/Account.java

@@ -1,36 +1,36 @@
 package com.study.demo2;
 
 public class Account {
-  private String accountId;
+    private String accountId;
-  private String owner;
+    private String owner;
-  private double balance;
+    private double balance;
 
-  public Account(String accountId, String owner, double balance) {
+    public Account(String accountId, String owner, double balance) {
-    this.accountId = accountId;
+        this.accountId = accountId;
-    this.owner = owner;
+        this.owner = owner;
-    this.balance = balance;
+        this.balance = balance;
-  }
-
-  public void deposit(double amount) {
-    if (amount > 0) {
-      balance += amount;
     }
-  }
 
-  public void withdraw(double amount) {
+    public void deposit(double amount) {
-    if (amount > 0 && amount <= balance) {
+        if (amount > 0) {
-      balance -= amount;
+            balance += amount;
+        }
     }
-  }
 
-  public void transfer(Account target, double amount) {
+    public void withdraw(double amount) {
-    if (amount > 0 && amount <= balance) {
+        if (amount > 0 && amount <= balance) {
-      this.balance -= amount;
+            balance -= amount;
-      target.balance += amount;
+        }
     }
-  }
 
-  public double getBalance() {
+    public void transfer(Account target, double amount) {
-    return balance;
+        if (amount > 0 && amount <= balance) {
-  }
+            this.balance -= amount;
-}
+            target.balance += amount;
+        }
+    }
+
+    public double getBalance() {
+        return balance;
+    }
+}

com/study/demo2/Account_Main.java

@@ -1,15 +1,15 @@
 package com.study.demo2;
 
 public class Main {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Account acc1 = new Account("A001", "张三", 1000);
+        Account acc1 = new Account("A001", "张三", 1000);
-    Account acc2 = new Account("A002", "李四", 500);
+        Account acc2 = new Account("A002", "李四", 500);
-
+        
-    acc1.deposit(200);
+        acc1.deposit(200);
-    acc1.withdraw(100);
+        acc1.withdraw(100);
-    acc1.transfer(acc2, 300);
+        acc1.transfer(acc2, 300);
-
+        
-    System.out.println("账户1余额:" + acc1.getBalance());
+        System.out.println("账户1余额:" + acc1.getBalance());
-    System.out.println("账户2余额:" + acc2.getBalance());
+        System.out.println("账户2余额:" + acc2.getBalance());
-  }
+    }
-}
+}

com/study/demo2/Animal.java

@@ -1,45 +1,44 @@
 package com.study.demo2;
 
 public abstract class Animal {
-  protected String name;
+    protected String name;
 
-  public Animal(String name) {
+    public Animal(String name) {
-    this.name = name;
+        this.name = name;
-  }
+    }
 
-  public abstract void makeSound();
+    public abstract void makeSound();
-
+    public abstract void move();
-  public abstract void move();
 }
 
 class Dog extends Animal {
-  public Dog(String name) {
+    public Dog(String name) {
-    super(name);
+        super(name);
-  }
+    }
 
-  @Override
+    @Override
-  public void makeSound() {
+    public void makeSound() {
-    System.out.println(name + " 汪汪叫");
+        System.out.println(name + " 汪汪叫");
-  }
+    }
 
-  @Override
+    @Override
-  public void move() {
+    public void move() {
-    System.out.println(name + " 跑动");
+        System.out.println(name + " 跑动");
-  }
+    }
 }
 
 class Bird extends Animal {
-  public Bird(String name) {
+    public Bird(String name) {
-    super(name);
+        super(name);
-  }
+    }
 
-  @Override
+    @Override
-  public void makeSound() {
+    public void makeSound() {
-    System.out.println(name + " 叽叽喳喳");
+        System.out.println(name + " 叽叽喳喳");
-  }
+    }
 
-  @Override
+    @Override
-  public void move() {
+    public void move() {
-    System.out.println(name + " 飞翔");
+        System.out.println(name + " 飞翔");
-  }
+    }
-}
+}

com/study/demo2/Animal_Main.java

@@ -1,12 +1,12 @@
 package com.study.demo2;
 
 public class Main {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Animal dog = new Dog("Buddy");
+        Animal dog = new Dog("Buddy");
-    Animal bird = new Bird("Tweety");
+        Animal bird = new Bird("Tweety");
-    dog.makeSound();
+        dog.makeSound();
-    dog.move();
+        dog.move();
-    bird.makeSound();
+        bird.makeSound();
-    bird.move();
+        bird.move();
-  }
+    }
-}
+}

com/study/demo2/Rectangle.java

@@ -1,38 +1,37 @@
 package com.study.demo2;
 
 public class Rectangle {
-  private double width = 1.0;
+    private double width = 1.0;
-  private double height = 1.0;
+    private double height = 1.0;
 
-  public Rectangle() {
+    public Rectangle() {}
-  }
 
-  public Rectangle(double width, double height) {
+    public Rectangle(double width, double height) {
-    this.width = width;
+        this.width = width;
-    this.height = height;
+        this.height = height;
-  }
+    }
 
-  public double getArea() {
+    public double getArea() {
-    return width * height;
+        return width * height;
-  }
+    }
 
-  public double getPerimeter() {
+    public double getPerimeter() {
-    return 2 * (width + height);
+        return 2 * (width + height);
-  }
+    }
 
-  public double getWidth() {
+    public double getWidth() {
-    return width;
+        return width;
-  }
+    }
 
-  public void setWidth(double width) {
+    public void setWidth(double width) {
-    this.width = width;
+        this.width = width;
-  }
+    }
 
-  public double getHeight() {
+    public double getHeight() {
-    return height;
+        return height;
-  }
+    }
 
-  public void setHeight(double height) {
+    public void setHeight(double height) {
-    this.height = height;
+        this.height = height;
-  }
+    }
 }

com/study/demo2/Rectangle_Main.java

@@ -1,18 +1,18 @@
 package com.study.demo2;
 
 public class Main {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    Rectangle rect1 = new Rectangle(5.0, 3.0);
+        Rectangle rect1 = new Rectangle(5.0, 3.0);
-    System.out.println("面积:" + rect1.getArea());
+        System.out.println("面积:" + rect1.getArea());
-    System.out.println("周长:" + rect1.getPerimeter());
+        System.out.println("周长:" + rect1.getPerimeter());
-
+        
-    Rectangle rect2 = new Rectangle();
+        Rectangle rect2 = new Rectangle();
-    System.out.println("默认面积:" + rect2.getArea());
+        System.out.println("默认面积:" + rect2.getArea());
-    System.out.println("默认周长:" + rect2.getPerimeter());
+        System.out.println("默认周长:" + rect2.getPerimeter());
-
+        
-    rect2.setWidth(2.5);
+        rect2.setWidth(2.5);
-    rect2.setHeight(4.0);
+        rect2.setHeight(4.0);
-    System.out.println("修改后面积:" + rect2.getArea());
+        System.out.println("修改后面积:" + rect2.getArea());
-    System.out.println("修改后周长:" + rect2.getPerimeter());
+        System.out.println("修改后周长:" + rect2.getPerimeter());
-  }
+    }
-}
+}

com/study/demo2/Student.java

@@ -1,46 +1,40 @@
 package com.study.demo2;
 
 public class Student {
-  private String id;
+    private String id;
-  private String name;
+    private String name;
-  private int[] score = new int[10];
+    private int[] score = new int[10];
 
-  public Student(String id, String name, int[] scores) {
+    public Student(String id, String name, int[] scores) {
-    this.id = id;
+        this.id = id;
-    this.name = name;
+        this.name = name;
-    if (scores.length == 10) {
+        if (scores.length == 10) {
-      this.score = scores;
+            this.score = scores;
+        }
     }
-  }
 
-  public double getAverage() {
+    public double getAverage() {
-    int sum = 0;
+        int sum = 0;
-    for (int s : score) {
+        for (int s : score) {
-      sum += s;
+            sum += s;
+        }
+        return (double) Math.round((sum / 10.0) * 100) / 100;
     }
-    return (double) Math.round((sum / 10.0) * 100) / 100;
-  }
 
-  public int getMaxScore() {
+    public int getMaxScore() {
-    int max = score[0];
+        int max = score[0];
-    for (int s : score) {
+        for (int s : score) {
-      if (s > max)
+            if (s > max) max = s;
-        max = s;
+        }
+        return max;
     }
-    return max;
-  }
 
-  public char getGrade() {
+    public char getGrade() {
-    double avg = getAverage();
+        double avg = getAverage();
-    if (avg >= 90)
+        if (avg >= 90) return 'A';
-      return 'A';
+        else if (avg >= 80) return 'B';
-    else if (avg >= 80)
+        else if (avg >= 70) return 'C';
-      return 'B';
+        else if (avg >= 60) return 'D';
-    else if (avg >= 70)
+        else return 'E';
-      return 'C';
+    }
-    else if (avg >= 60)
+}
-      return 'D';
-    else
-      return 'E';
-  }
-}

com/study/demo2/Student_Main.java

@@ -1,11 +1,12 @@
 package com.study.demo2;
 
 public class Main {
-  public static void main(String[] args) {
+    public static void main(String[] args) {
-    int[] scores = { 85, 90, 78, 92, 88, 76, 95, 89, 79, 94 };
+        int[] scores = {85, 90, 78, 92, 88, 76, 95, 89, 79, 94};
-    Student student = new Student("5001", "张三", scores);
+        Student student = new Student("5001", "张三", scores);
-    System.out.println("平均分: " + student.getAverage());
+        
-    System.out.println("最高分: " + student.getMaxScore());
+        System.out.println("平均分: " + student.getAverage());
-    System.out.println("等级: " + student.getGrade());
+        System.out.println("最高分: " + student.getMaxScore());
-  }
+        System.out.println("等级: " + student.getGrade());
-}
+    }
+}

com/study/demo4/AlipayPayment.java

@@ -1,9 +0,0 @@
-package com.study.demo4;
-
-class AlipayPayment implements PaymentProcessor {
-  @Override
-  public boolean pay(double amount) {
-    System.out.println("支付宝支付: " + amount);
-    return true;
-  }
-}

com/study/demo4/BikeDeliveryCalculator.java

@@ -1,11 +0,0 @@
-package com.study.demo4;
-
-class BikeDeliveryCalculator implements DeliveryFeeCalculator {
-  @Override
-  public double calculateFee(double distance) {
-    if (distance <= 5) {
-      return 5.0; // 起步价
-    }
-    return 5.0 + (distance - 5) * 1.5;
-  }
-}

com/study/demo4/Cardeliverycalculator.java

@@ -1,12 +0,0 @@
-package com.study.demo4;
-
-class CarDeliveryCalculator implements DeliveryFeeCalculator {
-  @Override
-  public double calculateFee(double distance) {
-    if (distance <= 5) {
-      return 10.0; // 起步价
-    }
-    return 10.0 + (distance - 5) * 2.0;
-  }
-}
-

com/study/demo4/CreditCardPayment.java

@@ -1,9 +0,0 @@
-package com.study.demo4;
-
-class CreditCardPayment implements PaymentProcessor {
-  @Override
-  public boolean pay(double amount) {
-    System.out.println("银行卡支付: " + amount);
-    return true;
-  }
-}

com/study/demo4/DeliveryFeeCalculator.java

@@ -1,5 +0,0 @@
-package com.study.demo4;
-
-interface DeliveryFeeCalculator {
-  double calculateFee(double distance);
-}

com/study/demo4/HomeAppliance.java

@@ -1,26 +0,0 @@
-package com.study.demo4;
-
-abstract class HomeAppliance implements SmartDevice {
-  protected String name;
-  protected boolean isOn;
-
-  public HomeAppliance(String name) {
-    this.name = name;
-    this.isOn = false;
-  }
-
-  @Override
-  public void turnOn() {
-    isOn = true;
-  }
-
-  @Override
-  public void turnOff() {
-    isOn = false;
-  }
-
-  @Override
-  public String getStatus() {
-    return name + " is " + (isOn ? "ON" : "OFF");
-  }
-}

com/study/demo4/HomeController.java

@@ -1,21 +0,0 @@
-package com.study.demo4;
-
-import java.util.ArrayList;
-import java.util.List;
-
-class HomeController {
-  private List<SmartDevice> devices = new ArrayList<>();
-
-  public void addDevice(SmartDevice device) {
-    devices.add(device);
-  }
-
-  public String getDeviceStatus(String name) {
-    for (SmartDevice device : devices) {
-      if (device.getStatus().contains(name)) {
-        return device.getStatus();
-      }
-    }
-    return "Device not found";
-  }
-}

com/study/demo4/PaymentFactory.java

@@ -1,16 +0,0 @@
-package com.study.demo4;
-
-class PaymentFactory {
-  public static PaymentProcessor getProcessor(String type) {
-    switch (type.toLowerCase()) {
-      case "wechat":
-        return new WechatPayment();
-      case "alipay":
-        return new AlipayPayment();
-      case "card":
-        return new CreditCardPayment();
-      default:
-        throw new IllegalArgumentException("不支持的支付方式");
-    }
-  }
-}

com/study/demo4/PaymentProcessor.java

@@ -1,6 +0,0 @@
-package com.study.demo4;
-
-interface PaymentProcessor {
-  boolean pay(double amount);
-}
-

com/study/demo4/SmartAirConditioner.java

@@ -1,7 +0,0 @@
-package com.study.demo4;
-
-class SmartAirConditioner extends HomeAppliance {
-  public SmartAirConditioner(String name) {
-    super(name);
-  }
-}

com/study/demo4/SmartDevice.java

@@ -1,7 +0,0 @@
-package com.study.demo4;
-
-interface SmartDevice {
-  void turnOn();
-  void turnOff();
-  String getStatus();
-}

com/study/demo4/SmartLight.java

@@ -1,7 +0,0 @@
-package com.study.demo4;
-
-class SmartLight extends HomeAppliance {
-  public SmartLight(String name) {
-    super(name);
-  }
-}

com/study/demo4/SmartMasher.java

@@ -1,7 +0,0 @@
-package com.study.demo4;
-
-class SmartMasher extends HomeAppliance {
-  public SmartMasher(String name) {
-    super(name);
-  }
-}

com/study/demo4/TestControl.java

@@ -1,31 +0,0 @@
-package com.study.demo4;
-
-import java.util.ArrayList;
-import java.util.List;
-
-public class TestControl {
-  public static void main(String[] args) {
-    HomeController controller = new HomeController();
-
-    // 创建设备
-    SmartLight light = new SmartLight("Living Room Light");
-    SmartAirConditioner ac = new SmartAirConditioner("Bedroom AC");
-    SmartMasher masher = new SmartMasher("Kitchen Masher");
-
-    // 添加到控制器
-    controller.addDevice(light);
-    controller.addDevice(ac);
-    controller.addDevice(masher);
-
-    // 测试设备状态
-    light.turnOff();
-    ac.turnOff();
-    masher.turnOn();
-
-    // 查询状态
-    System.out.println(controller.getDeviceStatus("Living Room Light"));
-    System.out.println(controller.getDeviceStatus("Bedroom AC"));
-    System.out.println(controller.getDeviceStatus("Kitchen Masher"));
-    System.out.println(controller.getDeviceStatus("Non-existent Device"));
-  }
-}

com/study/demo4/TestPay.java

@@ -1,8 +0,0 @@
-package com.study.demo4;
-
-public class TestPay {
-  public static void main(String[] args) {
-    PaymentProcessor processor = PaymentFactory.getProcessor("alipay");
-    processor.pay(666.0);
-  }
-}

com/study/demo4/TestTransport.java

@@ -1,22 +0,0 @@
-package com.study.demo4;
-
-public class TestTransport {
-  public static void main(String[] args) {
-    // 测试自行车配送
-    DeliveryFeeCalculator bike = new BikeDeliveryCalculator();
-    System.out.println("自行车配送 3km: ¥" + bike.calculateFee(3));
-    System.out.println("自行车配送 8km: ¥" + bike.calculateFee(8));
-
-    // 测试汽车配送
-    DeliveryFeeCalculator car = new CarDeliveryCalculator();
-    System.out.println("汽车配送 3km: ¥" + car.calculateFee(3));
-    System.out.println("汽车配送 8km: ¥" + car.calculateFee(8));
-
-    // 对比不同距离的费用
-    System.out.println("\n费用对比:");
-    for (int km = 1; km <= 10; km++) {
-      System.out.printf("%dkm: 自行车¥%.1f, 汽车¥%.1f%n",
-          km, bike.calculateFee(km), car.calculateFee(km));
-    }
-  }
-}

com/study/demo4/WechatPayment.java

@@ -1,9 +0,0 @@
-package com.study.demo4;
-
-class WechatPayment implements PaymentProcessor {
-  @Override
-  public boolean pay(double amount) {
-    System.out.println("微信支付: " + amount);
-    return true;
-  }
-}

com/study/demo5/DataIO.java

@@ -1,40 +0,0 @@
-package com.study.demo5;
-
-import java.io.*;
-
-public class DataIO {
-  public void writeConfig(String path) {
-    try (DataOutputStream dos = new DataOutputStream(
-        new FileOutputStream(path))) {
-
-      dos.writeUTF("李华"); // 用户名
-      dos.writeInt(25); // 年龄
-      dos.writeBoolean(true); // 是否启用
-      dos.writeDouble(1234.56); // 余额
-
-      System.out.println("配置写入成功: " + path);
-
-    } catch (IOException e) {
-      System.err.println("写入配置失败: " + e.getMessage());
-    }
-  }
-
-  public void readConfig(String path) {
-    try (DataInputStream dis = new DataInputStream(
-        new FileInputStream(path))) {
-
-      String username = dis.readUTF();
-      int age = dis.readInt();
-      boolean enabled = dis.readBoolean();
-      double balance = dis.readDouble();
-
-      System.out.println("用户名: " + username);
-      System.out.println("年龄: " + age);
-      System.out.println("是否启用: " + enabled);
-      System.out.println("余额: " + balance);
-
-    } catch (IOException e) {
-      System.err.println("读取配置失败: " + e.getMessage());
-    }
-  }
-}

com/study/demo5/FileCopy.java

@@ -1,20 +0,0 @@
-package com.study.demo5;
-
-import java.io.*;
-
-public class FileCopy {
-  public void copy(String source, String target) {
-    try (FileInputStream fis = new FileInputStream(source);
-        FileOutputStream fos = new FileOutputStream(target)) {
-      byte[] buffer = new byte[1024];
-      int bytesRead;
-      while ((bytesRead = fis.read(buffer)) != -1) {
-        fos.write(buffer, 0, bytesRead);
-      }
-    } catch (FileNotFoundException e) {
-      System.err.println("源文件未找到: " + e.getMessage());
-    } catch (IOException e) {
-      System.err.println("文件复制失败: " + e.getMessage());
-    }
-  }
-}

com/study/demo5/FileStat.java

@@ -1,25 +0,0 @@
-package com.study.demo5;
-
-import java.io.*;
-
-public class FileStat {
-  public long countBytes(String filePath) {
-    long totalBytes = 0;
-
-    try (FileInputStream fis = new FileInputStream(filePath)) {
-
-      byte[] buffer = new byte[1024];
-      int bytesRead;
-
-      while ((bytesRead = fis.read(buffer)) != -1) {
-        totalBytes += bytesRead;
-      }
-
-    } catch (IOException e) {
-      System.err.println("文件读取失败: " + e.getMessage());
-      return -1;
-    }
-
-    return totalBytes;
-  }
-}

com/study/demo5/Main.java

@@ -1,17 +0,0 @@
-package com.study.demo5;
-
- public class Main {
-    public static void main(String[] args) {
-        // 7.1 测试
-        FileCopy fc = new FileCopy();
-        fc.copy("source.txt", "target.txt");
-        // 7.2 测试
-        DataIO dataIO = new DataIO();
-        dataIO.writeConfig("config.bin");
-        dataIO.readConfig("config.bin");
-        // 7.3 测试
-        FileStat fs = new FileStat();
-        long size = fs.countBytes("test3.txt");
-        System.out.println("文件大小: " + size + " 字节");
-    }
-}

com/study/demo6/SumThread.java

@@ -1,52 +0,0 @@
-package com.study.demo6;
-
-public class SumThread {
-  static class PartSumTask implements Runnable {
-    private final int[] array;
-    private final int start;
-    private final int end;
-    public long result;
-
-    public PartSumTask(int[] array, int start, int end) {
-      this.array = array;
-      this.start = start;
-      this.end = end;
-    }
-
-    @Override
-    public void run() {
-      long sum = 0;
-      for (int i = start; i <= end; i++) {
-        sum += array[i];
-      }
-      result = sum;
-    }
-  }
-
-  public static void main(String[] args) throws InterruptedException {
-    int size = 1_000_000;
-    int[] array = new int[size];
-    for (int i = 0; i < size; i++) {
-      array[i] = i;
-    }
-
-    PartSumTask task1 = new PartSumTask(array, 0, 333_333);
-    PartSumTask task2 = new PartSumTask(array, 333_334, 666_666);
-    PartSumTask task3 = new PartSumTask(array, 666_667, 999_999);
-
-    Thread t1 = new Thread(task1);
-    Thread t2 = new Thread(task2);
-    Thread t3 = new Thread(task3);
-
-    t1.start();
-    t2.start();
-    t3.start();
-
-    t1.join();
-    t2.join();
-    t3.join();
-
-    long total = task1.result + task2.result + task3.result;
-    System.out.println("总和为：" + total);
-  }
-}

com/study/demo6/ThreadDemo1.java

@@ -1,20 +0,0 @@
-package com.study.demo6;
-
-public class ThreadDemo1 {
-  static class MyThread extends Thread {
-    @Override
-    public void run() {
-      for (int i = 1; i <= 5; i++) {
-        System.out.println("当前线程：" + getName() + "，输出次数 " + i);
-      }
-    }
-  }
-
-  public static void main(String[] args) {
-    MyThread s1 = new MyThread();
-    MyThread s2 = new MyThread();
-
-    s1.start();
-    s2.start();
-  }
-}

com/study/demo6/ThreadDemo2.java

@@ -1,22 +0,0 @@
-package com.study.demo6;
-
-public class ThreadDemo2 {
-  static class CountTask implements Runnable {
-    @Override
-    public void run() {
-      for (int i = 1; i <= 10; i++) {
-        System.out.println(Thread.currentThread().getName() + " 计数：" + i);
-        try {
-          Thread.sleep(500);
-        } catch (InterruptedException e) {
-          e.printStackTrace();
-        }
-      }
-    }
-  }
-
-  public static void main(String[] args) {
-    Thread t = new Thread(new CountTask(), "计数线程");
-    t.start();
-  }
-}

flake.nix

@@ -3,7 +3,7 @@
   inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
   outputs = { self, nixpkgs }:
   let
-    supportedSystems = [ "x86_64-linux" ];
+    supportedSystems = [ "x86_64-linux" "aarch64-linux" ];
     forEachSupportedSystem = f: nixpkgs.lib.genAttrs supportedSystems (system: f {
       pkgs = import nixpkgs { inherit self system; };
     });