JAVA CodeX精选实用代码示例

基于Java CodeX的实用代码

以下是基于Java CodeX的实用代码示例，涵盖基础语法、数据结构、算法及常见应用场景，按功能分类呈现：

---

基础语法示例

1. Hello World程序

public class HelloWorld {public static void main(String[] args) {System.out.println("Hello, World!");}
}

2. 变量与数据类型

int num = 10;
double pi = 3.14;
char letter = 'A';
boolean flag = true;

3. 条件语句

int age = 18;
if (age >= 18) {System.out.println("Adult");
} else {System.out.println("Minor");
}

4. 循环语句

for (int i = 0; i < 5; i++) {System.out.println("Iteration: " + i);
}

5. 方法定义与调用

public static int add(int a, int b) {return a + b;
}
// 调用：add(3, 5);

---

数据结构示例

6. 数组操作

int[] numbers = {1, 2, 3};
System.out.println(numbers[1]); // 输出2

7. ArrayList动态数组

ArrayList<String> list = new ArrayList<>();
list.add("Java");
list.remove(0);

8. HashMap键值对

HashMap<String, Integer> map = new HashMap<>();
map.put("Alice", 25);
int age = map.get("Alice");

9. LinkedList链表

LinkedList<Integer> linkedList = new LinkedList<>();
linkedList.add(10);
linkedList.removeFirst();

10. Stack栈

Stack<String> stack = new Stack<>();
stack.push("A");
String top = stack.pop();

---

字符串处理示例

11. 字符串拼接

String s1 = "Hello";
String s2 = s1.concat(" Java");

12. 字符串分割

String str = "a,b,c";
String[] parts = str.split(",");

13. 字符串反转

StringBuilder sb = new StringBuilder("Java");
String reversed = sb.reverse().toString();

14. 字符串查找

String text = "CodeX";
int index = text.indexOf("X"); // 返回4

15. 格式化字符串

String formatted = Strin