Java基础-常见异常

package com.hspedu.exception_;

public class Course446 {
    public static void main(String[] args) {
        // 常见的运行异常5种

        // 空指针异常
        try {
//            String name = "韩顺平教育";
            String name = null;
            System.out.println("name.length: " + name.length());
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e.getMessage());
        }

        System.out.println("=========================================");
        // 数组越界异常
        int[] arr = {1, 2, 4};
        try {
            for (int i = 0; i <= arr.length; i++) {
                System.out.println(arr[i]);
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("错误信息：" + e.getMessage());
        }

        System.out.println("=========================================");
        // 类型转换异常
        A b = new B();
        B b2 = (B) b;   // 正确
        try {
            C c2 = (C) b;   // 错误
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println(e.getMessage());
        }

        System.out.println("=========================================");
        // 数字格式不正确异常
        try {
            String name = "韩顺平教育";
            int num = Integer.parseInt(name);
            System.out.println("num: " + num);
        } catch (NumberFormatException e) {
            e.printStackTrace();
            System.out.println(e.getMessage());
        }
    }
}

class A {
}

class B extends A {
}

class C extends A {
}