java 异常练习自定义异常

悠悠 2022-05-18 10:59 289阅读 0赞

## 自定义异常一般要继承Exception和RuntimeException 以及它们的子类，通过自定义异常更能细化异常的问题，帮助jvm和程序员更好的理解和分析代码 ##

# 创建自定义异常类 #

public class IllegleAgeException extends RuntimeException {
        //自定义异常类继承自运行时类（RuntimeException）
        //重写自定义类的构造方法
        //因为在继承时只有构造方法不会被直接继承
    	public IllegleAgeException() {
    		super();
    	}
    
    	public IllegleAgeException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {
    		super(message, cause, enableSuppression, writableStackTrace);
    	}
    
    	public IllegleAgeException(String message, Throwable cause) {
    		super(message, cause);
    	}
    
    	public IllegleAgeException(String message) {
    		super(message);
    	}
    
    	public IllegleAgeException(Throwable cause) {
    		super(cause);
    	}
    	
    }

# 创建一个Person类 #

public class Person {
    	private String name;
    	private int age;
    	public Person() {
    		super();
    		// TODO Auto-generated constructor stub
    	}
    	public Person(String name, int age) {
    		super();
    		this.name = name;
    		this.age = age;
    	}
    	@Override
    	public String toString() {
    		return "Person [name=" + name + ", age=" + age + "]";
    	}
    	public String getName() {
    		return name;
    	}
    	public void setName(String name) {
    		this.name = name;
    	}
    	public int getAge() {
    		return age;
    	}
    	public void setAge(int age) {
    		if(age >= 0 && age <= 250) {
    			this.age = age;
    		}else {
                //抛出自定义异常类
    			throw new IllegleAgeException("输入错误！年龄应大于0,小于250");
    		}
    	}
    	
    	
    	
    }

## 测试类 ##

public class Test {
    
    	public static void main(String[] args) {
    		try {
    			Person p = new Person();
    			p.setName("赵柳");
    			p.setAge(-987654);
    			System.out.println(p);
            //该异常未出现，不执行
    		}catch(ArithmeticException ae){
    			System.out.println("我难道没有重见天日的机会了？？？");
            //捕获到自定义异常，抛出自定义异常类
    		}catch (IllegleAgeException e) {
    			System.out.println("与你偶遇一场……见了一个异常！");
    		}
    	}
    
    }