java-basic-study-01 java的异常讨论01

版权声明：本文为博主原创文章，经博主允许，可自由共享，尽量不要用于商业用途。 https://blog.csdn.net/matrixbbs/article/details/88303361

1 不处理异常

package cc.zfh.javaBasic;

import java.util.Scanner;

public class Average {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner console = new Scanner(System.in);
		double sum = 0;
		int count = 0;
		
		while (true) {
			int number = console.nextInt();
			if (number == 0) {
				break;
			}
			sum += number;
			count++;
		}
		System.out.printf("average of numbers is %.2f%n",sum/count);
	}

}

2 捕获异常

package cc.zfh.javaBasic;

import java.util.InputMismatchException;
import java.util.Scanner;

public class Average2 {

	public static void main(String[] args) {
		try {
			Scanner console = new Scanner(System.in);
			double sum = 0;
			int count = 0;
			while (true) {
				int number = console.nextInt();
				if (number == 0) {
					break;
				}
				sum += number;
				count++;
			}
			System.out.printf("average of numbers is %.2f%n",sum/count);
		} catch (InputMismatchException ex) {
			// TODO: handle exception
			System.out.println("必须输入整数");
		}
	}
}

3 只在业务处理处捕获异常
package cc.zfh.javaBasic;

import java.util.InputMismatchException;
import java.util.Scanner;

public class Average3 {

public static void main(String[] args) {
	Scanner console = new Scanner(System.in);
	double sum = 0;
	int count = 0;
	while (true) {
		try {
			int number = console.nextInt();
			if (number == 0) {
				break;
			}
			sum += number;
			count++;
		} catch (InputMismatchException ex) {
			// TODO: handle exception
			System.out.printf("略过非整数输入 %s%n",console.nextInt());
		}
	}
	System.out.printf("average of numbers is %.2f%n",sum/count);
}

}