testex.java

这是上学堂马士兵老师教授的javaSE的所有源代码

import java.io.*;

public class TestEx {
	public static void main(String[] args) {
		
		try {
			new TestEx().f2();
		} catch (IOException e) {
			e.printStackTrace();
		}
		
		/*
		int[] arr = {1, 2, 3};
		System.out.println(arr[2]);
		try {
			System.out.println(2/0);
		} catch (ArithmeticException e) {
			System.out.println("系统正在维护,请与管理员联系");
			e.printStackTrace();
		}
		*/
		
		//TestEx te = new TestEx();
		//te.m(0);
		
		/*
		try {
			new TestEx().m(0);
		} catch (ArithmeticException ae) {
			ae.printStackTrace();
			System.out.println("出错了");
		}
		*/
		
		
		FileInputStream in = null;
		
    try {
        in = new FileInputStream("myfile.txt");
        int b;
        b = in.read();
        while (b != -1) {
            System.out.print((char) b);
            b = in.read();
        }
    } catch (IOException e) {
      System.out.println(e.getMessage());
     	
    } catch (FileNotFoundException e) {
    	e.printStackTrace(); 
      
    } finally {
    	try {
      	in.close();
      } catch (IOException e) {
      	e.printStackTrace();
      }
    }
    
 
	}
	
	void m(int i) throws ArithmeticException {
		if(i==0) 
			throw new ArithmeticException("被除数为0");
	}
	
	void f() throws FileNotFoundException , IOException {
		FileInputStream in = new FileInputStream("myfile.txt");
    int b;
    b = in.read();
    while (b != -1) {
        System.out.print((char) b);
        b = in.read();
    }
	}
	
	void f2() throws IOException {
		/*
		try {
			f();
		} catch (FileNotFoundException e) {
			System.out.println(e.getMessage());
		} catch (IOException e) {
			e.printStackTrace();
		}
		*/
		f();
	}
	
}