一般在操作IO時(shí)異常的處理原則

package cn.itcast.exception;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.management.RuntimeErrorException;

/*
 IO異常應(yīng)該如何處理: 
 
 */
public class Demo1 {

    public static void main(String[] args) {
        readTest();
    }
    
    
    //拷貝圖片
    public static void copyImage(){
        FileInputStream fileInputStream = null;
        FileOutputStream fileOutputStream = null;
        try{
            //找到目標(biāo)文件
            File inFile = new File("F:\\美女\\1.jpg");
            File outFile = new File("F:\\拷貝.jpg");
            //建立數(shù)據(jù)的輸入輸出通道
            fileInputStream = new FileInputStream(inFile);
            fileOutputStream = new FileOutputStream(outFile);
            //建立緩沖字節(jié)數(shù)組猫态，邊讀邊寫(xiě)
            byte[] buf = new byte[1024];
            int length = 0 ; 
            while((length = fileInputStream.read(buf))!=-1){
                fileOutputStream.write(buf,0,length);
            }
        }catch(IOException e){
            System.out.println("拷貝出錯(cuò)了...");
            throw new RuntimeException(e);
        //關(guān)閉資源的原則： 先開(kāi)后關(guān)， 后開(kāi)先關(guān)遭庶。
        }finally{
            try{
                if(fileOutputStream!=null){
                    //關(guān)閉資源
                    fileOutputStream.close();
                }
            }catch(IOException e){
                throw new RuntimeException(e);
            }finally{
                try{
                    if(fileInputStream!=null){
                        fileInputStream.close();
                    }
                }catch(IOException e){
                    throw new RuntimeException(e);
                }
            }
        }
        
        
    }
    
    
    
    public static void readTest() {
        FileInputStream fileInputStream = null;
        try{
            File file = new File("F:\\a.txt");
            //建立文件的輸入流通道
            fileInputStream = new FileInputStream(file);
            //建立緩沖字節(jié)數(shù)組讀取文件數(shù)據(jù)
            byte[] buf = new byte[1024];
            int length = 0 ; //記錄本次讀取的字節(jié)個(gè)數(shù)
            //讀取文件的數(shù)據(jù)
            while((length = fileInputStream.read(buf))!=-1){
                System.out.println(new String(buf,0,length));
            }
        }catch(IOException e){
            //如何處理???
            System.out.println("讀取文件出錯(cuò)...");
            throw  new RuntimeException(e);  // 把真正的異常原因包裝到RuntimeException中然后再拋出慎菲。 （糖衣炮彈）
            
        }finally{
            try{
                //關(guān)閉資源()
                if(fileInputStream!=null){
                    fileInputStream.close();        
                    System.out.println("關(guān)閉資源成功...");
                }
            }catch(IOException e){
                System.out.println("關(guān)閉資源失敗...");
                throw  new RuntimeException(e);
            }
        }
    }
    
}