FileInputStream和FileOutputStream应用实例

复制文件FileStreamDemo.java的内容至文件file.txt文件,并显示输出 file.txt文件内容

 

package sky;

import java.io.*;

public class FileStreamDemo...{
    public static void main(String[] args)...{
        try...{
            byte[] buffer=new byte[1024];
            //源文件
            FileInputStream fis=new FileInputStream(new File("FileStreamDemo.java"));
            //目的文件
            FileOutputStream fos=new FileOutputStream(new File("file.txt"));
            System.out.println("复制文件: "+fis.available()+"字节");
            while(true)...{
                //复制小于1024的数据
                if(fis.available()<1024)...{
                    int remain=-1;
                    while((remain=fis.read())!=-1)...{
                        fos.write(remain);
                    }
                    break;
                }
                //复制大于1024的数据
                else...{
                    fis.read(buffer);
                    fos.write(buffer);
                }
            }
            fis.close();
            fos.close();
            System.out.println("复制完成");
        }catch(ArrayIndexOutOfBoundsException e)...{
            System.out.println("using: java FileSreamDemo src des");
            e.printStackTrace();
        }catch(IOException e)...{
            e.printStackTrace();
        }
        
        //输出file.txt文件的内容
        System.out.println("***********************");
        System.out.println("输出file.txt文件内容");
        try...{            
            FileInputStream fs=new FileInputStream(new File("file.txt"));
            byte[] buf=new byte[fs.available()];
            fs.read(buf);
            String str=new String(buf);
            System.out.println(str);
        }catch(ArrayIndexOutOfBoundsException e)...{
            System.out.println("using: java FileSreamDemo src des");
            e.printStackTrace();
        }catch(IOException e)...{
            e.printStackTrace();
        }
        System.out.println();
    }
}