java IO文件操作

一些范例：

1.读写

try{
    FileInputStream in=new FileInputStream("count.txt");
    DataInputStream dataIn=new DataInputStream(in);
    number=dataIn.readInt();
    number++;
    in.close();
    dataIn.close();
}
catch(FileNotFoundException e){ 

    number++;

    try {FileOutputStream out=new
    FileOutputStream("count.txt");
    DataOutputStream dataOut=new
    DataOutputStream(out);
    dataOut.writeInt(number);
    out.close();dataOut.close();
}
catch(IOException ee){}
}
catch(IOException ee)
{
}
}
else{
    number++;
try{
    FileOutputStream out=new FileOutputStream("count.txt");
    DataOutputStream dataOut=new DataOutputStream(out);
    dataOut.writeInt(number);
    out.close();dataOut.close();
}
    catch(FileNotFoundException e){}
    catch(IOException e){}
 }
}

2 按行读

 try{
File f=new File("D:/test","A.txt");
FileReader in=new FileReader(f);
BufferedReader buffer=new BufferedReader(in);
String s=null;
while((s=buffer.readLine())!=null)
{ out.print(s+"<BR>");
}
in.close();buffer.close();
}
catch(IOException ee)
{out.print(" 文件不存在");}