IO stream Common Errors and io Common Errors

IO stream Common Errors and io Common Errors

Requirement: use an IO stream to copy the content of a file to another file.

The file "good boy.txt" is located in the root directory of drive D. Copy the content of this file to c: \ myFile.txt.

Code:

Import java. io .*;

Public classInputAndOutputFile {

Public static void main (String [] args ){

FileInputStream FCM = null;

FileOutPutStream fos = null;

Try {// 1. Create an input stream object and read the D:/good boy.txt File

FCM = new FileInputStream ("D:/good boy.txt ");

// 2. Create an output stream object

Fos = new FileOutputStream ("C:/myFile.txt", true );

// 3. Create a transfer station array to store the content read each time

Byte [] words = new byte [1024];

// 4. Implement File Read and Write Through Loop

Inte len =-1;

While (len = FS. read (words ))! =-1 ){

Fos. write (words, 0, len );

}

// 5 forcibly clear the buffer

Fos. flush ();

System. out. println ("the copy is complete. Please check the file! ");

} Catch (FileNotFoundExcepton e ){

E. printStackTrace ();

} Catch (IOException e ){

E. printStackTrace ();

} Finally {
// 6. Close the stream

Try {

FCM. close ();

Fos. close ();

} Catch (IOException e ){

E. printStackTrace ();

}

}

}

Errors often occur when while LOOP writing:

Error code:

While (FCM. read ())! =-1) {// The error is here: At this time, the first read/write has been implemented for the FIPs. read (); so the characters cached in words are less than the first one, leading to a result error.
FS. read (words); // read the file

Fos. write (words, 0, words. length); // write a file

}