I/O in Java (2)

I/O in Java (2)

1. Reading and Writing large files

// Step 1: import the class;

// 1G = 1024*1024*1024

Import java. io .*;

Class Test {

Public static void main (String args []) {

// Declare the input stream application

FileInputStream FCM = null;

// Declare the reference of the output stream

FileOutputStream fos = null;

Try {

// Declare the object of the input stream

FCM = new FileInputStream ("e:/src/from.txt ");

// Declaration indicates the object of the output stream

Fos = new FileOutputStream ("e:/src/to.txt ");

// Generate a byte array

Byte [] buffer = new byte [1024];

While (){

// Call the read method of the input stream object to read data

Int temp = FCM. read (buffer, 0, buffer. length );

If (temp =-1 ){

Break;

}

Fos. write (buffer, 0, temp );

}

}

Catch (Exception e ){

System. out. println (e );

}

Finally {

Try {

FCM. close ();

Fos. close ();

}

Catch (Exception e ){

System. out. println (e );

}

}

}

}

2. How to Use the livestream

// Delimiter stream: When a file is read and written, it is based on characters.

// Byte input stream: Reader <------ FileReader

// In read (char [], int off, int len)

// Byte output stream: Writer <------ FileWriter

// Void write (char [], int off, int len)

// Read and write abcde

Import java. io .*;

Public class TestChar {

Public static void main (String arg []) {

FileReader fr = null;

FileWriter fe = null;

Try {

Fr = new FileReader ("e:/src/from.txt ");

Fe = new FileWriter ("e:/src/to.txt ");

Char [] buffer = new char [100];

Int temp = fr. read (buffer, 0, buffer. lenfth );

Fw. write (buffer, 0, temp );

}

Catch (Exception e ){

System. out. println (e );

}

Finally {

Try {

Fr. close ();

Fe. close ();

}

Catch (Exception e ){

System. out. println (e );

}

}

}

}