Java - FileWriter Class

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This class inherits from the OutputStreamWriter class. The class is used for writing streams of characters.

This class has several constructors to create required objects.

Following syntax creates a FileWriter object given a File object.

FileWriter(File file) 

Following syntax creates a FileWriter object given a File object.

FileWriter(File file, boolean append) 

Following syntax creates a FileWriter object associated with a file descriptor.

FileWriter(FileDescriptor fd) 

Following syntax creates a FileWriter object given a file name.

FileWriter(String fileName) 

Following syntax creates a FileWriter object given a file name with a boolean indicating whether or not to append the data written.

FileWriter(String fileName, boolean append) 

Once you have FileWriter object in hand, then there is a list of helper methods, which can be used manipulate the files.

SNMethods with Description
1public void write(int c) throws IOException
Writes a single character.
2public void write(char [] c, int offset, int len)
Writes a portion of an array of characters starting from offset and with a length of len.
3public void write(String s, int offset, int len)
Write a portion of a String starting from offset and with a length of len.

Example:

Following is the example to demonstrate class:

import java.io.*;

public class FileRead{

   public static void main(String args[])throws IOException{

      File file = new File("Hello1.txt");
      // creates the file
      file.createNewFile();
      // creates a FileWriter Object
      FileWriter writer = new FileWriter(file); 
      // Writes the content to the file
      writer.write("This\n is\n an\n example\n"); 
      writer.flush();
      writer.close();

      //Creates a FileReader Object
      FileReader fr = new FileReader(file); 
      char [] a = new char[50];
      fr.read(a); // reads the content to the array
      for(char c : a)
          System.out.print(c); //prints the characters one by one
      fr.close();
   }
}

This would produce the following result:

This
is
an
example



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