Apakah tujuan kaedah flush() dalam kelas BufferedWriter?

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
public class BufferedWriterExample {
   public static void main(String args[]) throws IOException {
      //Instantiating the OutputStreamWriter class
      OutputStreamWriter out = new OutputStreamWriter(System.out);
      //Instantiating the BufferedWriter
      BufferedWriter writer = new BufferedWriter(out);
      //Writing data to the console
      writer.write("Hello welcome to Tutorialspoint");
   }
}

import java.io.BufferedWriter;
import java.io.IOException;
import java.io.OutputStreamWriter;
public class BufferedWriterExample {
   public static void main(String args[]) throws IOException {
      //Instantiating the OutputStreamWriter class
      OutputStreamWriter out = new OutputStreamWriter(System.out);
      //Instantiating the BufferedWriter
      BufferedWriter writer = new BufferedWriter(out);
      //Writing data to the console
      writer.write("Hello welcome to Tutorialspoint");
      writer.flush();
   }
}

Hello welcome to Tutorialspoint