Duvida em File...fr.read(in)

package certificacao.licão_8_7;

import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

class Writer2 {
	  public static void main(String [] args) {
	    char[] in = new char[50];           // to store input
	    int size = 0;
	    try {
	      File file = new File(             // just an object
	                  "fileWrite2.txt");
	      FileWriter fw =
	                 new FileWriter(file);  // create an actual file
	                                        // & a FileWriter obj

	      fw.write("paulo\ncristina\nmaria\nsilvio\nboneca\nprincesa")  ;                                // the file
	      fw.flush();                       // flush before closing
	      fw.close();                       // close file when done

	      FileReader fr =  new FileReader(file);  // create a FileReader
	                                        // object
	      size = fr.read(in);               // read the whole file!
	      System.out.print(size + " ");     // how many bytes read
	      for(char c : in)                  // print the array
	        System.out.print(c);
	      fr.close();                       // again, always close }
	    } catch(IOException  e) { }
	  }
	}

resultado:
43 paulo
cristina
maria
silvio
boneca
princesa