Source of FileReadChars.java


  1: import java.util.Scanner;
  2: import java.io.FileReader;
  3: import java.io.IOException;

  5: public class FileReadChars {
  6:    public static void main(String[] args) {
  7:       Scanner scnr = new Scanner(System.in);
  8:       FileReader fileReader = null;     // FileReader for reading chars
  9:       String fileName;                  // User defined file name
 10:       int charRead;                     // Data read from file

 12:       charRead = 0;

 14:       // Get file name from user
 15:       System.out.print("Enter a valid file name: ");
 16:       fileName = scnr.next();

 18:       try {
 19:          // Prompt user for input
 20:          System.out.println("Opening file " + fileName + ".");
 21:          fileReader = new FileReader(fileName); // May throw FileNotFoundException

 23:          // Use file input stream
 24:          System.out.print("Reading character values: ");
 25:          while (charRead != -1) {             // -1 means end of file has been reached
 26:             charRead = fileReader.read(); // May throw IOException
 27:             System.out.print(charRead + " ");
 28:          }
 29:       } catch (IOException excpt) {
 30:          System.out.println("Caught IOException: " + excpt.getMessage());
 31:       }

 33:       // Done with file, so try to close it
 34:       try {
 35:          if (fileReader != null) {
 36:             System.out.println("\nClosing file " + fileName + ".");
 37:          }
 38:       } catch (IOException excpt) {
 39:          System.out.println("Caught IOException: " + excpt.getMessage());
 40:       }
 41:       fileReader.close(); // close() may throw IOException if fails
 42:    }
 43: }