Source of FileReadChars2.java


  1: //FileReadChars2.java

  3: import java.util.Scanner;
  4: import java.io.FileReader;
  5: import java.io.IOException;

  7: public class FileReadChars2
  8: {
  9:     public static void main(String[] args)
 10:     {
 11:         Scanner scnr = new Scanner(System.in);
 12:         FileReader fileReader = null; // FileReader for reading chars
 13:         String fileName; // User defined file name
 14:         int charRead;    // Data read from file

 16:         charRead = 0;

 18:         // Get file name from user
 19:         System.out.print("Enter a valid file name: ");
 20:         fileName = scnr.next();

 22:         try
 23:         {
 24:             // Prompt user for input
 25:             System.out.println("Opening file " + fileName + ".");
 26:             // May throw FileNotFoundException
 27:             fileReader = new FileReader(fileName);

 29:             // Use file input stream
 30:             System.out.print("Reading character values: ");
 31:             while (charRead != -1) // -1 means end of file has been reached
 32:             {
 33:                 charRead = fileReader.read(); // May throw IOException
 34:                 System.out.print(charRead + " ");
 35:             }
 36:         }
 37:         catch (IOException excpt)
 38:         {
 39:             System.out.println("Caught IOException: " + excpt.getMessage());
 40:         }

 42:         // Done with file, so try to close it
 43:         try
 44:         {
 45:             if (fileReader != null)
 46:             {
 47:                 System.out.println("\nClosing file " + fileName + ".");
 48:             }
 49:         }
 50:         catch (IOException excpt)
 51:         {
 52:             System.out.println("Caught IOException: " + excpt.getMessage());
 53:         }
 54:         fileReader.close(); // close() may throw IOException if fails
 55:     }
 56: }