Program 20.5: Print files and line number them

import java.io.FileInputStream;
import java.io.DataInputStream;
import java.io.LineNumberInputStream;
import java.io.IOException;


class lcat  {

  public static void main (String args[]) {
  
    String thisLine;

    //Loop across the arguments
    for (int i=0; i < args.length; i++) {
 
      //Open the file for reading
      try {
        FileInputStream fin =  new FileInputStream(args[i]);

       // chain the DataInputStream to a LineNumberInputStream
       LineNumberInputStream lnis = new 
         LineNumberInputStream(fin);

       // now turn the FileInputStream into a DataInputStream
       try {
         DataInputStream myInput = new DataInputStream(lnis);
         try {
           while ((thisLine = myInput.readLine()) != null) {  
             System.out.println(lnis.getLineNumber() + ": " + 
               thisLine);
           } // while loop ends here
         }
        catch (Exception e) {
       System.err.println("Error: " + e);
      }
    } // end try
    catch (Exception e) {
      System.err.println("Error: " + e);
    }
  
   } // end try
   catch (Exception e) {
     System.err.println("failed to open file " + args[i]);
     System.err.println("Error: " + e);
   }
  } // for ends here
  
  } // main ends here

}

% java lcat lcat.java
1: import java.io.FileInputStream;
2: import java.io.DataInputStream;
3: import java.io.LineNumberInputStream;
4:
5:
6: class lcat  {
7:
8:   public static void main (String args[]) {
9:
10:     String thisLine;
11:
12:     //Loop across the arguments
13:     for (int i=0; i < args.length; i++) {
14:
15:       //Open the file for reading
16:       try {