Need help filling in the areas, unsure of how to do the code, JAVA. I\'ve highli

Question

 Need help filling in the areas, unsure of how to do the code, JAVA. I've highlited what needs completing. 

  /**    LineNumberer is the first example program in Chapter 11.    It reads a file and prepends each line with a line number.    For example, if the following is the input file:  Mary had a little lamb whose fleece was white as snow. Every where that Mary went, the lamb was sure to go.     Then the following is the output file (ignoring the // comment symbols) */  //    /* 1 */ Mary had a little lamb //    /* 2 */ whose fleece was white as snow. //    /* 3 */ Every where that Mary went, //    /* 4 */ the lamb was sure to go. import java.io.File ; import java.io.FileNotFoundException ; import java.io.PrintWriter ; import java.util.Scanner ;  public class LineNumberer {     //-----------Start below here. To do: approximate lines of code = 1     // 1. public static void main( ... so that file IO is possible without catching a possible FileNotFoundException          //-----------------End here. Please do not remove this comment. Reminder: no changes outside the todo regions.     {         File infile = null ;         //-----------Start below here. To do: approximate lines of code = 1         // 2. set infile to the file input1                  //-----------------End here. Please do not remove this comment. Reminder: no changes outside the todo regions.         Scanner scanner = new Scanner(infile) ;         PrintWriter pw = new PrintWriter("output1") ;         int lineNumber = 1 ;         //-----------Start below here. To do: approximate lines of code = 4         // 3-6. Write the while loop that goes through the input file and prints the output file line by line with the commented line numbers.                                                      //-----------------End here. Please do not remove this comment. Reminder: no changes outside the todo regions.         long length1 = infile.length() ;         pw.close() ;         scanner.close() ;         //This next part is just to show what is in the output file         infile = new File("output1") ;         scanner = new Scanner(infile) ;         while (scanner.hasNextLine()) {             System.out.println(scanner.nextLine()) ;         }         long length2 = infile.length() ;         if (length2 <= length1)             System.out.println("Error: You have to print to the given output file.") ;     } } 

Explanation / Answer

inputfile.txt

Mary had a little lamb
whose fleece was white as snow.
Every where that Mary went,
the lamb was sure to go.

_______________

LineNumberer.java

/**

LineNumberer is the first example program in Chapter 11.

It reads a file and prepends each line with a line number.

For example, if the following is the input file:

Mary had a little lamb

whose fleece was white as snow.

Every where that Mary went,

the lamb was sure to go.

Then the following is the output file (ignoring the // comment symbols)

*/

// /* 1 */ Mary had a little lamb

// /* 2 */ whose fleece was white as snow.

// /* 3 */ Every where that Mary went,

// /* 4 */ the lamb was sure to go.

import java.io.File ;

import java.io.FileNotFoundException ;

import java.io.PrintWriter ;

import java.util.Scanner ;

public class LineNumberer

{

//-----------Start below here. To do: approximate lines of code = 1

// 1. public static void main( ... so that file IO is possible without catching a possible FileNotFoundException

public static void main(String args[]) throws FileNotFoundException

//-----------------End here. Please do not remove this comment. Reminder: no changes outside the todo regions.

{

File infile = null ;

//-----------Start below here. To do: approximate lines of code = 1

// 2. set infile to the file input1

infile=new File("inputfile.txt");

//-----------------End here. Please do not remove this comment. Reminder: no changes outside the todo regions.

Scanner scanner = new Scanner(infile) ;

PrintWriter pw = new PrintWriter("output1") ;

int lineNumber = 1 ;

//-----------Start below here. To do: approximate lines of code = 4

// 3-6. Write the while loop that goes through the input file and prints the output file line by line with the commented line numbers.

while(scanner.hasNext())

{

pw.write("/* "+lineNumber+" */ "+scanner.nextLine()+" ");

lineNumber++;

}

//-----------------End here. Please do not remove this comment. Reminder: no changes outside the todo regions.

long length1 = infile.length() ;

pw.close() ;

scanner.close() ;

//This next part is just to show what is in the output file

infile = new File("output1") ;

scanner = new Scanner(infile) ;

while (scanner.hasNextLine()) {

System.out.println(scanner.nextLine()) ;

}

long length2 = infile.length() ;

if (length2 <= length1)

System.out.println("Error: You have to print to the given output file.") ;

}

}

________________

Output:

/* 1 */ Mary had a little lamb
/* 2 */ whose fleece was white as snow.
/* 3 */ Every where that Mary went,
/* 4 */ the lamb was sure to go.

________________

Output1.txt

/* 1 */ Mary had a little lamb
/* 2 */ whose fleece was white as snow.
/* 3 */ Every where that Mary went,
/* 4 */ the lamb was sure to go.

________________Thank You

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