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POReading from two files and then combining them and writing to a third, java
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  1. POReading from two files and then combining them and writing to a third, java
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    copied!<p>I have to write a program that reads from two files that each have a list of names and IDs that are both already in alphabetical order based on last name. The program is then suppose to create a third file that the user names that contains a complete list of all the names and IDs from the two programs and puts them in alphabetical order. The format of the files are as such--</p> <p>Last name,First name<br> ID(ex.rbb091020)<br> Last name, First name<br> ID</p> <p>My program reads the two files, and creates a third, but for some reason, it doesn't write anything to the third file, and the file is left blank. What can I do to fix this?</p> <p>Here is my code...</p> <pre><code>import java.io.*; import java.util.Scanner; public class Combine_Files { public static void main(String[]args) throws IOException { String filename1 = ""; String filename2 = ""; String combinedFileName = ""; String response = ""; String nextName1 = ""; String nextName2 = ""; String nextIDNumber1 = ""; String nextIDNumber2 = ""; boolean okToOverwrite = false; Scanner keyboard = new Scanner(System.in); System.out.println("What is the name of the first file?"); filename1 = keyboard.nextLine(); File file1 = new File(filename1); if (!file1.exists()) { System.out.println(file1 + " does not exist.\nTerminating Program."); System.exit(0); } System.out.println("What is the name of the second file?"); filename2 = keyboard.nextLine(); File file2 = new File (filename2); if (!file2.exists()) { System.out.println(file2 + " does not exist.\nTerminating Program."); System.exit(0); } System.out.println("What is the name of the file that you wish to create?"); combinedFileName = keyboard.nextLine(); File combinedFile = new File (combinedFileName); while (combinedFile.exists() &amp;&amp; !okToOverwrite) { System.out.println("\nError, a file named " + combinedFileName + " already exists." + "\nWould you like to overwrite this file?" + "\nEnter Y for Yes or N for No."); response = keyboard.nextLine(); // Add input validation on response if (response.equalsIgnoreCase("Y")) { okToOverwrite = true; } else { System.out.println("Enter a new filename."); combinedFileName = keyboard.nextLine(); combinedFile = new File(combinedFileName); } } if (file1.exists() &amp;&amp; file2.exists()) { Scanner list1 = new Scanner(file1); Scanner list2 = new Scanner(file2); PrintWriter outputFile = new PrintWriter(combinedFile); while (list1.hasNext() &amp;&amp; list2.hasNext()) { nextName1 = list1.nextLine(); nextName2 = list2.nextLine(); if(nextName1.compareToIgnoreCase(nextName2) &lt;0) { outputFile.print(nextName1); nextName1 = list1.nextLine(); outputFile.print(nextName1); } else if(nextName1.compareToIgnoreCase(nextName2) &gt;0) { outputFile.println(nextName2); nextName2 = list2.nextLine(); outputFile.println(nextName2); } else { outputFile.println(nextName1); nextName1 = list1.nextLine(); outputFile.println(nextName1); outputFile.println(nextName2); nextName2 = list2.nextLine(); outputFile.println(nextName2); } } while (list1.hasNext() &amp;&amp; !list2.hasNext()) { outputFile.println(nextName1); } while (list2.hasNext() &amp;&amp; !list1.hasNext()) { outputFile.println(nextName2); } outputFile.close(); } } } </code></pre>
 

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