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POException in thread "main" java.lang.NullPointerException cann't write to a class
 

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    <p><strong>So I have this code :</strong></p> <pre><code>package Firstpack; import java.io.*; import java.util.*; public class Main { public static void menu() { System.out.println("Welcome"); System.out.println("1. Add a record "); System.out.println("2. See all records "); System.out.println("3. See a category"); System.out.println("4. Total spend(Year)"); System.out.println("5. Spend in a month"); System.out.println("6. Chose by index"); System.out.println("7. Exit "); System.out.print("&gt;"); Scanner in = new Scanner(System.in); int enteredInt = in.nextInt(); in.close(); switch (enteredInt) { case 1: recording(); break; case 2: System.out.print(" You have chosen -&gt; See all records"); break; case 3: System.out.print(" You have chosen -&gt; See a category"); break; case 4: System.out.print(" You have chosen -&gt; Total spend(Year)"); break; case 5: System.out.print(" You have chosen -&gt; Spend in a month"); break; case 6: System.out.print(" You have chosen -&gt; Chose by index"); break; case 7: System.out.print(" Bye! "); break; default: menu(); } } public static void recording() { System.out.println(" You have chosen -&gt; Add a record"); record rec = new record(); Scanner in = new Scanner(System.in); System.out.print("Enter Amount &gt; "); rec.amount = in.nextDouble(); System.out.print("Enter Category &gt; "); rec.category = in.next(); System.out.print("Enter Details &gt; "); rec.details = in.next(); try { FileWriter fw = new FileWriter("findme.txt"); BufferedWriter bw = new BufferedWriter(fw); bw.write(String.valueOf(rec.amount)); bw.write(rec.category); bw.write(rec.details); bw.close(); fw.close(); } catch (IOException e) { e.printStackTrace(); } } public static void main(String[] args) { menu(); } } </code></pre> <p>And it throws me this:</p> <pre><code>Exception in thread "main" java.lang.NullPointerException at java.io.Writer.write(Unknown Source) at Firstpack.Main.recording(Main.java:68) at Firstpack.Main.menu(Main.java:25) at Firstpack.Main.main(Main.java:82) </code></pre> <p>And I have no idea how to solve this. What is wrong here? </p>
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    3. COConsider using `java.io.Console` instead of `Scanner`.
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