Java Unicode String is null?

Question

I want to print a box into the Java console using Unicode characters, but for some reason it gives me this runtime error:

--------------------Configuration: PacManGame - JDK version 1.7.0_25 <Default> - <Default>--------------------
Exception in thread "main" java.lang.NullPointerException
    at Scoreboard.genTopLine(Scoreboard.java:35)
    at Scoreboard.<init>(Scoreboard.java:17)
    at PacManGame.main(PacManGame.java:36)

Process interrupted by user.

code: http://pastebin.com/nuAsH857

Does anyone know what's wrong?

Have you tried to debug yor program? Which value is null iin line 35 of class Scoreboard? — Jens, May 31 '14 at 22:45
@Zavior Did you even read the code? I know it's null, but it's null even after I set it. — Aido, May 31 '14 at 22:52
@Jens Did you even read the code? I know it's null, but it's null even after I set it. — Aido, May 31 '14 at 22:52
"and how do I fix it". A debugger would have served you well here. — awksp, May 31 '14 at 22:54
@user3580294 You didn't look at my code either, did you? I set the variable, it shouldn't be null anymore. — Aido, May 31 '14 at 22:55
I wasn't talking about the variable. And yes, I did look at your code. — awksp, May 31 '14 at 22:56
Can you post some code which we could actually use to reproduce your problem? The only NPE I can get is the one from `System.console().writer()` because `System.console()` returns `null` if there is no console, like if application was executed with `javaw.exe` instead of `java.exe` (like most of IDEs does to run code). — Pshemo, May 31 '14 at 22:58
I saw it, that is why I said I got NPE on `System.console().writer()`. What I meant is some code with `main` method which we could use to get exactly same exception you are seeing. For now I can't reproduce your problem so will not be able to help you. — Pshemo, May 31 '14 at 23:00
Actually I used this code to create previously mentioned NPE. When I run it using `javaw.exe` console wasn't created so `System.console()` returned `null` (as expected). When I run id via `java.exe` it worked fine, but I am using Java 8 so that may be somehow relevant :/ — Pshemo, May 31 '14 at 23:30

score 0 · Answer 1 · edited May 23 '17 at 12:20

0

topline is actually NOT null - it's perfectly fine.
The problem is the use of System.console() which returns null (and hence you get NPE on .writer()).

Use System.out.println() instead and it'll work just fine.

An explanation as to why System.console() doesn't work in your IDE can be found here

edited May 23 '17 at 12:20

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answered May 31 '14 at 22:48

Nir Alfasi

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But when I do that the unicode prints incorrectly. – Aido May 31 '14 at 22:53
@AidanEdwards make sure that your IDE is set to use UTF-8. Go to "Settings | File Encodings" – Nir Alfasi May 31 '14 at 23:18
Do you know where it would be in JCreator? – Aido May 31 '14 at 23:19
@AidanEdwards nope... – Nir Alfasi May 31 '14 at 23:27
Another thing you can try: `byte[] utf8Bytes = topLine.getBytes("UTF8"); String topLine = new String(utf8Bytes, "UTF8");` and then print it using SOP. – Nir Alfasi May 31 '14 at 23:27
Still just prints ????????????????????. :( – Aido May 31 '14 at 23:31
Try running from command line. – Nir Alfasi May 31 '14 at 23:34
I've never done that before and can't seem to find a good tutorial on doing so. Could you link one? – Aido May 31 '14 at 23:44
Go to the folder that contains your java file (in command line) and run `javac Scoreboard.java` and then `java Scoreboard` – Nir Alfasi May 31 '14 at 23:50
It says it isn't a recodnized command – Aido May 31 '14 at 23:55
Google "how to set my classpath java" and the name of your operating-system – Nir Alfasi May 31 '14 at 23:56

Java Unicode String is null?

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