How to load a text file from classpath to a String[] in Java

Question

Im trying to read the content from a text file to a String. In the Netbeans IDE everthing works perfectly, but if I compile nothing works.

Here's my code:

private String[] getSplashes(String Name) {
    String[] sp = null;
    try {
        String content = new Scanner(new File(getClass().getResource(Name).getFile())).useDelimiter("\\Z").next();
        sp = content.split(";");
    } catch (IOException ex) {
    }
    return sp;
}

Here's the exception I get:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
    at jumpover.MenuDrawing.getRandomSplash(MenuDrawing.java:51)
    at jumpover.MenuDrawing.<init>(MenuDrawing.java:47)
    at jumpover.JOFrame.<init>(JOFrame.java:18)
    at jumpover.JOFrame.lambda$main$0(JOFrame.java:46)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

I don't know what I am doing wrong!

*In the Netbeans IDE everthing works perfectly, but if I compile nothing works.* you mean when you try to compile externally using `javac` command ? — Anand Undavia, Mar 08 '17 at 14:13
Possible duplicate of [What is simplest way to read a file into String?](http://stackoverflow.com/questions/3402735/what-is-simplest-way-to-read-a-file-into-string) — Pushkarraj Pujari, Mar 08 '17 at 14:13

score 4 · Accepted Answer · answered Mar 08 '17 at 14:12

4

Use getClass().getResourceAsStream(Name)

instead of

new File(getClass().getResource(Name).getFile())

In the end you get:

String content = new Scanner(getClass().getResourceAsStream(Name)).useDelimiter("\\Z").next();

Accessing a resource as a file is always a bad idea as the resource can be inside of a JAR file and therefore not directly accessible as common file. However if you access it as stream you can always access it.

answered Mar 08 '17 at 14:12

Robert

39,162
17
99
152

1

Maybe a good time to link to documentation : http://stackoverflow.com/documentation/java/2433/resources-on-classpath#t=20170308141832789658 and/or http://stackoverflow.com/documentation/java/3720/the-classpath/14224/load-a-resource-from-the-classpath#t=201703081420243516318 – GPI Mar 08 '17 at 14:20
Thank you Robert! Works perfectly! :) – amsjntz Mar 08 '17 at 16:03

score 1 · Answer 2 · answered Mar 08 '17 at 14:38

1

if you generate a jar file you have to put the txt file in the same folder as jar's folder.

answered Mar 08 '17 at 14:38

The Appsolit

89
10

How to load a text file from classpath to a String[] in Java

2 Answers2