Dateien lesen klappt nicht

[Flausch96]

Hallo, ich habe eine Funktion zum auslesen des Inhaltes einer Textdatei geschrieben. Jedoch klappt das nicht so ganz. Ich bekomme immer folgende Fehlermeldungen:


Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at start.<init>(start.java:21)
at main$1.actionPerformed(main.java:18)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(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$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.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)


und hier mein code:

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    public start() {
        File ordner = new File("C:\\ordner");
        ordner.mkdir();
        try {
            BufferedReader in = new BufferedReader(new FileReader("C://ordner//test.txt"));
            level = null;
            while ((text = in.readLine()) != null) {
                System.out.println("text: " + text);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }   
        if(text.equals("LOL")){
            System.out.println("klappt super");
        }
    }

[XHelp]

Zu dem Fehler: Nach der Schleife ist text null, da kannst du nicht .equals aufrufen.

Generell: Wenn du schon Code+Fehlermeldung postest, dann achte bitte darauf, dass du die Zeilen markierst, die in der Fehlermeldung stehen. Und du verwendest übrigens // in dem Pfad, was überflüssig ist: entweder \\ oder /

[Flausch96]

Danke, jetzt klappt es. Habe die if abfrage jetzt in die Schleife gepackt.