Hi, bin ganz neu in Java, need help!
Mein Quellcode:
[Java]currentPost.edit()
import java.awt.*;
import java.awt.event.*;
/**
*
* Beschreibung
*
* @version 1.0 vom 16.10.2009
* @author
*/
public class GUIBurchrechner extends Frame {
// Anfang Attribute
private TextField textZaehler1 = new TextField();
private TextField textField1 = new TextField();
private TextField textZaehler2 = new TextField();
private TextField textNenner2 = new TextField();
private Button multiplizieren = new Button();
private Button addieren = new Button();
private Button subtrahieren = new Button();
private Button dividieren = new Button();
private Label Bruch1 = new Label();
private Label labelBruch2 = new Label();
private TextField textErg1 = new TextField();
private TextField textErg2 = new TextField();
private Label labelErgebnis = new Label();
private Bruchrechner Rechner = new Bruchrechner();
private Bruch B1, B2, BErg;
// Ende Attribute
public GUIBurchrechner(String title) {
// Frame-Initialisierung
super(title);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent evt) { System.exit(0); }
});
int frameWidth = 284;
int frameHeight = 276;
setSize(frameWidth, frameHeight);
Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
int x = (d.width - getSize().width) / 2;
int y = (d.height - getSize().height) / 2;
setLocation(x, y);
Panel cp = new Panel(null);
add(cp);
// Anfang Komponenten
textZaehler1.setBounds(48, 48, 25, 24);
textZaehler1.setText("");
cp.add(textZaehler1);
textField1.setBounds(48, 80, 25, 24);
textField1.setText("");
cp.add(textField1);
textZaehler2.setBounds(104, 48, 25, 24);
textZaehler2.setText("");
cp.add(textZaehler2);
textNenner2.setBounds(104, 80, 25, 24);
textNenner2.setText("");
cp.add(textNenner2);
multiplizieren.setBounds(24, 152, 97, 25);
multiplizieren.setLabel("multiplizieren");
multiplizieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
multiplizieren_ActionPerformed(evt);
}
});
cp.add(multiplizieren);
addieren.setBounds(24, 192, 97, 25);
addieren.setLabel("addieren");
addieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
addieren_ActionPerformed(evt);
}
});
cp.add(addieren);
subtrahieren.setBounds(144, 152, 89, 25);
subtrahieren.setLabel("subtrahieren");
subtrahieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
subtrahieren_ActionPerformed(evt);
}
});
cp.add(subtrahieren);
dividieren.setBounds(144, 192, 89, 25);
dividieren.setLabel("dividieren");
dividieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
dividieren_ActionPerformed(evt);
}
});
cp.add(dividieren);
Bruch1.setBounds(40, 24, 44, 16);
Bruch1.setText("Bruch 1");
Bruch1.setFont(new Font("MS Sans Serif", Font.PLAIN, 13));
cp.add(Bruch1);
labelBruch2.setBounds(96, 24, 52, 16);
labelBruch2.setText("Bruch 2");
labelBruch2.setFont(new Font("MS Sans Serif", Font.PLAIN, 13));
cp.add(labelBruch2);
textErg1.setBounds(200, 48, 25, 24);
textErg1.setText("");
cp.add(textErg1);
textErg2.setBounds(200, 80, 25, 24);
textErg2.setText("");
cp.add(textErg2);
labelErgebnis.setBounds(184, 24, 54, 16);
labelErgebnis.setText("Ergebnis");
labelErgebnis.setFont(new Font("MS Sans Serif", Font.PLAIN, 13));
cp.add(labelErgebnis);
// Ende Komponenten
setResizable(false);
setVisible(true);
}
// Anfang Methoden
public void multiplizieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Multiplikation(B1,B2);
BErg=new Bruch();
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
public void addieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Addition(B1,B2);
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
public void subtrahieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Subtraktion(B1,B2);
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
public void dividieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Division(B1,B2);
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
// Ende Methoden
public static void main(String[] args) {
new GUIBurchrechner("GUIBurchrechner");
}
}
[/Java]
Ich erhalte folgende Fehlermeldung:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at GUIBurchrechner.addieren_ActionPerformed(GUIBurchrechner.java:127)
at GUIBurchrechner$3.actionPerformed(GUIBurchrechner.java:72)
at java.awt.Button.processActionEvent(Button.java:392)
at java.awt.Button.processEvent(Button.java:360)
at java.awt.Component.dispatchEventImpl(Component.java:4630)
at java.awt.Component.dispatchEvent(Component.java:4460)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
:shock:
Was will mir diese Fehlermeldung sagen?
Mein Quellcode:
[Java]currentPost.edit()
import java.awt.*;
import java.awt.event.*;
/**
*
* Beschreibung
*
* @version 1.0 vom 16.10.2009
* @author
*/
public class GUIBurchrechner extends Frame {
// Anfang Attribute
private TextField textZaehler1 = new TextField();
private TextField textField1 = new TextField();
private TextField textZaehler2 = new TextField();
private TextField textNenner2 = new TextField();
private Button multiplizieren = new Button();
private Button addieren = new Button();
private Button subtrahieren = new Button();
private Button dividieren = new Button();
private Label Bruch1 = new Label();
private Label labelBruch2 = new Label();
private TextField textErg1 = new TextField();
private TextField textErg2 = new TextField();
private Label labelErgebnis = new Label();
private Bruchrechner Rechner = new Bruchrechner();
private Bruch B1, B2, BErg;
// Ende Attribute
public GUIBurchrechner(String title) {
// Frame-Initialisierung
super(title);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent evt) { System.exit(0); }
});
int frameWidth = 284;
int frameHeight = 276;
setSize(frameWidth, frameHeight);
Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
int x = (d.width - getSize().width) / 2;
int y = (d.height - getSize().height) / 2;
setLocation(x, y);
Panel cp = new Panel(null);
add(cp);
// Anfang Komponenten
textZaehler1.setBounds(48, 48, 25, 24);
textZaehler1.setText("");
cp.add(textZaehler1);
textField1.setBounds(48, 80, 25, 24);
textField1.setText("");
cp.add(textField1);
textZaehler2.setBounds(104, 48, 25, 24);
textZaehler2.setText("");
cp.add(textZaehler2);
textNenner2.setBounds(104, 80, 25, 24);
textNenner2.setText("");
cp.add(textNenner2);
multiplizieren.setBounds(24, 152, 97, 25);
multiplizieren.setLabel("multiplizieren");
multiplizieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
multiplizieren_ActionPerformed(evt);
}
});
cp.add(multiplizieren);
addieren.setBounds(24, 192, 97, 25);
addieren.setLabel("addieren");
addieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
addieren_ActionPerformed(evt);
}
});
cp.add(addieren);
subtrahieren.setBounds(144, 152, 89, 25);
subtrahieren.setLabel("subtrahieren");
subtrahieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
subtrahieren_ActionPerformed(evt);
}
});
cp.add(subtrahieren);
dividieren.setBounds(144, 192, 89, 25);
dividieren.setLabel("dividieren");
dividieren.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent evt) {
dividieren_ActionPerformed(evt);
}
});
cp.add(dividieren);
Bruch1.setBounds(40, 24, 44, 16);
Bruch1.setText("Bruch 1");
Bruch1.setFont(new Font("MS Sans Serif", Font.PLAIN, 13));
cp.add(Bruch1);
labelBruch2.setBounds(96, 24, 52, 16);
labelBruch2.setText("Bruch 2");
labelBruch2.setFont(new Font("MS Sans Serif", Font.PLAIN, 13));
cp.add(labelBruch2);
textErg1.setBounds(200, 48, 25, 24);
textErg1.setText("");
cp.add(textErg1);
textErg2.setBounds(200, 80, 25, 24);
textErg2.setText("");
cp.add(textErg2);
labelErgebnis.setBounds(184, 24, 54, 16);
labelErgebnis.setText("Ergebnis");
labelErgebnis.setFont(new Font("MS Sans Serif", Font.PLAIN, 13));
cp.add(labelErgebnis);
// Ende Komponenten
setResizable(false);
setVisible(true);
}
// Anfang Methoden
public void multiplizieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Multiplikation(B1,B2);
BErg=new Bruch();
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
public void addieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Addition(B1,B2);
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
public void subtrahieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Subtraktion(B1,B2);
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
public void dividieren_ActionPerformed(ActionEvent evt) {
B1.setBruch(textZaehler1.getText(),textField1.getText());
B2.setBruch(textZaehler2.getText(),textNenner2.getText());
Rechner.Division(B1,B2);
BErg=Rechner.getBruch();
textErg1.setText(""+BErg.Z);
textErg2.setText(""+BErg.N);
}
// Ende Methoden
public static void main(String[] args) {
new GUIBurchrechner("GUIBurchrechner");
}
}
[/Java]
Ich erhalte folgende Fehlermeldung:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at GUIBurchrechner.addieren_ActionPerformed(GUIBurchrechner.java:127)
at GUIBurchrechner$3.actionPerformed(GUIBurchrechner.java:72)
at java.awt.Button.processActionEvent(Button.java:392)
at java.awt.Button.processEvent(Button.java:360)
at java.awt.Component.dispatchEventImpl(Component.java:4630)
at java.awt.Component.dispatchEvent(Component.java:4460)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
:shock:
Was will mir diese Fehlermeldung sagen?
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