numberformatexception

Hey Im taking coding lessons at school but the teacher does not explain that well so we have to look for info online which I did, but I was not able to find the error in my code, can you help me please? char end='s'; do{ System.out.println("Tipo de boleto"); char boleto = (char) System.in.read(); switch (boleto){ case 'a': System.out.println("El boleto cuesta $120.00"); System.out.println("Otro boleto (s/n)?"); end = (char) Integer.parseInt(entrada.readLine()); continue; case 'n': System.out.println("El boleto cuesta $75.00"); System.out.println("Otro boleto (s/n)?"); end = (char) Integer

I've uploaded my Android app to the Market today, and I received 4 errors regarding NumberFormatException,Double.parseDouble and Double.valueOf . Here's the Logcat I see in the Developer Console: java.lang.RuntimeException: Unable to start activity ComponentInfo{can.you.drive/can.you.drive.do_drive}: java.lang.NumberFormatException at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1816) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1837) at android.app.ActivityThread.access$1500(ActivityThread.java:132) at android.app.ActivityThread$H

Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: "Total: 8.78" at sun.misc.FloatingDecimal.readJavaFormatString(Unknown Source) at java.lang.Double.parseDouble(Unknown Source) at PizzaOrder$BtnClicked.<init>(PizzaOrder.java:298) at PizzaOrder$BtnClicked.<init>(PizzaOrder.java:295) at PizzaOrder.addListeners(PizzaOrder.java:102) at PizzaOrder.<init>(PizzaOrder.java:76) at PizzaDriver$1.run(PizzaDriver.java:46) at java.awt.event.InvocationEvent.dispatch(Unknown Source) at java.awt.EventQueue.dispatchEventImpl(Unknown Source) at java.awt.EventQueue.access

I get the following exception java.lang.NumberFormatException: Invalid int: "" It is happening when you try to store a value into shared preferences whilst nothing has been inserted into the input field. This is because i am parsing the input as an int (as i need to do a subtraction with the figure) This isn't much of a problem as the app will work however just incase someone using the app wants to be wierd and try and press the save button without entering any data I dont want it to insert. I have tried the following: else if (obj ==null || obj.currentWeight.contains("")||obj.targetWeight

I'm trying to create a for -loop to add views to a layout. The for -loop is working fine (I tried it with initialized variables) but I need to get an integer from an EditText . I used a try-catch and LogCat tells me the following... java.lang.NumberFormatException: invalid int "". The website developers.android.com says this is from incorrectly converting a string to an integer, but I don't understand how I could be incorrectly getting the data from the EditText . This is my code... public class UserPref2Activity extends Activity { @Override public void onCreate(Bundle savedInstanceState) {

In the following code, Clojure (1.2) is printing the wrong message: (try (let [value "1,a"] (map #(Integer/parseInt %) (.split value ","))) (catch NumberFormatException _ (println "illegal argument"))) This should print "illegal argument", but instead it prints a (1#<NumberFormatException java.lang.NumberFormatException: For input string: "a"> . What am I doing wrong? Is this because of the lazy sequence returned by map ? How should it be written? The try special form only catches exceptions that are raised during during the dynamic extent of the body code. Here map is returning a lazy

I have run into a very strange problem in my code. I have a simple temperature converter where the user enters the temperature in Celsius and, after pressing "Convert", the temperature in Fahrenheit is shown. If the user does not enter something valid (anything that is not a number or decimal) an error dialog box is shown. Code: btnConvert.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { try { String tempFahr = (String) enterDegreesC.getText(); double tempF = Double.valueOf(tempFahr); double tempFConverted = tempF * 1.8 +32; displayDegreesF.setText