How To Set Error Message In Java
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here for a quick overview of the site Help Center Detailed answers to any questions you might have Meta Discuss the workings and policies of this site About Us Learn more about Stack Overflow the company Business Learn more java change exception message about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users display error message java Badges Ask Question x Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping throw exception with message java each other. Join them; it only takes a minute: Sign up How can I set the message on an Exception in JAVA? up vote 4 down vote favorite I want to set a custom exception message however I'm java throw exception with message example unsure of how to do this. Will I need to create a custom exception class or is there an easier way of doing this? Sorry in advance if this is a simple question, however I've been looking around online and haven't had much luck. java exception share|improve this question asked Jan 17 '12 at 13:05 The Crazy Chimp 3,6691972130 1 Even java.lang.Exception (docs.oracle.com/javase/1.5.0/docs/api/java/lang/Exception.html) has a constructor with a String. –anubhava Jan 17 '12 at 13:10 add
Joptionpane Message
a comment| 7 Answers 7 active oldest votes up vote 6 down vote accepted Well, if the API offers an exception that suits your needs (IllegalArgumentException for example), just use it and pass your message in the constructor. share|improve this answer answered Jan 17 '12 at 13:08 quaylar 1,4951816 add a comment| up vote 18 down vote Most standard exception classes provide a constructor that takes a mesage, for example: public UnsupportedOperationException(String message) { super(message); } The above class simply calls its parent's constructor, which calls its parent's constructor, and so on, ultimately culminating in: public Throwable(String message) { ... } If you create your own exception class, I think it's a good idea to following this convention. share|improve this answer answered Jan 17 '12 at 13:07 NPE 254k36555745 add a comment| up vote 2 down vote The best approach is to wrap the exception. try { my code that throws E; } catch (final E e) { throw new MyE("my message", e); } share|improve this answer answered Jan 17 '12 at 13:09 Sam 2,073810 add a comment| up vote 2 down vote You can only set the message at the creation of the exception. Here is an example if you want to set it after the creation. public class BusinessException extends RuntimeException{ private Collection
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Java Custom Exception Example
site About Us Learn more about Stack Overflow the company Business Learn more java exception message about hiring developers or posting ads with us Stack Overflow Questions Jobs Documentation Tags Users Badges Ask Question x java exception getmessage Dismiss Join the Stack Overflow Community Stack Overflow is a community of 4.7 million programmers, just like you, helping each other. Join them; it only takes a minute: Sign up How to http://stackoverflow.com/questions/8895091/how-can-i-set-the-message-on-an-exception-in-java set my own Message in my custom Exception in java that can be reteived my getMessage() BUT WITHOUT Using the Constructor, is there any way? up vote 2 down vote favorite 1 I'm just Learning Exception Handling in Java, What i would like to know is rather than trying something like say, throw new Exception("My Message"); and String message=ex.getMessage(); System.out.println(message); Take a look at http://stackoverflow.com/questions/26313084/how-to-set-my-own-message-in-my-custom-exception-in-java-that-can-be-reteived-my the code below , class ExceptionTest { public static void main(String[] args) { ExceptionTest t1=new ExceptionTest(); try { t1.riskyMethod();//call the risky or exception throwing method } catch(MyException myex) { System.out.println("Exception has been thrown"); String message=myex.getMessage();//get the String passed during exception call System.out.println("The message retrived is "+message); myex.printStackTrace();//prints name of exception and traces the function call stack } }//main ends void riskyMethod() throws MyException {//a method that can throw an excpetion int rand=(int)(Math.random()*10);///Math.rand return 0 to .9 range value if(rand>5) { //throw new MyException(); or try this // MyException myexception=new MyException(); // myexception.setMessage("HI THIS IS A SAMPLE MESSAGE"); String mymessage="Sample Exception Message..."; throw new MyException(mymessage); } else System.out.println("No exception"); } }//Exception class ends While this works fine i want to know if i can avoid calling super(message) etc and just set some variable 'message' in my subclass MyException that changes the message retrived on a call to exception.getMessage() In other words what is the name of the String Variable that store the message string passed to the constructor and can i set it manually , is it final or private , if so is there any setter method for it ,
LDAPJPAJSPJSTLLanguage BasicsNetwork ProtocolPDF RTFReflectionRegular ExpressionsScriptingSecurityServletsSpringSwing ComponentsSwing JFCSWT JFace EclipseThreadsTiny ApplicationVelocityWeb Services SOAXMLDisplay error message dialog with JOptionPane.ERROR_MESSAGE http://www.java2s.com/Code/Java/Swing-JFC/DisplayerrormessagedialogwithJOptionPaneERRORMESSAGE.htm : OptionPane«Swing JFC«JavaJavaSwing JFCOptionPaneDisplay error message http://www.homeandlearn.co.uk/java/java_error_handling.html dialog with JOptionPane.ERROR_MESSAGE import javax.swing.JOptionPane; import javax.swing.JPanel; public class JOptionPaneERROR_MESSAGE { public static void main(String[] args) { final JPanel panel = new JPanel(); JOptionPane.showMessageDialog(panel, "Could not error message open file", "Error", JOptionPane.ERROR_MESSAGE); } } Related examples in the same category1.A Program that Uses the JOptionPane Class to Get User Input2.Demonstrates JoptionPane3.OptionPane Sample: simple dialog4.JOptionPane demo5.JOptionPane utilities6.Simple Input Dialog7.Demonstrate JOptionPane8.Display warning throw exception with message dialog with JOptionPane.WARNING_MESSAGE9.Display question message dialog with JOptionPane.QUESTION_MESSAGE10.Display information message dialog with JOptionPane.INFORMATION_MESSAGE11.Show a message dialog with JOptionPane12.Create a message dialog box with different options13.Show message in two lines in a dialog box14.Modal dialog with yes/no button15.Modal dialog with OK/cancel and a text field16.Wait (forever) for a non-null click and then quit17.Create a Confirm Dialog Box18.Create a Message Dialog Box19.Use a JOptionPane20.Yes no cancel dialog21.OK cancel option dialog22.Dialog with default options23.Localize a JOptionPane dialog24.Customize JOptionPane buttons25.Exercise Options26.Modifiable JOptionPane27.Message dialog helper28.Exercise all JOptionPane based dialogsjava2s.com |Email:info at java2s.com|© Demo Source and Support. All rights reserved.
can be broken up into two categories: Design-time errors and Logical errors. Design-time errors are easy to spot because NetBeans usually underlines them. If the error will prevent the program from running, NetBeans will underline it in red. Logical errors are the ones that you make as a programmer. The program will run but, because you did something wrong with the coding, there's a good chance the entire thing will crash. You'll see examples of run-time errors shortly. You'll also see how to handle them. But first a word on how Java handles errors. Exceptions In Java, errors are handled by an Exception object. Exceptions are said to be thrown, and it's your job to catch them. You can do this with a try catch block. The try catch block looks like this: try { } catch ( ExceptionType error_variable ) { } The try part of the try catch block means "try this code". If something goes wrong, Java will jump to the catch block. It checks what you have between the round brackets to see if you have handled the error. If you have the correct Exception type then whatever code you have between the curly brackets of catch will get executed. If you don't have the correct Exception type then Java will use its default exception handler to display an error message. As an example, create a new console application. Call it anything you like. In the code for the Main method, enter the following: try { int x = 10; int y = 0; int z = x / y; System.out.println( z ); } catch ( Exception err ) { System.out.println( err.getMessage( ) ); } In the try part of the try catch block, we have set up three integers, x, y and z. We are trying to divide y into x, and then print out the answer. If anything goes wrong, we have a catch part. In between the round brackets of catch we have this: Exception err The type of Exception you are using comes first. In this case we are using the Exception error object. This is a "catch all" type of Exception, and not very good programming practice. We'll change it to a specific type in a moment. After your Exception type you have a space then a variable name. We've called ours err, but you can it almost anything you like. In the curly brackets of catch we have a print statement. But look what we have between the round brackets of println: err.getMessage( ) getMessage is a method available to Exception objects. As its name suggests, it gets the error message associated with the Exception. R