JUnit testing custom exception

Question

I'm using JUnit and not quite sure how to test custom exception class. I have created,

public class CustomException extends Exception {

    //@param message is the exception message

    public CustomException(final String message) {
        super(message);
    }

    //@param message is the exception message
    //@param cause is the cause of the original exception

    public CustomException(final String message, final Throwable cause) {
        super(message, cause);
    }
}

main class would have many try catch such as:

catch (ParseException e) {

    throw new CustomException("Date format incorerect", e);

and I'm not sure how to write the test class for it.

To know how to test something you need a specification of what that thing *ought* to do. You have not provided such a specification, so this question is impossible to answer. — Raedwald, Dec 18 '15 at 19:52

score 16 · Accepted Answer · answered Oct 23 '13 at 05:32

16

This page should tell you everything you need to know. For the simplest case, which seems to be your case, just do this:

@Test(expected= CustomException.class) 
public void myTest() { 
  MyObject obj = new MyObject();
  obj.doSomethingThatMightThrowCustomException(); 
}

answered Oct 23 '13 at 05:32

Vidya

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I try your suggestion but Intellij says that CustomException must be caught or declared to be thrown. – Pablo Aleman Mar 22 '19 at 17:27

score 0 · Answer 2 · edited May 31 '16 at 12:22

0

I hope this can help you.

public class YourTestClass
{
    @Test
    public void yourTestMethodName() throws CustomeException {
        //your logic goes here.
        if (condition) {
           throw new CustomeException(<Message to display while throwing an error>);
        }
    }
}

Also you can try the following site http://junit.sourceforge.net/javadoc/org/junit/Test.html

edited May 31 '16 at 12:22

Morgoth

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answered Oct 23 '13 at 05:27

Ashok kumar

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13

JUnit testing custom exception

2 Answers2