org.junit.rules
Class ExpectedException

java.lang.Object
  extended by org.junit.rules.ExpectedException
All Implemented Interfaces:
MethodRule

public class ExpectedException
extends Object
implements MethodRule

The ExpectedException Rule allows in-test specification of expected exception types and messages:

 // These tests all pass.
 public static class HasExpectedException {
        @Rule
        public ExpectedException thrown= new ExpectedException();
 
        @Test
        public void throwsNothing() {
    // no exception expected, none thrown: passes.
        }
 
        @Test
        public void throwsNullPointerException() {
                thrown.expect(NullPointerException.class);
                throw new NullPointerException();
        }
 
        @Test
        public void throwsNullPointerExceptionWithMessage() {
                thrown.expect(NullPointerException.class);
                thrown.expectMessage("happened?");
                thrown.expectMessage(startsWith("What"));
                throw new NullPointerException("What happened?");
        }
 }
 


Method Summary
 Statement apply(Statement base, FrameworkMethod method, Object target)
          Modifies the method-running Statement to implement an additional test-running rule.
 void expect(Class<? extends Throwable> type)
          Adds to the list of requirements for any thrown exception that it should be an instance of type
 void expect(Matcher<?> matcher)
          Adds matcher to the list of requirements for any thrown exception.
 void expectMessage(Matcher<String> matcher)
          Adds matcher to the list of requirements for the message returned from any thrown exception.
 void expectMessage(String substring)
          Adds to the list of requirements for any thrown exception that it should contain string substring
static ExpectedException none()
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Method Detail

none

public static ExpectedException none()
Returns:
a Rule that expects no exception to be thrown (identical to behavior without this Rule)

apply

public Statement apply(Statement base,
                       FrameworkMethod method,
                       Object target)
Description copied from interface: MethodRule
Modifies the method-running Statement to implement an additional test-running rule.

Specified by:
apply in interface MethodRule
Parameters:
base - The Statement to be modified
method - The method to be run
target - The object on with the method will be run.
Returns:
a new statement, which may be the same as base, a wrapper around base, or a completely new Statement.

expect

public void expect(Matcher<?> matcher)
Adds matcher to the list of requirements for any thrown exception.


expect

public void expect(Class<? extends Throwable> type)
Adds to the list of requirements for any thrown exception that it should be an instance of type


expectMessage

public void expectMessage(String substring)
Adds to the list of requirements for any thrown exception that it should contain string substring


expectMessage

public void expectMessage(Matcher<String> matcher)
Adds matcher to the list of requirements for the message returned from any thrown exception.