An instance of this class is thrown if when an assertion fails. This happens when assertions are enabled, and the expression following an assert statement does not evaluate to true. If an assertion fails, and the assert statement has a second expression separated from the first by a colon, then the second expression is evaluated and the resulting value is passed to the AssertionError( ) constructor, where it is converted to a string and used as the error message.

Figure 10-6. java.lang.AssertionError

public class AssertionError extends Error {
// Public Constructors
     public AssertionError( );  
     public AssertionError(long detailMessage);  
     public AssertionError(float detailMessage);  
     public AssertionError(double detailMessage);  
     public AssertionError(int detailMessage);  
     public AssertionError(Object detailMessage);  
     public AssertionError(boolean detailMessage);  
     public AssertionError(char detailMessage);  
}