Jython Essentials

Appendix C. Jython Exceptions

The following is a list of Python language exceptions raised by Jython, along with a discussion of their potential Java equivalents. Deprecated exceptions are not included.

ArithmeticError

Abstract base class of all the mathematical exceptions (such as ZeroDivisionError).

AssertionError

Raised by Python’s assert statement, which has the form assert expression, message. If the expression evaluates to false, the exception is raised, with the optional message as additional data. In Java 1.4, an assert statement and an AssertionError have been added to the language.

AttributeError

Raised when an attempt to reference or call an object attribute fails because the object does not have the attribute. The attribute name is the value of the exception. Java generally catches these in compilation, but if you are using reflection, it can either be a NoSuchFieldException or a NoSuchMethodException. If you try to call an attribute of a None value, you’ll get this exception as well, so NullPointerException is also related.

EnvironmentError

Abstract base class for exceptions raised outside Jython (such as OSError and IOError). Usually created with two arguments. The first is placed in an attribute called errno, and the second is in the attribute strerror and is usually the external error message. There is an optional third attribute, filename.

EOFError

Raised when a built-in read function hits the end of a file and hasn’t read any data. Similar to java.io.EOFException.

Exception ...