Exceptions

BoxLang, like Java, has an exception hierarchy, in addition to the ability to declare custom runtime exceptions. The following are common exceptions thrown by the BoxLang Runtime.

ScopeNotFoundException

This exception is thrown when a scope is requested that does not exist in the current runtime build

This exception might be encountered, for example, in a non-web runtime when attempting to access web-specific scopes like URL or FORM

MissingIncludeException

This exception is thrown when a an included template file cannot be located.

DatabaseException

This exception is the base exception for all database-related errors in the BoxLang runtime.

ConfigurationException

This exception is thrown when an error is encountered during the configuration of the BoxLang runtime or its modules

NoFieldException

This exception is thrown when a field is requested on a Java class that does not exist.

ClassNotFoundBoxLangException

This exception is thrown when a class cannot be found in the BoxLang runtime.

It is most often encountered when attempting to use a struct that has not been declared or is not avaialable in the current scope

LockException

This exception is thrown when a locking operation fails - either with a failure to obtain the lock or due to a timeout

NoConstructorException

This exception is thrown when no constructor is found on a Dynamic Object

It is most often encountered when attempting to construct a Java class with arguments that do not match any of the constructors

ParseException

This exception is encountered when parsing of a source file fails.

CustomException

This is the base exception class for all custom exceptions thrown by the user.

All dynamically declared exceptions will extend this class

ExpressionException

This is the base exception for all expression or evaluation errors in the BoxLang runtime.

BoxRuntimeException

This is the base exception thrown by the BoxLang runtime.

It is a runtime exception, so it does not need to be declared in the method signature of classes or methods which throw it

KeyNotFoundException

The exception thrown when a key cannot be located within a struct

BoxIOException

This exception is thrown when an IO operation fails.

The underlying Java IOException exception is parsed and is used to provide a more user-friendly message.

NoMethodException

This exception is thrown when attempting to access a method on a java class that does not exist, is not accessible or does not match the arguments

BoxCastException

This exception is thrown when an attempt to cast a value to a specific Java type fails.

Most often it is seen when strongly typed arguments or attributes are used in a way that is not compatible with the expected type.

AbstractClassException

This exception is thrown when an abstract class is instantiated.

NoElementException

This exception is thrown when a variable is accessed that does not exist

UnmodifiableException

This exception is thrown when a modification attempt is made upon an unmodifiable (e.g.

final) object

BoxValidationException

This is exception is thrown when an attempt to validate inbound attributes or arguments fails.

Validation upon these attributes or arguments is declared within the respective component or BIF.