Generate and Use Java Components › The Basics of Java Application Programming › Data Conversions and Exception Handling

Data Conversions and Exception Handling

The Java Interface Layer supports the following conversion from Aion BRE data types to Java data types.

* Name of the exported class.

Exceptions are thrown by the Aion program during data conversion for Unknown and Null values, or when a constant violation occurs. These exceptions are subclasses of AionException, which is provided in the ca.aion.j2aion package.

• When an Aion attribute is unknown, an AttributeUnknownException is thrown.
• When an Aion attribute is Null, an AttributeNullException is thrown.
• When an assignment violates a constraint, an AttributeConstaintException is thrown.

You can catch these exceptions in the Java programming with standard exception handling:

try{

myObject.getAttribute();
} catch (AttributeUnknownException aue) {
// the Attribute is unknown in Aion.
}