The Business Components for Java framework follows the Java platform model for conveying information about run-time errors, so a method can return a result code (also called an error code), throw an exception, or both. Following are some recommendations.
Use exceptions for serious or unexpected error conditions, use result codes for simple warnings. In general, exceptions are more expensive than result codes: they use more system resources and take longer to process.
Use an 80/20 rule. If the calling routine is likely to be aware of the condition (for example, end-of-list) roughly 80 percent of the time, return a result code. If callers are likely to be aware 20 percent of the time, throw an exception.
If stack unwinding will be a serious chore, throw an exception.
The following topics describe how to write error-handling routines: