Jaybird 2.1 JDBC driver Java Programmer's Manual - Firebird

3. Handling exceptions
Chapter 3.
An exception handling is probably the most important aspect that directly affects
the stability of the application. Correct handling of the error cases guarantees
correct functioning of the client code as well as the database server. Additionally,
all methods of the interfaces defined in the JDBC specification throw instances of
java.sql.SQLException to notify about all error conditions that happen during
request processing. The SQLException is checked exception, which forces Java
programmer to either handle it with the try/catch clause or redeclare it in the
method signature.
Working with exceptions
The exception handling becomes even more important if we consider that this
topic is either ignored or presented in incorrect form in the most JDBC tutorials.
The official JDBC tutorial from Sun Microsystems briefly mentions that
exceptions should be handled by using try/catch blocks only at the end of the
course, but neither reasons of doing this nor the best practices are presented.
There are few reasons to think about exception handling in your applications
before you start coding. First of all, it is very hard to change the exception
handling pattern in the existing code. The changes will affect all layers above the
place where the changes in exception handling are made and the new application
must be thoroughly tested after the change.
Another reason was already mentioned on the beginning of this chapter –
instances of java.sql.SQLException is the only way for the RDBMS server to
notify about the error condition that happened during request processing. By