There are a few reasons why a try-catch block might not be working as expected in Java:
The exception is not being thrown: Make sure that the code in the try block actually throws the exception that you are trying to catch. You can use the throws keyword in the method signature to indicate which exceptions might be thrown by the method.
The exception is being thrown, but the appropriate catch block is not being executed: Make sure that the catch block is catching the correct type of exception, and that it is placed after the try block. You can also add multiple catch blocks to catch different types of exceptions.
The finally block is hiding the exception: If the finally block contains code that masks the exception, the exception may not be properly handled. Make sure that the code in the finally block does not interfere with the exception handling.
The exception is not being logged: If you are not seeing any output or error messages, it may be because the exception is not being logged. Make sure to log the exception using e.printStackTrace() or similar, so that you can see what is happening.