why spring handles only unchecked exceptions

I want to know why spring handles only unchecked exceptions..... can any one explain what is the reason behind this .

Spring is using any design patterns which will avoid checked exceptions ?

回答1:

Spring is using any design patterns which will avoid checked exceptions ?

Not a design pattern but Best Practices for Exception Handling.

Consider below code:

public void consumeAndForgetAllExceptions(){
    try {
        ...some code that throws exceptions
    } catch (Exception ex){
        ex.printStacktrace();
    }
}

What is wrong with the code above?

Once an exception is thrown, normal program execution is suspended and control is transferred to the catch block. The catch block catches the exception and just suppresses it. Execution of the program continues after the catch block, as if nothing had happened.

How about the following?

public void someMethod() throws Exception{
}

This method is a blank one; it does not have any code in it. How can a blank method throw exceptions? Java does not stop you from doing this.

I want to know why spring handles only unchecked exceptions?

Personally I prefer unchecked exceptions declared in the throws cause. I hate having to catch exceptions when I'm not interested in them. I agree the spec needs to a few more exception types, but I disagree that they should be checked. Most frameworks rely on unchecked exceptions, not only Spring framework.

Best Practices for Designing the API

If the client can take some alternate action to recover from the exception, make it a checked exception.
If the client cannot do anything useful, then make the exception unchecked. By useful, I mean taking steps to recover from the exception and not just logging the exception.

The Java API has many unchecked exceptions, such as NullPointerException, IllegalArgumentException, and IllegalStateException. I prefer working with standard exceptions provided in Java rather than creating my own. They make my code easy to understand and avoid increasing the memory footprint of code.

See Also:

Unchecked Exceptions
Best practices in exception handling

回答2:

Spring's central theme is Dependency Injection and IOC. Checked exceptions add unncessary code and create more dependency. As such, the dependency costs of checked exceptions outweigh their benefits. They reduce the ability to test code. They lead to lower cohesion and higher coupling. The goal of your code should be high cohesion and low coupling. Spring is focused towards the S.O.L.I.D principles of design.