Use unit testing and Jmock to aid in testing individual parts of code.

1. +
Using JMock
By Jeff Dilley

2. +
Unit Testing
 What’s a ‘unit’?
 Code Isolation is important
 Code needs to be ‘testable’

3. +
jMock
 Used with jUnit
 Handles classes that rely on dependency injection / IOC
 Helps further isolate testing

4. +
jMock
 Expectations
 One(userService).getUser(someUserId);
will(returnValue(any(User.class))));

5. +
jMock
mockCtx.checking(new Expectations() {{
one(jSONServiceHelper).checkSession(request); will(returnValue(true));
exactly(2).of(request).getSession(); will(returnValue(session));
one(jSONServiceHelper).retriveCartVOFromSession(session); will(returnValue(cartVO));
one(jSONCartProcessingService).getProductDetails(price, prodId, duns); will(returnValue(tempCartVO));
one(jSONCartProcessingService).processShoppingCart(cartVO); will(returnValue(cartVO));
atLeast(1).of(session).setAttribute(WebCartConstants.WEBSALES_SESSION_CART, cartVO);
}});