After the class does not automatically generate annotated compilation @Entity solutions like dynamic queries

Question: After br /> create XXEntity class in IDEA and treated @Entity notes, whether build or rebuild project, the target file directory after compiling generated-sources can not be found QXXEntity this dynamic query class.

Solution:
Click Maven Projects IEDA the right side of the window, find the item -> Lifecycle-> compile, automatically generated QXXEntity class after the compilation is successful, it can be found in the generated-sources, but also can directly use this class in other classes a.

Principle is not particularly clear, in theory, rebuild the entire project will be recompiled. This should be based on jar to create a class, there will be special?