(In struts 2-core-2.1.8.1. jar/ora. apache. struts 2/default You can see many Struts 2 constants in properties. Changing some constants during development is helpful. Sometimes the program also needs to change the constants inside: so it is very important to understand the meaning of these constants (but if you are good at English, just look at the attribute file directly)
Configure. txt in struts 2-2.1.8.1 constant)