How the reduce will be complexity of source code and how can reduce the testing cos and with new way?

i didn't understand your answer could you please be more spacific

My first qestion is how to reduce  complexity  of source code such as predefinded function, packages and librar function .its is some much time taken work for develop own source code according to project. now i am talking about  existing of netbeans and eclipse because this tools have more functioins  some time user confused.

2nd thing is testing now day most of company investing more money on mataince and testing of the project because main thing they are not following requrement phase in proper way. sometine client  is also confuse to provide proper way requrement because he doest not have more and specific technical knowledge. regarding this existing some paradigm or model  should  be desing by researcher then this issse will be resolved.