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I'm sorry Barry,I'm to hurry to post a new topic,I have changed my name already.
I Still have a question: If the GUI should not provide the delete button ,why the DBMain interface has a delete function?
----------------------------------- This is the first time I make a "real" project since I begin to learn java.I feel I was restrict by the instruction and can't think freely .I really want to know how you guys look on the instruction.
Two more things: 1.I begin to learn java for just about one year,Maybe some of the questions I ask will be stupid~~~~~ 2.English is not my native language, maybe some of the sentences will be hard to understand. T_T