How to write partially in file.

Can anybody please tell me how to write partially in file.

What I want to know is , is there any method in writer classes of java.io package using which i can write partially in file.Or else I have to do it by myself.

Situation is , I have a file which holds some records , I save records in file using writeln() function of Printwriter class. Now if i want to delete any records or edit I have to read the whole file , delete or change the respective record and then write the whole file again in write mode by opening new file with same name.

I dont want to write the complete file, I want only to edit the records not the whole file writing?

Please Help...