(1) initialization and cleaning formally involve two security issues. Many C ProgramErrors occur because the programmer forgets to initialize the variables. Especially when using the program class library, if the user does not know how to initialize the library components (or other things that the user must initialize ). Cleaning is also a special problem. The resources occupied by this element cannot be released, and the result is that the resources are exhausted;
(2) package COM. oa. text. customer; public class leaf {int I = 0; leaf increment () {I ++; return this;} void print () {system. out. println ("I:" + I);} public static void main (string [] ARGs) {leaf x = new leaf (); X. increment (). increment (). increment (). print () ;}} since increment () returns a reference to the current object through the this keyword, it is easy to perform multiple operations on the same object in a statement; this keyword is also useful for passing the current object to other methods ..
