Java pen questions

1. What is J2EE?

2. Introduction to the Collection framework in Java (including how to write your own data structure )?

For example, what is the difference between the legacy classes (hashtable and vector) in collection and the existing classes? (Synchronous)

3. What is the exception handling mechanism and event mechanism in Java?

4. What is the difference between EJB and Java Bean?

EJB And Java Bean Yes Sun Different Component specifications, EJB Is running in the container, in a step-by-step manner, and Java Bean It is mainly an available component, mainly on the client UI Performance.

5. JavaIn the multi-form and inheritance?

 

Programming and multiple-choice questions are available.

6. abstract classes and interfaces?

The advantage of the interface is that the implementation and performance are separated.

Abstract classes and interfaces are used for abstraction, but abstract classes (in Java) can have their own partial implementations, while interfaces are completely an identifier (with multiple inheritance functions at the same time ).

7. Java communication programming, programming questions (or Q & A), using Java socket programming, read the server several characters, and then write the local display?

8. What is the difference between forward () and redirect () in Java Servlet APIs?

The forward () method can use the original object, and the speed is faster.

9. How does Java Parse XML?

Sax, Dom

10. Use Java to implement database query. This is a programming question.

Basic operations.

11. How can I implement sorting and comparison in Java )?

For example, in the collection framework, what interfaces should be implemented.

12. What is the difference between dynamic include and static include in JSP?

The old one can include parameters dynamically, which is equivalent to a static html file.

13. What is the difference between an application server and a web server?

14. Design Patterns and UML.

For example, the factory mode solves the problem of multi-database support.

15. Programming: compile a function to intercept a string. The input is a string and the number of characters, and the output is a byte string.

However, make sure that no half of Chinese characters are cut, such " Me ABC "4 , Should be intercepted " Me AB" , Input " Me ABC Han Def" , 6 , The output is " Me ABC" Instead " Me ABC + Half a Chinese " .

16. Solution for paging in the case of large data volumes in Oracle. The ID truncation method is generally used, and the layer-3 nested method is also used.

17. Web Service glossary. Jswdl Development Kit introduction. JAXP and jaxm. Soap and UDDI interpretation.

18. The connection and difference between Bs and CS.

19. Linux thread, the explanation of the GDI class.

20. Java multi-thread programming.

Write a multi-thread program in JavaProgramFor example, write four threads, add two to one, and subtract one from one variable to output.

21. Java basic skills: the difference between string and stringbuffer.

22 . Struts Application ( For example Struts Architecture )