Datang Telecom Java Pen Test (do not know which year drop)

1. Describe the use of the Public,protected,private,final keyword in Java

Scope Current class same package descendant class other package

Public√√√√

Protected√√√x

Friendly√√xx

Private√xxx

Public, protected, and private are all to modify the scope of variables and methods, and final is to modify the variables and methods are immutable variables or not inheritable methods (generally for some fixed modules in the project use) 2. What is the difference between Abstract class and interface?

There are a lot of differences between Abstract class and interface, see http://blog.csdn.net/yu422560654

3. What is the difference between Vector and ArrayList? What's the difference between HashTable and HashMap?

4. What does the iterator in the Java collection work

5. What are the different ways to create an object in Java?

6. There are several ways to express multithreading, what is it? There are several ways to achieve synchronization.

7. Describe the exception mechanism in Java, what is

8. Describe the working principle of Java ClassLoader or EE ClassLoader? (You can paint

9. What technologies do all parts of MVC have to implement?

10. Describe the way struts works

How many built-in objects are included in the JSP?

What are the two ways of jumping in JSP? What's the difference?

13. Describe the usage of taglib in JSP

How to verify a digital type in JavaScript

What is included in EJB2.0? What is the effect of the difference

16. What components does a sessionbean contain? What are the functions of each component?

17. Describe the EJB deployment file in an EJB application, and the role of the deployment file for your familiar app server

18. List the design patterns (including EJB,J2EE design patterns) that you know and the situations they apply

19. What are the main methods of parsing XML? What's the difference?

20. Do you know the project of open source? If you understand please describe a few, and tell about their role

21. What kind of Java books have you read, can you list them?