No. 1 store Java Engineer

On Tuesday, no. 1 store's Java engineer crashed. In order to commemorate the loss of leave + the toll of several hundred yuan, or write a face Sutra ~~

 

The interview location is still in Zhangjiang, a very imposing building (I forgot how many floors ~). Enter the information table first, which is very standard. The interviewer will be there. The interviewer looks rough, but it's just a pair of eyelids. I took the room to close the room on the fourth floor and took out two pen-related questions, so that I could finish the work in half an hour.

 

I went there and saw the same content on the Internet. (even though I can't find the webpage after I came back, the content I recalled was not written at the end of this Article ), it seems that the No. 1 store is fixed with a set of (at most a few) pen questions. It is certainly not difficult for programmers who have worked in e-commerce or course-class training. However, as I leave my home, I have a lot of basic knowledge. I can only do it based on my feelings and my impressions on the Internet, it's estimated that it's about half of the idea. At that time, it was just a hunch ~

 

Half an hour later, the interviewer came in and did not take the exam too carefully (it is estimated that it is not reliable at a glance ...). In fact, the written test is just a guide. Even if you know the standard answer, you will not be able to understand it. Let's talk about the project first. If we talk about it, he doesn't feel anything at all. It may be that our wild path Intranet project doesn't come into his eyes. Speaking of how we use socket to transmit files, he indicates that he has never heard of it... in short, his overall attitude is "How do you think of such a project ?"~~~

 

Then I asked how to ensure that the persistent connection status is normal (the answer is heartbeat )? How can I ensure that the command arrives correctly and is executed (the answer is to reply back to the package )? If the command is correctly executed but the response is not sent back, how can this problem be solved (the answer is rollback )? When the answer is not so accurate, but it is still a good deal. I feel that the interviewer's questions all have a keyword. You must make it clear. For example, what should he do if the connection is disconnected? I say "reconnection". He looks at me with disdain, which makes people feel wrong. Then he said that reconnect is performed every few seconds, and there is a policy at the interval. I said that reconnect in my project is implemented with a policy, he said, "Why didn't you say that?" orz... I thought he knew how to reconnect ......

 

Then, we will go to the database-related questions that are miserable. I really don't know how to deal with concurrent queries. I can only say "use locks" in general, and I am despised... ask what is left join, don't know, be despised... we have to say that our project mainly deals with communication and logic, and the databases used are basically single tables, which are seriously despised, the interviewer reluctantly said, "What do you want me to ask you?" So far, it is almost gone.

 

Then he began to ask me a question, that is, leave without a problem. I asked if the three frameworks are critical? He said that a lot of applications are used, but the framework is not important and will soon be able to learn. The main reason is that I have a poor foundation in the database (it is also a fact and should be supplemented ).

 

The interview ended like this and did not go into either of them. Fortunately, Baidu is still playing. I feel that e-commerce is still more orthodox in terms of technical requirements (at least basic technology). People who are familiar with it should be easier to get familiar with it, and those who are not familiar with it will be difficult to get involved ~~

 

Appendix: Questions (80% complete)

1. What are the steps for accessing the database? What is the difference between statement and preparedstatement?

2. What is threadlocal? What is the purpose?

3. What is the difference between session and cookie? How can we use the two methods to share user information between servers?

4. Three tables: User, role, and permission. One user has multiple roles and one role has multiple permissions.

1) write the table creation statement

2) query all permissions of user John

3) query all users with permissions greater than 3

5. select one of the following three items:

1) value transfer mechanism of struts2

2) What is spring? (forgot)

3) common design patterns of spring