Netease
one side
1. Item
2. learn java a few years, and usually learn how to learn java, ah, which read the book?
3.http status code 3xx 4xx 5xx are what
A:
redirection, client error, server-side error
2XX class status code information, said: server successfully receives a client request
3XX class status code information, said: The client browser must to take more action to fulfill the request. For example, the browser may have to request a different page on the server or repeat the request via a proxy server
4XX class status code information, said: error occurs, the client seems to have problems. For example: a client requests a page that does not exist, the client may not provide valid authentication information
5XX class status code information, said: server encountered an error and could not complete the request
Two faces
1.hashmap principles (see source)
2. Which way to achieve thread safety
synchronized, reentrantlock, volatile and focus on that under volatile and in some cases can achieve thread-safe, then put the interviewer to focus on volatile cited as volatile this specialized looked, and sure enough, the interviewer immediately asked volatile.
3, volatile achieve what functions?
Then put yourself too Luanche a pass like that volatile compilation will be modified in the field before adding LOCK field ah, Sha Sha Sha's memory barrier pulled a pass, is to let the interviewer feel that certain aspects still pretty deep understanding of.
4, if you want to implement a thread-safe queue, how you can achieve?
There ArrayBlockingQueue LinkedBlockingQueue Han JUC bag and combine source that a pass.
5, to talk about what http packet header inside?
GET http://download.google.com/somedata.exe
Host: download.google.com
Accept:/
Pragma: no-cache
Cache-Control: no-cache
Referer: http://download.google.com/
User-Agent:Mozilla/4.04en
The example of the first row represents the HTTP client (browser might be, download the program) to get files in the specified URL by the GET method
Host header field
Host header field specifies the requested resource Intenet host and port number
Range header field
Range header field may request a plurality of sub-ranges or entities. For example,
represents the first 500 bytes: bytes = 0-499
represents the second 500 bytes: bytes = 500-999
indicates that the last 500 bytes: bytes = -500
represents the range of the subsequent 500 bytes: bytes = 500-
The first and last bytes: bytes = 0-0, -1
specify several ranges: bytes = 500-600,601-999
6, gave the order in question when a class is loaded, to the sections of the code, allowing you to write the output, load order on ah class constructor of the static code segment.
7, JVM memory partition
8, transaction management database level, what level of default, which would be a problem
9, let the write SQL statements.
- Fast row, dictated to achieve fast-row, time complexity, will not degenerate, then asked fast row optimization, how to pick the benchmark, I said random, and to prevent degradation
Title number on the number of years taken 11.n is s and the two prove safety offer