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Meituan social recruitment Java advanced development side, two sides, three sides, four sides of the merger, has been offered

Meituan comments on social recruitment java one side

1、 Introduce yourself , Just say a little bit about your project ?
2、 Have you ever encountered a memory leak ? How did you solve it ? I did meet once a while ago , It's a bit of luck .
3、java What are the basic types of ?String Is it right? java Basic type ?String Why if final Type of ?
4、 What is the underlying implementation of the reflection mechanism ? dynamic Well ? dynamic Implementation principle of ?
5、hashmap Understand? ? The way hashmap Something related ?hashmap Is it thread safe ? Why thread safe ?concureenthashmap Understand? ? How does he achieve thread safety ? You just said 1.8 be based on cas?cas Of ABA How to solve the problem ?
6、 The way JVM Thread model of ? What are these areas for ?java Thread model and jvm Pay attention to the distinction of thread model 、 Sum up , Many articles on the Internet are wrong .
7、 The way java How class loaders work ? Class loading in that area ?
8、 The way java Thread model of ?violate Understand? ? What's his principle ?violate Is it thread safe ? Why not ?
9、 What are the solutions to ensure thread safety ? Let's talk about the read-write lock , Read write lock read
10、 What are the indexes of the database ? Why use B+ Trees to index ? What's the difference between a composite index and several individual indexes ? Database large table query optimization understand ?MVCC Mechanism understanding ?MVCC What's wrong with the mechanism ? How to solve this problem ?mysql Have you ever done slow sentence tuning ? Tell me how you did it ?
11、redis Understand? ? Tell me how to use redis Implement distributed locks ?
12、spring in Bean Scope of action ,springMVC Of controller Is it thread safe ? How to ensure thread safety ?
13、 Has message queuing ever been useful ? Tell me how you use it ? It doesn't feel like you're using it like that, right .. Embarrassment in capital ..
14、 Do you understand computer networks ? say TCP Three handshakes and four waves , Feel this really is the computer network must test knowledge point , Every time I ask about the computer network, I ask this .time_wait What is the cause of the State ?, What's the harm ? How can we avoid ?
15、leetcode153. Look for the minimum value in the rotation sort array
Let's say that the array sorted in ascending order is rotated at a point that is not known in advance .

( for example , Array [0,1,2,4,5,6,7] It could be [4,5,6,7,0,1,2] ).

Please find the smallest element .

You can assume that there are no duplicate elements in the array .

Example 1:

Input : [3,4,5,1,2]
Output : 1

Example 2:

Input : [4,5,6,7,0,1,2]
Output : 0

What do you have in your hand offer 了 ? When can I get on the job as soon as possible ? What else do you want to ask ? And then said there would be hr Contact you , The next day I received hr About two days' notice .

Sum up , The interview asked a wide range of things , And the questions are very detailed , A knowledge point is basically asked to answer so far . There are still a lot of things to strengthen ? In meituan's interview, I still learned something .

Meituan commented on two sides

1. First of all, the project . The questions were quite detailed , More complete .
2.String,StringBuffer,StringBuilder The difference between , Why? String It's immutable ,StringBuffer and StringBuilder Which is thread safe , What scenarios do they apply to .
3.java How the class loading process works , The way volatile.
4. Do you understand ? If several threads wait for each other , Which concurrent class can be used to implement , What's his principle ?
5. Database slow query optimization to know what ? Said a lot , The interviewer said that if these have been done or slow to do ? Finally, I asked the following examiners , Interviewers mainly want to know the knowledge of database partition .
6. The way spring The starting process of the container ?
7. Let's talk about distributed locks , be based on zookeeper The implementation and redis What are the differences in performance between implementations ?
8.kafka How to ensure that there is no loss of news and no repeated consumption . Understand some big data related technologies ?
9. Finally, I wrote a question ,leetcode55. Jumping game
Given an array of nonnegative integers , You are first in the array .

Each element in the array represents the maximum length you can jump at that location .

Judge whether you can reach the last position .

Example 1:

Input : [2,3,1,1,4]
Output : true
explain : We can jump first 1 Step , From the position 0 arrive Location 1, And then from the position 1 jump 3 Step to the last position .

Example 2:

Input : [3,2,1,0,4]
Output : false
explain : No matter what , You will always arrive at the index for 3 The location of . But the maximum jump length for this position is 0 , So you can never get to the last place .

When is the quickest time to come ? What questions do you want to ask ? And then there's the back hr I'll get back to you .

Meituan commented on three aspects

The interviewer first asked for some basic information in his resume . Draw a picture of what projects your project interacts with , What's its place in your product

Draw the architecture of your project , Choose a business scenario that you find difficult to talk about ,

What problems have you encountered in this project ? Tell me how you all ended up solving this problem

Wrote a piece of code , Ask the code what the final output is ? How much memory space to apply for , Where did you apply for

public class Test {

public static void main(String[] args) {

String str = "hello";
        test(str);
        System.out.println(str);
    }

public static void test(String str){
        str = str + "world";
        System.out.println(str);
        int[] a = new int[1024];
    }
}

hashmap Understand? ? His set and get What is the time complexity of ? Why O(1), Let's talk about the detailed process ,hashmap Is it thread safe ?
Jvm Understand? ?jvm Which of them can be recycled as garbage gcroot? Why? ?
When can I come to work ? And then he said wait a minute hr Noodles .

Meituan comments on four sides ,hr Noodles

Asked about the basic information , When can I come over , Why do you want to change jobs ? Performance and salary at home , What is the expected salary .

 

版权声明
本文为[Programmer Bai Nannan]所创,转载请带上原文链接,感谢

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