0627~ holiday knowledge summary

I've been studying these days springcloud Many components of , Remember the function of components ;

1.eureka( Service registration and discovery ): Used to manage between micro Services ip Address list ;

2.ribbon( Load Balancer ): It solves the problem of client clustering between microservices , Hard coding of transmission address ;

                                 shortcoming : It can't solve the tedious redundancy of parameter splicing ;

3.feign( Load Balancer ): The bottom layer has been integrated ribbon And hystrix, It solves the communication problem between microservices , And solved the problem of participation                                    Redundancy of data splicing , tedious ; You can also use hystrix Circuit breaker , Write supporting data ;

4.hystrix( Fuse ): It solves the avalanche problem between microservices , If an error occurs in a microservice , It will lead to the paralysis of the whole micro service ; So there is hystrix after , If an error occurs in a microservice , It will start the bottom data return , No error messages will be thrown ;

5.zuul( gateway ): All login or request between microservices should be verified , There will be a lot of repetitive code and operations , therefore zuul And then it came out , All requests must pass zuul, Resend to client , Just check it once ,zuul The core function is mainly to verify , Fuse , Filter ;

6.config( Configuration center ): Centralized management of all configuration files ; In this way, you don't have to type again every time you modify the configuration file jar It's packed ;

                             Write the configuration file directly in gitee On , Realize online configuration management ; shortcoming : Restart the client after each modification                                 mouth , It will be very trouble , Not elegant ;

7.bus( The message bus ): Elegantly solved config The shortcomings of ; Online configuration management can be realized , And do not restart the port ;

I also read many interview questions today ;

1.hashmap The underlying principle of ?

2.hashmap Are threads safe ?

3. You are right about spring The understanding of the ?

4.springboot What is the starting principle of ?

5. What are the ways to create multithreads ?

6. When will multithreading be used ?

7. What are the advantages of microservices ?