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Install K8S on VM and spring boot integration.

Installation Environment Vmware Workstation pro  It is recommended to use the  snapshot  to store the state of each installation stage to avoid installation failures and causing the installation to start from scratch. Ubuntu 22.04 windows 11 Hardware settings  create 3 VM: 4 cores and 4G memory and 100G capacity Before installing K8s (All use the root user) set host: 192.168.47.135 master 192.168.47.131 node1 192.168.47.132 node2 set root ssh connection: sudo su - echo "PermitRootLogin yes" >> /etc/ssh/sshd_config systemctl restart sshd sudo passwd ssh-keygen for i in {master,node1,node2}; do  ssh-copy-id root@$i; done set Ipvs and conf  create conf file: for i in {master,node1,node2}; do ssh root@$i 'cat << EOF > /etc/modules-load.d/containerd.conf overlay br_netfilter EOF'; done execute conf: for i in {master,node1,node2}; do ssh root@$i 'modprobe overlay;modprobe br_netfilter;'; done create 99-kubernetes-cri.conf file: for i in {maste...
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Proxy

Proxy in design pattern

The proxy pattern is a software design pattern, as a wrapper or agent object that is being called by the client to access the real serving object behind the scene.

There are two advantages:

  • Provides access control for real objects.
  • Provides additional functionality when accessing real objects.

And there are two types of proxy:
  • Static proxy: proxies are created manually. Java example on GitHub.
  • Dynamic proxy: proxies are created by JDK Proxy or CGLib Proxy with reflection.

JDK proxy

Before the proxy object is created, it must implement the invoke method of the InvocationHandler, which is invasive to the target object.
JDK Dynamic proxy can only proxy by the interface (so your target class needs to implement an interface, which is then also implemented by the proxy class)

CGLib proxy

The proxy object is created by implementing the intercept method of MethodInterceptor, and the target object does not need to implement this method but implements it through subclasses to reduce code invasion.

It is a byte instrumentation library used in many Java frameworks such as Hibernate or Spring. The bytecode instrumentation allows manipulating or creating classes after the compilation phase of a program.


reference:

https://en.wikipedia.org/wiki/Proxy_pattern

https://stackoverflow.com/questions/10664182/what-is-the-difference-between-jdk-dynamic-proxy-and-cglib

https://www.cnblogs.com/carpenterlee/p/8241042.html

https://www.baeldung.com/cglib

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GC Basic Algorithm

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OS basic

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