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1. Execution process chart of struts 2 The whole implementation process is divided into two parts: 1. Server start - > initialization filter - > Load struts.xml 2. Browser send request - > filter - > struts.xml Find action class name in - > instantiate action class The action class w ...

This article is translated from: How to push a docker image to a private repository I have a docker images tagged as me / my image, and I have a private repo on the dockerhub named me private. When I push my me / my image, I end up always hiding the public repo. What is the exact syntax to specifi ...

What is a state management function The state management functions in Spark Streaming, including updateStateByKey and mapWithState, are used to count changes in the state of the global key.They reduce by key with data from DStream, then accumulate data from each batch as new data information enters or updates.To keep users in whatever shape t ...

For the source code of this tutorial, please visit: tutorial_demo 1, What is dynamic agent 1.1 concept The purpose of dynamic proxy is similar to decoration mode, which is to enhance an object. All cases that use decorator mode can be replaced with dynamic proxies. Features: bytecode is created on demand and loaded on demand; Function: enhanc ...

For the source code of this tutorial, please visit: tutorial_demo In the previous tutorial, we used pure annotation and Apache Commons DbUtils to implement CRUD operation of single table, but the operation in this tutorial does not support transaction. In this tutorial, we changed it to transaction support version according to the existing kno ...

1. Introducing dependencies <!-- https://mvnrepository.com/artifact/org.apache.mina/mina-core --> <dependency> <groupId>org.apache.mina</groupId> <artifactId>mina-core</artifactId> <version>2.0.7</version> </dependency>   2. Create ...

After verification, upgrade from 3.0.0 to 3.9.7 in the following way. At the same time, support users to change passwords through the web interface. Every user forgets his password and needs the administrator to change it. The workload is not large, but it's really time-consuming and laborious. It's not flattering!1. Installation software prep ...

A Preliminary Study on the Use and Design of cola Extension Points Packaging changes provide flexibility to respond to changes in program requirements. Extension point use Steps: Defines an extension point interface, which can be a validator, converter, entity; must end with ExtPt to represent an extension point. For example, I define an exten ...

Kafka Stream concepts and initial high-level architecture diagrams Kafka Stream is a new Feature introduced by Apache Kafka from version 0.10 that provides streaming and analysis of data stored in Kafka.In short, Kafka Stream is a class library for stream computing, similar to Storm, Spark Streaming, Flink, but much lighter. Basic concepts of ...

Conversion operation of DStream The DStream API provides the following methods related to transformation operations: Examples of transform(func) and updateStateByKey(func) methods are given below: (1), transform(func) method transform methods and similar transformWith(func) methods allow any RDD-to-RDD function to be applied on DStream and can ...