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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 ...

>Following the previous article "Apache Shiro takes over the authentication and authorization of Swagger", some enthusiastic netizens said that Apache Shiro seems too simple. In response to this problem, the individual does not make any evaluation (all technologies serve the needs). Today's main share is: how to take over the authe ...

Built a set of elk by myself 7.x Version environment found that using filebeat to collect nginx or apapche could not customize the directory log directory. If you customize the log directory, it would not be segmented. If you use the default log location, it would be segmented The solution is hereby recorded Default load path [root@kangcw e ...

Purchase domain name. Example: example.com Set multiple secondary domain names. As shown in the figure:   To configure the tomcat file: Modify the server.xml File: The following configuration configures three containers with three different ports. Please note three points: ① port number: Connector port; ② container name: portservice ...

As a qualified programmer, how to make the code more concise and clear, and improve the coding speed. Today, follow me to learn the application of java 8 stream. Don't talk much nonsense, go straight to the point. Considering the following business scenario, there are four personnel information, and we need to count the names of personnel accor ...

brief introduction Before JDK11, the HTTP function of java was very weak, only HttpURLConnection was provided for HTTP connection, and it was very complex to use. So we usually use the third-party HTTP client (Apache HttpComponents or OkHttp) to make HTTP requests. Everything has changed in JDK11. In the java.net.http package, the latest HttpCl ...

Today, when testing phoenix's secondary index function, the following exception occurred when the index was created to write data: Caused by: org.apache.hadoop.hbase.client.RetriesExhaustedWithDetailsException: Failed 1 action: org.apache.phoenix.hbase.index.builder.IndexBuildingFailureException: Failed to build index for unexpected reason! ...