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Implementation Principle of Spring AntPath Matcher

Links to the original text: https://my.oschina.net/iqoFil/blog/221620   Recently, looking at the Spring source code, the AntPatternMatcher class has appeared many times in the source code, which is used to match URL s.       About this kind of introduction, some of the code is borrowed from Apache Ant.       PathMatcher implementation for Ant-style path patterns. Examples are provided...

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Custom Authentication Security Plug-in in Ignite

After Ignite cluster is built, the application can access the cluster for various operations. But the default cluster has no security protection mechanism. Any application and client supporting JDBC can access the cluster as long as they know the IP address of the cluster node, which creates a certain security risk, which is sensitive to holding number. According to users, it is obviously unacceptable. Ignite itself has a simple security module, which provides an authentication mechanism based on username/password. However, in actual business...

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Hadoop Series - HDFS Java API

I. Brief Introduction To use the HDFS API, you need to import dependencies on hadoop-client. If it's a CDH version of Hadoop, you need to specify its warehouse address as well: <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> ...

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Ten Backend Notes 7: Friendship Micro Services and Registry

Microservice Registry Spring Cloud Eureka is used as the microservice registry. Registry Microservice Creation Module (omitted) Introducing dependency Add Spring Cloud version bindings to tensquare_parent <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>Finchley.M9</version> ...

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httpclient multithreaded crawler instance

In the process of researching security testing recently, I stumbled upon a loophole in a certain station, which did not need to be checked when accessing resources. The original limit on the number of times users accessed resources every day was gone. I want to use crawler to crawl more data, but the amount of data is too large, so I want to use multithreading to crawl. After the attempt, the script was rough, because I didn't really want to climb it. It is estimated that 100,000 data, 10 threads, 10,000 per thread, 100 data per time...

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shiro integrates jwt+redis

In the first two articles, we integrated shiro+jwt stateless permission validation, so that only tocken is stored in the front end, and the back end only verifies whether Tocken is legal. Consider the problem that it's not very friendly and safe for front-end users to quit on the APP side when we set the token expiration time. Two business models are for reference only: 1. In BS architecture, I need the front end to exit automatically in half an hour, so we can use tocken to expire and exit automatically. 2. On the app side, I...

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Talking about DAG Task Decomposition and Shuffle RDD

1. Dag Scheduler Analysis The Dag Scheduler function is mainly responsible for the decomposition and Task submission of each stage of RDD. Stage decomposition starts from finalStage, which triggers the Task scheduling process, and retrieves the parent stage. If the parent stage does not commit the Task, the missing parent stage is submitted in a loop. Each stage has a concept of a parent RDD that creates multiple tasks (Tasks) based on the number of partitions. Task scheduling is actually accomplished through Task Scheduler Imp. Task...

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The reason why the jvm crashes and outputs hs_err_pidxxx.log file exception

Today, when deploying an existing jar package executable file on top of the service, I suddenly found that there were several hs_err_pidxxxxx.log files in the same level directory of jar. Look at this file, the contents are as follows # # A fatal error has been detected by the Java Runtime Environment: # # SIGSEGV (0xb) at pc=0x00007f5a7617ce38, pid=5920, tid=0x00007f5a37cfc700 # # JRE version: Java(TM) SE Runtime Environment (8.0_221-b11) (build 1.8.0_221-b11) # Java VM: Java HotSpot(TM) 64-Bit Server VM (25.221-b11 mixed mode linux-amd64...