Big data technology Spark Core

Spark Core of big data technology spark (3) 1: action reduce(func): use func function to gather all elements in RDD, first aggregate the data in the partition, and then aggregate the data between partitions. collect(): in the driver, all elements of the dataset are returned as arrays. count(): functio ...

Posted on Sat, 18 Jan 2020 00:39:06 -0500 by poltort

Talk about artemis's SesionConsumerFlowCreditMessage

order This article mainly studies EssionConsumerFlowCreditMessage of artemis SessionConsumerFlowCreditMessage activemq-artemis-2.11.0/artemis-core-client/src/main/java/org/apache/activemq/artemis/core/protocol/core/impl/wireformat/SessionConsumerFlowCreditMessage.java public class SessionConsumerFlowCreditMessage extends PacketImpl { privat ...

Posted on Thu, 16 Jan 2020 12:41:12 -0500 by itsinmyhead

MyBatis plug in development

1. Principle of mybatis plug-in MyBatis has plug-ins involved in the creation of four objects. The plug-in can use the dynamic proxy mechanism to wrap the target object layer by layer, and achieve the effect of intercepting before the target object executes the target method. When creating four object ...

Posted on Thu, 16 Jan 2020 10:20:49 -0500 by thirdeye

Java realizes SMS function through SMS platform

Preface This paper records the use of SMS platform built by China net, which needs to be registered before use. Here, only the use of SMS interface is recorded. 1. Login http://sms.webchinese.cn/User/?action=key Website registration. 2. Log in directly after registration. 3. After successful ...

Posted on Thu, 16 Jan 2020 04:27:50 -0500 by spyke01

Using Oltu Framework to Build Demo Project for OAuth

Apache's Oltu is the framework that implements OAuth Reference article: http://jinnianshilongnian.iteye.com/blog/2038646 https://blog.csdn.net/jing12062011/article/details/78147306   1. Build Maven Project Framework <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"       xsi:sc ...

Posted on Wed, 15 Jan 2020 11:14:22 -0500 by MNSarahG

Kafka use summary and production and consumption Demo implementation

What is kafka Kafka official website's own introduction is: a distributed flow platform can be supported.kafka official website kafka has three key capabilities: 1. Publish / subscribe record flow, similar to message queue and enterprise information system 2. Store the record stream in a fault-tolerant and persistent way 3. Con ...

Posted on Wed, 15 Jan 2020 07:25:05 -0500 by xydra

java notes collection

Related knowledge of set class The use of apache common tool classes Reference: https://juejin.im/post/5b1695595188257d37761e68 The difference between synchronized list and Vector Same points All thread safe The bottom layer is implemented by using arraysDifference (mainly the difference between ...

Posted on Wed, 15 Jan 2020 07:12:02 -0500 by livepjam

spring boot 2.x spring cloud Greenwich.SR1 gateway component zuul

spring boot 2.x spring cloud Greenwich.SR1 gateway component zuul Article directory spring boot 2.x spring cloud Greenwich.SR1 gateway component zuul 1. Project construction 1.1. Build a new project 'budget spring cloud Zul'. The pom file is as follows 1.2. Add the comments of gateway '@ EnableZu ...

Posted on Wed, 15 Jan 2020 06:18:12 -0500 by DeathStar

The mental process of online troubleshooting - too long GC time

One day, I suddenly received feedback from other group partners that calling one of our group's interfaces timed out. The information is as follows: cause: java.net.socketimeoutexception: read timed out So I quickly opened Postman to access the next interface, and the result was accessible. After commun ...

Posted on Tue, 14 Jan 2020 03:24:11 -0500 by gabo0303

Eureka service governance and configuration details

1, Eureka service governance mechanism Eureka service governance has three elements: service provider, service consumer and registration center. The relationship between the three elements is as follows: Service provider Service registration When the service provider starts, it will register the s ...

Posted on Tue, 14 Jan 2020 03:00:17 -0500 by Pryach