phoenix store sparkstreaming datagram java.lang.NullPointerException error

Version environment Spark: Spark version 2.2.0Phoenix: APACHE_PHOENIX-4.14.0-cdh5.14.2HBase: Version 1.2.0-cdh5.14.4JDK: java version "1.8.0_74"Java(TM) SE Runtime Environment (build 1.8.0_74-b02)Java HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode) Achieve goals: sparkstreaming receives the data from kafka, and writes the data to hba ...

Posted on Tue, 19 Nov 2019 14:14:06 -0500 by jake8

Spring connect mysql database error cannot load jdbc driver class' {driver} '

                The following error occurred when using Spring to connect mysql database: Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception isjava.sql.SQLException: Cannot load JDBC driver class '${driver}' The error details are as follows: Exception in thread "ma ...

Posted on Tue, 19 Nov 2019 13:19:48 -0500 by iPixel

Talk about the pullBatchSize of rocketmq

order In this paper, I just want to study the pullBatchSize of rocketmq pullBatchSize rocketmq-client-4.5.2-sources.jar!/org/apache/rocketmq/client/consumer/DefaultMQPushConsumer.java public class DefaultMQPushConsumer extends ClientConfig implements MQPushConsumer { private final InternalLogger log = ClientLogger.getLog(); //...... ...

Posted on Tue, 19 Nov 2019 12:01:52 -0500 by hc

A preliminary study of spring boot -- what does spring boot starter web do

Last article This article mainly discusses the dependencies introduced by springboot We all know that to make a web application with springboot, the first thing we need to do is to introduce related dependencies. There are two steps: 1. Add spring boot starter parent 2. Introduce spring boot starter Web So far, all the web dependencies have ...

Posted on Tue, 19 Nov 2019 04:50:09 -0500 by magaly

Hystrix of spring cloud: cluster fault tolerance framework

In the distributed environment, some dependent services may fail, affecting the stable operation of the system.Hystrix controls the interaction of components among distributed systems by adding delay threshold and fault-tolerant logic.Hystrix can achieve fault tolerance by isolating access points between services, stopping cascading failures be ...

Posted on Tue, 19 Nov 2019 02:43:04 -0500 by jsinker

Kafka Integrates Spring - Producer Configuration

Guide (Maven): <!--Journal--> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-api</artifactId> <version>1.7.22</version> </dependency> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12& ...

Posted on Mon, 18 Nov 2019 20:55:47 -0500 by kyme

25. springboot sends email

Although SMS verification is now the most popular and commonly used method of verification, email verification is still indispensable and still one of the necessary functions of the website. Any registration verification, forgetting password or sending marketing information to users can use the e-mail function. In the early stag ...

Posted on Mon, 18 Nov 2019 14:47:17 -0500 by Dennis Madsen

Using the Jacobo Maven plug-in to create code coverage reports

This blog post describes how we use the Jacobo Maven plug-in to create code coverage reports for unit and integration tests. Our construction requirements are as follows: When running tests, our build must create code coverage reports for unit and integration tests. Code coverage reports must be created in a separate directory. In other words, ...

Posted on Mon, 18 Nov 2019 02:51:19 -0500 by jannoy

ZooKeeper timeout exception

ZooKeeper timeout exceptions include two types: 1) client readTimeout causing connection loss; 2) server session timeout sessionTimeout causing client connection failure Client readTimeout causes connection loss The readTimeout of the ZooKeeper client cannot be set; its value is calculated based on the session timeout.The calculation rules are: ...

Posted on Sun, 17 Nov 2019 04:08:54 -0500 by Biocide

The difference between spring MVC @ controller and @ RestController annotations

Official documents:         @RestController is a stereotype annotation that combines @ResponseBody and @Controller. The @ RestController annotation is equivalent to the combination of @ ResponseBody + @ Controller.   1. If you just annotate the Controller with @ RestController Methods in the Controller cannot Return jsp pa ...

Posted on Sat, 16 Nov 2019 15:48:48 -0500 by itazev