Programmer Group

Today's project, because of the use of spring asynchronous concurrent execution, this error occurred. And occasionally, especially when the project is just started, such problems may occur java.util.concurrent.ExecutionException: java.lang.ArrayIndexOutOfBoundsException: 3 at java.util.concurrent.FutureTask.report(FutureTask.java:122) ...

Spring Boot druid configuration rely on Add druid dependency to Spring Boot project <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>${druid.version}</version> </dependency> To configure spring.datasource.url= spring.datasource.username= spring.datasour ...

Example explanation In this example, slf4j-log4j12 is used to manage logs, and the logback classic dependency of spring boot start AMQP needs to be excluded to prevent conflicts. Key points of message queuing Producers: procedures for sending messages Consumer: a program that listens for and receives consumer messages Message: a stream of bin ...

Source code for this article: GitHub. Click here || GitEE. Click here 1. Application of Multiple Data Sources 1. Basic Description In relatively complex application services, configuring multiple data sources is a common phenomenon, such as: configuring a master-slave database to write data, and configuring a slave database to read data. This ...

                              . QT provides a class of QLayout for layout management, which can solve this problem well. Common layout management includes QVBoxLayout, QHBoxLayou ...

The responsibility chain pattern of Java design pattern Purchase approval project of school OA system: requirements are Traditional solution OA system approval, traditional design solution Basic introduction to responsibility chain mode Responsibility chain mode to solve OA system procurement approval Source co ...

Construction project For example, to create a spring MVC project, you need the start dependency of spring boot starter thymeleaf and spring boot starter web. For example, if you can upload files to the server, you need to add tags to the web.xml to do the relevant configuration, but in the sringboot project, it has been done for you automatica ...

Integrate Mybatis <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>2.1.2</version> </dependency> Steps: 1) . configure data source related properties (see Druid in the previous section) 2) . creating tables for data ...

Summary Online project publishing generally has the following schemes: Downtime release Blue green deployment Rolling deployment Grayscale release This kind of release is usually released at night or during major version upgrade. Because it needs to be stopped, now everyone is studying Devops scheme. Blue green deployment requires t ...

Java's dynamic Proxy mainly refers to the Proxy class under the java.lang.reflect package. The InvocationHandler interface under the same package will be used in the use process. 1. The proxy class provides a static method object newproxyinstance (classloader loader, class <? > [] interfaces, invocationhandler h) to generate proxy objects ...