Avtiviti创建表时报错:Error getting a new connection. Cause: org.apache.commons.dbcp.SQLNestedException

Posted 2022-06-25 梦与光同行

问题描述

今天使用Acitivity创建ProcessEngineConfiguration对象时报错

错误如下

org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server.)
### Error getting a new connection.  Cause: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server.)
### Cause: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server.)

分析问题

1 有可能是mysql版本驱动的问题
2 有可能是配置错误问题
3 经我测试和查询网上的相关错误,大部分原因都是mysql版本问题或者配置错误,比如url确实参数,驱动8.0少加了cj,我是因为版本问题,我本地是8.0的数据库,但是jar是5.7的

解决问题

相关代码如下

<?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>

    <groupId>com.wyh</groupId>
    <artifactId>Activiti01</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.0.RELEASE</version>
    </parent>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <activiti.version>6.0.0</activiti.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
        <dependency>
            <groupId>org.activiti</groupId>
            <artifactId>activiti-spring-boot-starter-rest-api</artifactId>
            <version>$activiti.version</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.18</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

配置

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                    http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/contex
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx.xsd">


    <!--dbcp链接池-->
    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql:///activiti?serverTimezone=UTC"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
        <property name="maxActive" value="3"/>
        <property name="maxIdle" value="1"/>
    </bean>

    <!--在默认方式下 bean的id  固定为 processEngineConfiguration-->
    <bean id="processEngineConfiguration"
          class="org.activiti.engine.impl.cfg.StandaloneProcessEngineConfiguration">
        <!--配置数据库相关的信息-->
        <!--数据库驱动
        <property name="jdbcDriver" value="com.mysql.jdbc.Driver"/>-->
        <!--数据库链接
        <property name="jdbcUrl" value="jdbc:mysql:///activiti"/>-->
        <!--数据库用户名
        <property name="jdbcUsername" value="root"/>-->
        <!--数据库密码
        <property name="jdbcPassword" value="123456"/>-->
        <!--直接引用上面配置的链接池-->
        <property name="dataSource" ref="dataSource"/>
        <!--actviti数据库表在生成时的策略
        true - 如果数据库中已经存在相应的表，那么直接使用，
               如果不存在，那么会创建-->
        <property name="databaseSchemaUpdate" value="true"/>
    </bean>
</beans>

测试类

package com.wyh.test;

import org.activiti.engine.ProcessEngine;
import org.activiti.engine.ProcessEngines;
import org.activiti.engine.RepositoryService;
import org.junit.Test;

/**
 * @program: Activiti01
 * @description:
 * @author: 魏一鹤
 * @createDate: 2022-06-22 21:59
 **/

public class TestCreateTable 
    /**
     * 使用activiti提供的默认方式来创建mysql的表
     */
    @Test
    public void testCreateDbTable()
        //  需要使用avtiviti提供的工具类 ProcessEngines ,使用方法getDefaultProcessEngine
        //  getDefaultProcessEngine会默认从resources下读取名字为actviti.cfg.xml的文件
        //  创建processEngine时，就会创建mysql的表
        ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
        System.out.println(processEngine);
    

修改完之后再次启动测试

可以看到日志信息已经在创建表了

查看数据库 表已经正常创建