前言
由于项目需求涉及到流程，自然而然就选择activiti作为流程管理。项目环境为springboot2.1.4release版本+JDK1.8.0_201，随后到maven中央仓库查找：activiti-spring-boot-starter发现了7.0GA稳定版本。心里一阵狂喜。因为之前项目使用时只是beta版本，但是还是非常方便，引入依赖即可使用。但是这次使用却出现了问题。意思大概是activiti-spring-boot-starter使用了比当前JDK更高的版本编译，生成的class文件当前jre虚拟机无法识别。activiti-spring-boot-starter均为7.x，因此我选择之前activiti提供的activiti-spring-boot-starter-basic6.0稳定版来整合。
开始整合
1.引入依赖
<dependency>
<groupId>org.activiti</groupId>
<artifactId>activiti-spring-boot-starter-basic</artifactId>
<version>6.0.0</version>
</dependency>
2.启动出现错误 GlobalAuthenticationConfigurerAdapter.class错误
org.springframework.beans.factory.BeanDefinitionStoreException : Failed to process import candidates for configuration class [com.xxx.xxx.xxx.xxxx]; nested exception is java.io.FileNotFoundException: class path resource [org/springframework/security/config/annotation/authentication/configurers/ GlobalAuthenticationConfigurerAdapter.class ] cannot be opened because it does not exist at org.springframework.context.annotation.ConfigurationClassParser.processImports(ConfigurationClassParser.java:599) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.context.annotation.ConfigurationClassParser.access$900(ConfigurationClassParser.java:108) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE] at
] ... xxx common frames omitted
解决： 这个是在 spring-boot-starter-security 依赖中的 属于安全配置类, 而 引入的activiti-spring-boot-starter-basic 依赖中存在了一个自动安全配置类, 两个安全配置, 所以排除掉 activiti-spring-boot-starter-basic中的安全配置类 SecurityAutoConfiguration , 在启动类配置 （注意不要导错包，正确的包为org.activiti.spring.boot.SecurityAutoConfiguration）:
import org.activiti.spring.boot.SecurityAutoConfiguration;
@SpringBootApplication(exclude = SecurityAutoConfiguration.class)
public class Application { public static void main(String[] args) {
SpringApplication.run(Application.class, args);
3.再次启动出现 EntityManagerFactory ' that could not be found.错误
Description:
Parameter 0 of method transactionManager in org.activiti.spring.boot.JpaProcessEngineAutoConfiguration$JpaConfiguration required a bean of type 'javax.persistence.EntityManagerFactory' that could not be found.
Action:
Consider defining a bean of type 'javax.persistence.EntityManagerFactory' in your configuration.
解决： activiti初始化表，操作数据库使用jpa，我们这里解决办法就是引入spring-data-jpa-starter自动配置 EntityManagerFactory。
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
4. 出现了依赖版本冲突的问题 persistence-api 包含一个1.0和2.2， 根据提示我们选择使用1.0
Description:
An attempt was made to call a method that does not exist. The attempt was made from the following location: org.hibernate.jpa.boot.internal.PersistenceUnitInfoDescriptor.getValidationMode( PersistenceUnitInfoDescriptor.java:88 )The following method did not exist: javax.persistence.spi.PersistenceUnitInfo.getValidationMode() Ljavax/persistence/ValidationMode; The method's class, javax.persistence.spi.PersistenceUnitInfo, is available from the following locations: jar:file:/D:/Program%20Files/apache-maven-3.6.0/localRepository/javax/persistence/persistence-api/1.0/persistence-api-1.0.jar !/javax/persistence/spi/PersistenceUnitInfo.class jar:file:/D:/Program%20Files/apache-maven-3.6.0/localRepository/javax/persistence/javax.persistence-api/2.2/javax.persistence-api-2.2.jar!/javax/persistence/spi/PersistenceUnitInfo.classIt was loaded from the following location: file:/D:/Program%20Files/apache-maven-3.6.0/localRepository/javax/persistence/persistence-api/1.0/persistence-api-1.0.jar
Action:
Correct the classpath of your application so that it contains a single, compatible version of javax.persistence.spi.PersistenceUnitInfo
解决：在pom文件里面我们直接依赖1.0版本，maven会选择直接依赖，解决其他间接依赖的版本冲突。
<!--解决依赖冲突，其他间接依赖了两个版本1.0和2.2的，我这里直接依赖1.0-->
<dependency>
<groupId>javax.persistence</groupId>
<artifactId>persistence-api</artifactId>
<version>1.0</version>
</dependency>
5. 我这里意外出现了异常，因为我的部分加@Entity注解的model类，没有标识，也就是加入主键的标识@ID，
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaConfiguration.class]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: No identifier specified for entity : com.xxx.xxx.xxx.xxx.xxx.exampleModel at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1778) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:593) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1105) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.6.RELEASE.jar:5.1.6.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE] at
... xx common frames omitted
解决：@EntityScan注解,选择符合规范的包
@SpringBootApplication(exclude = SecurityAutoConfiguration.class)
@EntityScan(basePackages = {"com.xxx.xxx.xxx.xxx.model"})
public class Application { public static void main(String[] args) {