Porting https://github.com/Activiti/Activiti/commit/2313f8ad979716efff89ea0b1524d7fe72b87a9f to v6

modules/activiti-spring-boot/spring-boot-starters/activiti-spring-boot-starter-basic/src/main/java/org/activiti/spring/boot/AbstractProcessEngineAutoConfiguration.java

@@ -96,6 +96,13 @@ public abstract class AbstractProcessEngineAutoConfiguration
     conf.setMailServerUseSSL(activitiProperties.isMailServerUseSsl());
     conf.setMailServerUseTLS(activitiProperties.isMailServerUseTls());
 
+    if (activitiProperties.getCustomMybatisMappers() != null) {
+      conf.setCustomMybatisMappers(getCustomMybatisMapperClasses(activitiProperties.getCustomMybatisMappers()));
+    }
+
+    if (activitiProperties.getCustomMybatisXMLMappers() != null) {
+      conf.setCustomMybatisXMLMappers(new HashSet<String>(activitiProperties.getCustomMybatisXMLMappers()));
+    }
 
     if (activitiProperties.getCustomMybatisMappers() != null) {
       conf.setCustomMybatisMappers(getCustomMybatisMapperClasses(activitiProperties.getCustomMybatisMappers()));
@@ -125,6 +132,19 @@ public abstract class AbstractProcessEngineAutoConfiguration
     return mybatisMappers;
   }
 
+  private Set<Class<?>> getCustomMybatisMapperClasses(List<String> customMyBatisMappers) {
+    Set<Class<?>> mybatisMappers = new HashSet<Class<?>>();
+    for (String customMybatisMapperClassName : customMyBatisMappers) {
+      try {
+        Class customMybatisClass = Class.forName(customMybatisMapperClassName);
+        mybatisMappers.add(customMybatisClass);
+      } catch (ClassNotFoundException e) {
+        throw new IllegalArgumentException("Class " + customMybatisMapperClassName + " has not been found.", e);
+      }
+    }
+    return mybatisMappers;
+  }
+
 
   private String defaultText(String deploymentName, String deploymentName1) {
     if (StringUtils.hasText(deploymentName))

modules/activiti-spring-boot/spring-boot-starters/activiti-spring-boot-starter-basic/src/main/java/org/activiti/spring/boot/ActivitiProperties.java

@@ -17,6 +17,9 @@ import java.util.List;
 
 import org.springframework.boot.context.properties.ConfigurationProperties;
 
+import java.util.List;
+import java.util.Set;
+
 /**
  * @author Josh Long
  * @author Joram Barrez
@@ -208,6 +211,7 @@ public class ActivitiProperties {
 	public void setMailServerUseTls(boolean mailServerUseTls) {
 		this.mailServerUseTls = mailServerUseTls;
 	}
+
   public List<String> getCustomMybatisMappers() {
     return customMybatisMappers;
   }
@@ -223,5 +227,4 @@ public class ActivitiProperties {
   public void setCustomMybatisXMLMappers(List<String> customMybatisXMLMappers) {
     this.customMybatisXMLMappers = customMybatisXMLMappers;
   }
-	
 }