1. Eclipse 中在线安装 Activiti 插件
Name：Activiti BPMN 2.0 designer
Location：http://activiti.org/designer/update/
2. 问题修复
- 安装错误：
Cannot complete the install because one or more required items could not be found. Software being installed: Activiti Eclipse BPMN 2.0 Designer 5.18.0.201508100929 (org.activiti.designer.feature.feature.group 5.18.0.201508100929) Missing requirement: Activiti Eclipse BPMN 2.0 Designer 5.18.0.201508100929 (org.activiti.designer.feature.feature.group 5.18.0.201508100929) requires 'org.eclipse.emf.transaction 1.4.0' but it could not be found
- 解决方法：
将下载解压后的这三个文件（从 http://mvnrepository.com 搜索下载）拷贝到 eclipse 的 plugin 文件夹下即可解决上述问题。
org.eclipse.emf.transaction_1.4.0.v20100331-1738.jar
org.eclipse.emf.validation_1.7.0.201306111341.jar
org.eclipse.emf.workspace_1.5.1.v20120328-0001.jar
参考文章：
https://blog.csdn.net/dw_java08/article/details/8833982
