遇到的问题
安装Activiti Designer插件的时候，发现eclipse报错，报错信息中包含：requires ‘bundle org.apache.commons.io 0.0.0’。
补充报错案例：安装Mybatis ****的eclipse插件，说缺少某个bundle
Cannot complete the install because one or more required items could not be found.
Software being installed: MyBatis Generator 1.3.5.201609070108 (org.mybatis.generator.feature.group 1.3.5.201609070108)
Missing requirement: MyBatis Generator UI Plugin 1.3.5.201609070108 (org.mybatis.generator.eclipse.ui 1.3.5.201609070108) requires ‘bundle org.eclipse.core.variables 3.2.800’ but it could not be found
Cannot satisfy dependency:
From: MyBatis Generator 1.3.5.201609070108 (org.mybatis.generator.feature.group 1.3.5.201609070108)
To: org.mybatis.generator.eclipse.ui [1.3.5.201609070108]
解决方案
org.apache.commons.io这个bundle的下载路径，最后找到了一个这个下载路径：
http://download.eclipse.org/tools/orbit/downloads/drops/R20150124073747/repository/
此路径中包含了eclipse的所有bundle的下载，然后在里面找到需要的bundle，勾选上，点安装就行了。