| EngineManager | EngineManager is a plugin to determine which engine to be used |
| InputLanguageManager | InputLanguageManager is a plugin to determine which input language to be used |
| QimsysAbstractIpcObject | Facilities for implementing the client and server sides of IPC communications paths |
| QimsysAbstractPluginObject | Base class of object for qimsys plugin system |
| QimsysApplicationManager | QimsysApplicationManager manages general infomation |
| QimsysCandidates | QimsysCandidates represents candidate list and index |
| QimsysConversionItem | QimsysConversionItem is data for each conversion items |
| QimsysConversionItemList | QList of QimsysConversionItem |
| QimsysConverter | An interface for converter plugins |
| QimsysEngine | QimsysEngine is an interface for conversion engine |
| QimsysKeyManager | This class manages key input |
| QimsysKeySequence | QimsysKeySequence is yet another QKeySequence |
| QimsysKeyWidget | QimsysKeyWidget is used to get key sequence |
| QimsysPlugin | QimsysPlugin is the base class for all qimsys plugins |
| QimsysPluginManager | QimsysPluginManager loads plugins |
| QimsysPreedit | QimsysPreedit represents preedit data and preedit area |
| QimsysPreeditItem | QimsysPreeditItem is data for each preedit items |
| QimsysPreeditItemList | QList of QimsysPreeditItem |
| QimsysSettingsWidget | Widget for plugin settings |
1.5.6