derby.jar是引擎庫，必須的 For embedded databases. You always need this library for embedded environments. For client/server environments, you only need this library on the server.
工具庫
derbytools.jar: Required for running all the Derby tools (such as ij, dblook, and import/export).
derbyrun.jar: Executable jar file that can be used to start the Derby tools.
網絡服務端庫
如果是通過網絡連接Derby（非嵌入方式），那么需要這個jar。 derbynet.jar: Required to start the Derby Network Server.
網絡客戶端庫
derbyclient.jar: Required to use the Derby network client driver.
本地語言庫
derbyLocale_cs.jar Required to provide translated messages for the Czech locale.
derbyLocale_de_DE.jar Required to provide translated messages for the German locale.
derbyLocale_es.jar Required to provide translated messages for the Spanish locale.
derbyLocale_fr.jar Required to provide translated messages for the French locale.
derbyLocale_hu.jar Required to provide translated messages for the Hungarian locale.
derbyLocale_it.jar Required to provide translated messages for the Italian locale.
derbyLocale_ja_JP.jar Required to provide translated messages for the Japanese locale.
derbyLocale_ko_KR.jar Required to provide translated messages for the Korean locale.
derbyLocale_pl.jar Required to provide translated messages for the Polish locale.
derbyLocale_pt_BR.jar Required to provide translated messages for the Brazilian Portuguese locale.
derbyLocale_ru.jar Required to provide translated messages for the Russian locale.
derbyLocale_zh_CN.jar Required to provide translated messages for the Simplified Chinese locale.
derbyLocale_zh_TW.jar Required to provide translated messages for the Traditional Chinese locale.
