导入新工程时报错：gen already exists but is not a source folder. Convert to a source folder or rename it....

解决办法：1. 右键点击工程，选择 "Properties"2. 选择左边的 "Java Build Path" 3. 打开 "Source" 标签面板4. 点击 "Add Folder..."5. 勾选 "gen" 文件夹，点击OK，点击YES，再点击OK

转载于:https://www.cnblogs.com/BEETLE-SY/p/3554726.html

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