爲什麼maven會下載許多版本相同的依賴關係？

Question

我正在運行maven 3上的構建，並試圖下載同一個jar的許多不同版本，我甚至沒有將該jar指定爲依賴項。任何想法爲什麼這樣做？

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Answer 1

你會發現它實際上並沒有下載罐子，只是POM。我的猜想會被指定的版本不是一個固定的版本，並且maven正在挖掘可用版本以找出它應該使用哪個版本。

在依賴關係樹中的某個位置正在包含這個組件。你可以使用mvn dependency:tree找出在哪裏。當然，即使爲了顯示樹也需要下載所有的POM，但是現在已經有了它們:)