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java eclipse构建路径选项问题

[英]java eclipse build path options question

原文 2011-01-26 20:43:32 4 3 java/ eclipse/ buildpath/ eclipse-project-file

I have a question on Eclipse (I am using Helios). 我有一个关于Eclipse的问题（我正在使用Helios）。
When a project depends on various libraries, we add them to the classpath via the Build Path Dialog. 当项目依赖于各种库时，我们通过Build Path Dialog将它们添加到类路径中。
In the same dialog though, there is a tab for Projects (Required Projects on the build path). 但是，在同一个对话框中，有一个Projects选项卡（构建路径上的Required Projects）。
It is not clear to me, when someone would add such a reference from one project to another. 当有人将这样的参考从一个项目添加到另一个项目时，我不清楚。
I mean, if projectA needs functionality from projectB, then we can make a jar out of projectB and use it in projectA. 我的意思是，如果projectA需要来自projectB的功能，那么我们可以从projectB中创建一个jar并在projectA中使用它。
But when, would we add then, a reference from projectA to projectB, in order to need projectB in the build path of projectA? 但是，当我们添加从projectA到projectB的引用时，为了在projectA的构建路径中需要projectB？
Could someone please give an example? 有人可以举个例子吗？
Thank you! 谢谢！

3 个解决方案

Well, there are two reasons for depending on a project. 那么，取决于项目有两个原因。

You can "click through" to the source code of the other project when its code is invoked. 调用其代码时，可以“点击”其他项目的源代码。
If you're building and running the application in Eclipse for dev purposes, changes in the code will instantly be picked up. 如果您在Eclipse中构建并运行应用程序以用于开发目的，则会立即获取代码中的更改。

Update: I thought of a third one, possibly even better than the first two. 更新：我想到了第三个，甚至比前两个更好。 There is an "Order and Export" tab in the same screen, where you can select which elements of a project's classpath are exported. 在同一屏幕中有一个“Order and Export”选项卡，您可以在其中选择项目类路径的哪些元素被导出。 And what "exported" means here is exactly that if project B is configured to have project A as a dependency, then it will automatically add all the exported libraries from project A to its own classpath. “导出”的含义正是如果项目B配置为将项目A作为依赖项，那么它将自动将项目A中的所有导出库添加到其自己的类路径中。 So if project A has a lot of thrid party libraries, you don't have to manually add them to project B's classpath. 因此，如果项目A有很多第三方库，则不必手动将它们添加到项目B的类路径中。

“必需项目”允许您在项目之间声明依赖关系，而无需在每次对所依赖的项目进行更改时构建jar。

One (for me nice, for others; perhaps, blasphemous) use of the "Project Dependancy" is when you have a seperate project for unit tests. 一个（对我来说很好，对于其他人;也许是亵渎神明的）使用“项目依赖性”是指你有一个单独的单元测试项目。 Make the unit test project depend on the to-be-tested project. 使单元测试项目依赖于待测项目。 Of course, this is only nice if you are not a maven or hudson or blah, blah, blah user (like me). 当然，如果你不是一个maven或者哈德森或者是等等，等等用户（就像我一样），那就太好了。 Not that blah, blah, blah are bad things. 不是说，等等，等等，是坏事。