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Vincent Schut wrote: |
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> Hi all, |
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> |
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> when using java-config-2 from migration-overlay, it says 'deprecated' |
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> for all classpath related functions. I tried to find some more info on |
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> this, but couldn't find it. Maybe someone here can elaborate a bit more |
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> on how to work with java classpath (system and user) in the new gentoo |
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> java system? E.g. if I want to have some packages in my classpath, how |
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> would I do that using the new system? And how is this working |
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> together/conflicting with the current (old) items in /etc/env.d/ ? |
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> |
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> Cheers, |
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> Vincent. |
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> |
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|
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Setting a user and system wide classpath is deprecated because it can |
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cause several issues. |
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For example, say you put the classes from foo-2.0 on your classpath. |
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Then you emerge something that uses foo-1.0. This would because foo |
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would be slotted. However, when the build takes place, foo-2.0 could be |
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on the classpath before foo-1.0. It may have the same classnames and |
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whatnot, but different API. The differences between the APIs could then |
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cause the build to fail. |
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|
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Similarly, this scenario may also occur while running an application. |
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foo-1.0 might be expected, but foo-2.0 is on the classpath first... so |
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it may be missing methods, or have different behavior, and so on. |
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As for what to do instead of setting the classpath, it depends on what |
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you're trying to do. If you have an application that needs a certain |
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thing on the classpath, it is best to have a launcher script which sets |
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the right CLASSPATH. If you're building something that needs a |
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particular library, you should make the something be explicitly aware of |
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what it needs. In ant, this could mean having a lib directory with all |
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the jars (or symlinks to them), then you create a <path> that all your |
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<javac> and <java>'s use. This would really be dependent on how you're |
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building your project. |
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|
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This problem, and workarounds for it, are in the updated user |
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documentation |
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(https://svn.gentooexperimental.org/svn/java/migration/docs/java-user.html). |
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|
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Hope this clarifies, |
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|
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Josh |
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-- |
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