我网上下载了一个stdlib.jar文件，然后通过Bulid Path加入项目里面。现在我要调用这个jar文件下的类，不知道为什么抱错？ 新手求指点！
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If it can be imported, it means it is already on the classpath. You can try restarting eclipse.
It is estimated that it is not compiled properly. Because the error reported is "StdOut" not found, not "com.algs.stdlib.StdOut" not found.
Check automatic compilation and then clean the project
1, refresh the project, clean the project and then build it2, if it still doesn’t work, re-import the jar package and repeat the above steps
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If it can be imported, it means it is already on the classpath.
You can try restarting eclipse.
It is estimated that it is not compiled properly. Because the error reported is "StdOut" not found, not "com.algs.stdlib.StdOut" not found.
Check automatic compilation and then clean the project
1, refresh the project, clean the project and then build it
2, if it still doesn’t work, re-import the jar package and repeat the above steps