Java反射-类加载器检测新旧软件包中的已移动类

Question

I have been messing around with the class loader and other reflection methods, and it seems I have run into a weird bug. I used to have a file, lets say "ClassA.java" in one package, lets say "com.a". However, I had to the need to move it to package "com.b".

Now when I use this code to grab all classes in both packages,

ClassLoader[] classLoaders = new ClassLoader[] { ClasspathHelper.contextClassLoader(), ClasspathHelper.staticClassLoader() };

    String[] packagePrefixes = {"com.a", "com.b"};
    FilterBuilder filterBuilder = new FilterBuilder();
    for (String packagePrefix : packagePrefixes)
        filterBuilder.includePackage(packagePrefix);

    ConfigurationBuilder configurationBuiler = new ConfigurationBuilder()
            .setScanners(new SubTypesScanner(false), new ResourcesScanner())
            .setUrls(ClasspathHelper.forClassLoader(classLoaders))
            .filterInputsBy(filterBuilder);

    Set<Class<?>> allClasses = new Reflections(configurationBuiler).getSubTypesOf(Object.class);

The "ClassA.java" class appears twice in the allClasses set (Because the classes are ultimately different due to their different packages)

I tried cleaning and deleting/remaking the packages and files, but it seems to believe the file exists in both packages.

When I dragged the file into "com.b", eclipse gave me the normal pop-up and I did not check the "update fully qualified names in non-Java files".

I have a maven project. Any Ideas? Thanks!

Answer 1

此链接似乎与此问题有关： http : //blog.bjhargrave.com/2007/09/classforname-caches-defined-class-in.html

Answer 2

If this is a webapp, delete the server and recreate it. In my case, it was a webapp deployed from within Eclipse into a tomcat server. Nothing worked until I deleted the server and recreated it, then readded the webapp and started the server again. BOOM. Problem solved.

Some cache somewhere was not getting cleared. Clearing tomcat's the working directory was not enough.

Hope this helps someone out there.