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在我的 RCP 应用程序中，我使用 Wea​​vingHook 服务在加载时修改第三方类。我无法对第三方代码进行任何更改，因此我的编织实现必须按原样使用。

除了一个问题，我让它工作。对于我制作的其中一个模块，我实例化了一个内部类。它必须是内部类，因为它依赖于在其中一个超类中定义的内部类。

现在，当第三方代码加载修改后的类时，它的类路径上没有内部类的文件，这仅在我实现编织的插件中可用。如果第三方插件声明了 buddy 策略registered，我可以在清单中添加Eclipse-RegisterBuddy指令，但事实并非如此。

是否有某种编织方法可以使修改后的类能够访问通过二进制编织添加的内部匿名类？

我能想到的唯一解决办法就是在二进制编织发生时，将内部类文件复制到第三方代码的bin/目录下。看起来像一个黑客，所以我希望有更好的方法。

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2 回答 2

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getDynamicImports()您可以在通过 WeavingHook 使用以下方法编织类时动态添加 Import-Package ：

wovenClass.getDynamicImports().add("my.package.to.import");

这个包显然应该由另一个包导出。

于 2016-02-20T15:08:39.317 回答
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这是一个可行的解决方案，将内部类的类文件复制到包含编织目标的第三方插件的 bin/ 目录中。如果有人知道这样做的不那么老套的方法，请发布单独的答案。

编辑：使原始解决方案更通用，发现正在编织的类的所有内部类文件，如果在那里丢失或大小不同，则将它们复制到编织目标插件。

public class Activator extends Plugin {

    ...

   public static final String CLASS_FILE_ROOT = "bin/";

/**
 * Binary weaving of a class file may result in the addition or modification of
 * inner class files in this plug-in which need to be placed on the classpath
 * of the plug-in containing the weave target. This method compares inner class
 * files for a given class in this plug-in with inner class files in the plug-in
 * that contains the weave target. Any inner class files missing from the weave
 * target or with a different size than the corresponding file in this plug-in
 * are copied to the appropriate package directory in the weave target plug-in.
 * 
 * @param bundle the bundle of the class being woven
 * @param className the fully qualified name of the class being woven
 * @return true if no errors were encountered in copying the inner class files
 */
private boolean checkInnerClassFileSync(Bundle bundle, String className) {
    className = className.replaceAll("\\.", "/");
    String classDir = CLASS_FILE_ROOT + className.substring(
            0, FilenameUtils.indexOfLastSeparator(className));
    for (String innerClass : getInnerClassNames(classDir, FilenameUtils.getName(className))) {
        try {
            URL srcUrl = getBundle().getEntry(classDir + "/" + innerClass);
            File srcFile = new File(FileLocator.resolve(srcUrl).toURI());
            URL destUrl = bundle.getEntry(classDir);
            File destDir = new File(FileLocator.resolve(destUrl).toURI());
            File destFile = FileUtils.getFile(destDir, innerClass);
            if (srcFile.isFile() && (!destFile.exists() || destFile.length() != srcFile.length())) {
                FileUtils.copyFile(srcFile, destFile);
            }
        } catch (IOException | URISyntaxException e) {
            logger.log(Level.ERROR, "An error occurred while trying to copy an inner class file to the weave target bundle", e);
            return false;
        }
    }
    return true;
}

/**
 * Get the class files representing inner classes defined in a specified class and
 * found in a specified directory.
 * 
 * @param dir a sub-directory containing a class file for <code>className</code>
 * and possibly one or more class files representing inner classes defined in
 * <code>className</code>
 * @param className a class whose class file is found in <code>dir</code>
 * @return class files names representing every inner class defined in
 * <code>className</code> and found in <code>dir</code>.
 */
private String[] getInnerClassNames(String dir, String className) {
    List<String> classNames = new ArrayList<String>();
    try {
        File classDir = new File(FileLocator.resolve(getBundle().getEntry(dir)).toURI());
        for (String fName : classDir.list()) {
            Pattern p = Pattern.compile("^" + className + "\\$.+$");
            Matcher m = p.matcher(fName);
            if (m.matches()) {
                classNames.add(fName);
            }
        }
        return classNames.toArray(new String[0]);
    } catch (URISyntaxException | IOException e) {
        logger.log(Level.ERROR, "An error occured while scanning for inner class files", e);
        return classNames.toArray(new String[0]);
    }
}    

    ....

}
于 2016-02-20T21:59:22.670 回答