Android 加载so 在android中怎样用Java加载解析so

//参数就是要加载的so文件名称
 public static void loadLibrary(String libName) {
         //通过调用Runtime下面的loadLibrary函数实现
         //函数有两个参数，参数1是加载的so文件名，参数2 类加载器。
        Runtime.getRuntime().loadLibrary(libName, VMStack.getCallingClassLoader());
    }

    /*
     * Searches for and loads the given shared library using the given ClassLoader.
     */
    void loadLibrary(String libraryName, ClassLoader loader) {
        if (loader != null) {
            //通过加载器去查找要加载的so文件名
            String filename = loader.findLibrary(libraryName);
            //查找失败
            if (filename == null) {
                // It's not necessarily true that the ClassLoader used
                // System.mapLibraryName, but the default setup does, and it's
                // misleading to say we didn't find "libMyLibrary.so" when we
                // actually searched for "liblibMyLibrary.so.so".
                throw new UnsatisfiedLinkError(loader + " couldn't find \"" +
                                               System.mapLibraryName(libraryName) + "\"");
            }
            //加载so文件名
            String error = doLoad(filename, loader);
            if (error != null) {
                throw new UnsatisfiedLinkError(error);
            }
            return;
        }
        
        String filename = System.mapLibraryName(libraryName);
        List<String> candidates = new ArrayList<String>();
        String lastError = null;
        //循环遍历文件路径
        for (String directory : mLibPaths) {
            //文件路径和文件名进行拼接
            String candidate = directory + filename;
            candidates.add(candidate);

            if (IoUtils.canOpenReadOnly(candidate)) {
                String error = doLoad(candidate, loader);
                if (error == null) {
                    return; // We successfully loaded the library. Job done.
                }
                lastError = error;
            }
        }

        if (lastError != null) {
            throw new UnsatisfiedLinkError(lastError);
        }
        throw new UnsatisfiedLinkError("Library " + libraryName + " not found; tried " + candidates);
    }

 private String doLoad(String name, ClassLoader loader) {
        // Android apps are forked from the zygote, so they can't have a custom LD_LIBRARY_PATH,
        // which means that by default an app's shared library directory isn't on LD_LIBRARY_PATH.

        // The PathClassLoader set up by frameworks/base knows the appropriate path, so we can load
        // libraries with no dependencies just fine, but an app that has multiple libraries that
        // depend on each other needed to load them in most-dependent-first order.

        // We added API to Android's dynamic linker so we can update the library path used for
        // the currently-running process. We pull the desired path out of the ClassLoader here
        // and pass it to nativeLoad so that it can call the private dynamic linker API.

        // We didn't just change frameworks/base to update the LD_LIBRARY_PATH once at the
        // beginning because multiple apks can run in the same process and third party code can
        // use its own BaseDexClassLoader.

        // We didn't just add a dlopen_with_custom_LD_LIBRARY_PATH call because we wanted any
        // dlopen(3) calls made from a .so's JNI_OnLoad to work too.

        // So, find out what the native library search path is for the ClassLoader in question...
        String ldLibraryPath = null;
        if (loader != null && loader instanceof BaseDexClassLoader) {
            ldLibraryPath = ((BaseDexClassLoader) loader).getLdLibraryPath();
        }
        // nativeLoad should be synchronized so there's only one LD_LIBRARY_PATH in use regardless
        // of how many ClassLoaders are in the system, but dalvik doesn't support synchronized
        // internal natives.
        synchronized (this) {
            return nativeLoad(name, loader, ldLibraryPath);
        }
    }