andriod 加载apk过程

Android apk默认加载过程

public final class LoadedApk {

    private static final String TAG = "LoadedApk";

    private final ActivityThread mActivityThread;
    private ApplicationInfo mApplicationInfo;
    final String mPackageName;
    private final String mAppDir;
    private final String mResDir;
    private final String[] mSharedLibraries;
    private final String mDataDir;
    private final String mLibDir;
    private final File mDataDirFile;
    private final ClassLoader mBaseClassLoader;
    private final boolean mSecurityViolation;
    private final boolean mIncludeCode;
    private final DisplayAdjustments mDisplayAdjustments = new DisplayAdjustments();
    Resources mResources;
    private ClassLoader mClassLoader;//默认加载器

    LoadedApk(ActivityThread activityThread) {
        mActivityThread = activityThread;
        mApplicationInfo = new ApplicationInfo();
        mApplicationInfo.packageName = "android";
        mPackageName = "android";
        mAppDir = null;
        mResDir = null;
        mSharedLibraries = null;
        mDataDir = null;
        mDataDirFile = null;
        mLibDir = null;
        mBaseClassLoader = null;
        mSecurityViolation = false;
        mIncludeCode = true;
        mClassLoader = ClassLoader.getSystemClassLoader();
        mResources = Resources.getSystem();
    }

                mClassLoader =
                    ApplicationLoaders.getDefault().getClassLoader(
                        zip, libraryPath, mBaseClassLoader);
                initializeJavaContextClassLoader();

                StrictMode.setThreadPolicy(oldPolicy);
            } else {
                if (mBaseClassLoader == null) {
                    mClassLoader = ClassLoader.getSystemClassLoader();
                } else {
                    mClassLoader = mBaseClassLoader;
                }
            }
            return mClassLoader;


ClassLoader.java

 protected ClassLoader() {
        this(getSystemClassLoader(), false);
    }
   static private class SystemClassLoader {
        public static ClassLoader loader = ClassLoader.createSystemClassLoader();
    }

    public static ClassLoader getSystemClassLoader() {
        return SystemClassLoader.loader;
    }

    private static ClassLoader createSystemClassLoader() {
        String classPath = System.getProperty("java.class.path", ".");

        // String[] paths = classPath.split(":");
        // URL[] urls = new URL[paths.length];
        // for (int i = 0; i < paths.length; i++) {
        // try {
        // urls[i] = new URL("file://" + paths[i]);
        // }
        // catch (Exception ex) {
        // ex.printStackTrace();
        // }
        // }
        //
        // return new java.net.URLClassLoader(urls, null);

        // TODO Make this a java.net.URLClassLoader once we have those?
        return new PathClassLoader(classPath, BootClassLoader.getInstance());
    }

参考：
http://blog.youkuaiyun.com/jiangwei0910410003/article/details/48104455