Android 解析APK包
它实现在ParsingPackageUtils类的静态方法parseDefault(ParseInput input, File file, @ParseFlags int parseFlags, @NonNull List
@NonNull
public static ParseResult<ParsingPackage> parseDefault(ParseInput input, File file,
@ParseFlags int parseFlags,
@NonNull List<PermissionManager.SplitPermissionInfo> splitPermissions,
boolean collectCertificates) {
ParseResult<ParsingPackage> result;
ParsingPackageUtils parser = new ParsingPackageUtils(false, null, null, splitPermissions,
new Callback() {
@Override
public boolean hasFeature(String feature) {
// Assume the device doesn't support anything. This will affect permission
// parsing and will force 1、新建 ParsingPackageUtils 实例 在这里设置的回调Callback的startParsingPackage() 方法，它是用来生成parseDefault()实际返回的对象类型。
2、调用新生成的ParsingPackageUtils 实例的parsePackage()得到ParseResult类型result。
3、根据参数 collectCertificates 来判断是否执行签名验证。可以参考Android APK文件的签名V2查找、验证，Android APK文件完整性验证
其中比较主要的是第二步，解析包得到包信息。
解析包
相关代码如下：
public ParseResult<ParsingPackage> parsePackage(ParseInput input, File packageFile,
int flags)
throws PackageParserException {
if (packageFile.isDirectory()) {
return parseClusterPackage(input, packageFile, flags);
} else {
return parseMonolithicPackage(input, packageFile, flags);
}
}
根据参数packageFile 是目录还是文件分别执行 parseClusterPackage(input, packageFile, flags) 还是 parseMonolithicPackage(input, packageFile, flags)。
像用户手动安装应用的时候，就是文件形式的。在开机时安装应用，则是目录的形式。
文件形式解析
private ParseResult<ParsingPackage> parseMonolithicPackage(ParseInput input, File apkFile,
int flags) throws PackageParserException {
final ParseResult<PackageLite> liteResult =
ApkLiteParseUtils.parseMonolithicPackageLite(input, apkFile, flags);
if (liteResult.isError()) {
return input.error(liteResult);
}
final PackageLite lite = liteResult.getResult();
if (mOnlyCoreApps && !lite.isCoreApp()) {
return input.error(INSTALL_PARSE_FAILED_ONLY_COREAPP_ALLOWED,
"Not a coreApp: " + apkFile);
}
final SplitAssetLoader assetLoader = new DefaultSplitAssetLoader(lite, flags);
try {
final ParseResult<ParsingPackage> result = parseBaseApk(input,
apkFile,
apkFile.getCanonicalPath(),
assetLoader, flags);
if (result.isError()) {
return input.error(result);
}
return input.success(result.getResult()
.setUse32BitAbi(lite.isUse32bitAbi()));
} catch (IOException e) {
return input.error(INSTALL_PARSE_FAILED_UNEXPECTED_EXCEPTION,
"Failed to get path: " + apkFile, e);
} finally {
IoUtils.closeQuietly(assetLoader);
}
}
首先通过ApkLiteParseUtils.parseMonolithicPackageLite(input, apkFile, flags)得到ParseResult类型liteResult。
其次生成一个DefaultSplitAssetLoader类对象。
通过parseBaseApk()得到ParseResult类对象result。
这里提到的lite.isUse32bitAbi()，该值是Manifest配置文件中标签 application 下的 use32bitAbi 属性值，如果不配置 默认为false。
解析得到apk文件的轻量级详情包
它实现在ApkLiteParseUtils类的parseMonolithicPackageLite()方法中：
/**
* Parse lightweight details about a single APK files.
*/
public static ParseResult<PackageLite> parseMonolithicPackageLite(ParseInput input,
File packageFile, int flags) {
Trace.traceBegin(TRACE_TAG_PACKAGE_MANAGER, "parseApkLite");
try {
final ParseResult<ApkLite> result = parseApkLite(input, packageFile, flags);
if (result.isError()) {
return input.error(result);
}
final ApkLite baseApk = result.getResult();
final String packagePath = packageFile.getAbsolutePath();
return input.success(
new PackageLite(packagePath, baseApk.getPath(), baseApk, null,
null, null, null, null, null, baseApk.getTargetSdkVersion()));
} finally {
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
}
}
可见这里主要是调用parseApkLite(input, packageFile, flags)得到ApkLite对象，然后将它封装到PackageLite对象中，并且返回。其中，PackageLite的构造函数中，使用了packagePath和baseApk.getPath()。packagePath是文件的绝对路径。baseApk.getPath()是什么呢，在这里也是文件的绝对路径。这俩值是赋值给了PackageLite的成员变量mPath和mBaseApkPath。看其注释，说它俩可能是不同的，因为移动或者重命名APK文件。
parseApkLite(input, packageFile, flags)主要接着调用parseApkLiteInner(ParseInput input, File apkFile, FileDescriptor fd, String debugPathName, int flags)，它再调用parseApkLite(ParseInput input, String codePath, XmlResourceParser parser, PackageParser.SigningDetails signingDetails)，主要解析的就是"AndroidManifest.xml"文件，但是它不会解析四大组件相关的属性信息。所以说它是轻量级。主要的解析信息都在parseApkLite(ParseInput input, String codePath, XmlResourceParser parser, PackageParser.SigningDetails signingDetails)中，看一下最后生成的ApkLite对象：
return input.success(
new ApkLite(codePath, packageSplit.first, packageSplit.second, isFeatureSplit,
configForSplit, usesSplitName, isSplitRequired, versionCode,
versionCodeMajor, revisionCode, installLocation, verifiers, signingDetails,
coreApp, debuggable, profilableByShell, multiArch, use32bitAbi,
useEmbeddedDex, extractNativeLibs, isolatedSplits, targetPackage,
overlayIsStatic, overlayPriority, minSdkVersion, targetSdkVersion,
rollbackDataPolicy));
这里面的值都是从"AndroidManifest.xml"文件中取得的，后面用到再说。
解析得到apk文件的解析包
它主要实现在parseBaseApk(ParseInput input, File apkFile, String codePath, SplitAssetLoader assetLoader, int flags)，
private ParseResult<ParsingPackage> parseBaseApk(ParseInput input, File apkFile,
String codePath, SplitAssetLoader assetLoader, int flags)
throws PackageParserException {
final String apkPath = apkFile.getAbsolutePath();
String volumeUuid = null;
if (apkPath.startsWith(MNT_EXPAND)) {
final int end = apkPath.indexOf('/', MNT_EXPAND.length());
volumeUuid = apkPath.substring(MNT_EXPAND.length(), end);
}
if (DEBUG_JAR) Slog.d(TAG, "Scanning base APK: " + apkPath);
final AssetManager assets = assetLoader.getBaseAssetManager();
final int cookie = assets.findCookieForPath(apkPath);
if (cookie == 0) {
return input.error(INSTALL_PARSE_FAILED_BAD_MANIFEST,
"Failed adding asset path: " + apkPath);
}
try (XmlResourceParser parser = assets.openXmlResourceParser(cookie,
ANDROID_MANIFEST_FILENAME)) {
final Resources res = new Resources(assets, mDisplayMetrics, null);
ParseResult<ParsingPackage> result = parseBaseApk(input, apkPath, codePath, res,
parser, flags);
if (result.isError()) {
return input.error(result.getErrorCode(),
apkPath + " (at " + parser.getPositionDescription() + "): "
+ result.getErrorMessage());
}
final ParsingPackage pkg = result.getResult();
if (assets.containsAllocatedTable()) {
final ParseResult<?> deferResult = input.deferError(
"Targeting R+ (version " + Build.VERSION_CODES.R + " and above) requires"
+ " the resources.arsc of installed APKs to be stored uncompressed"
+ " and aligned on a 4-byte boundary",
DeferredError.RESOURCES_ARSC_COMPRESSED);
if (deferResult.isError()) {
return input.error(INSTALL_PARSE_FAILED_RESOURCES_ARSC_COMPRESSED,
deferResult.getErrorMessage());
}
}
ApkAssets apkAssets = assetLoader.getBaseApkAssets();
boolean definesOverlayable = false;
try {
definesOverlayable = apkAssets.definesOverlayable();
} catch (IOException ignored) {
// Will fail if there's no packages in the ApkAssets, which can be treated as false
}
if (definesOverlayable) {
SparseArray<String> packageNames = assets.getAssignedPackageIdentifiers();
int size = packageNames.size();
for (int index = 0; index < size; index++) {
String packageName = packageNames.valueAt(index);
Map<String, String> overlayableToActor = assets.getOverlayableMap(packageName);
if (overlayableToActor != null && !overlayableToActor.isEmpty()) {
for (String overlayable : overlayableToActor.keySet()) {
pkg.addOverlayable(overlayable, overlayableToActor.get(overlayable));
}
}
}
}
pkg.setVolumeUuid(volumeUuid);
if ((flags & PARSE_COLLECT_CERTIFICATES) != 0) {
pkg.setSigningDetails(getSigningDetails(pkg, false));
} else {
pkg.setSigningDetails(SigningDetails.UNKNOWN);
}
return input.success(pkg);
} catch (Exception e) {
return input.error(INSTALL_PARSE_FAILED_UNEXPECTED_EXCEPTION,
"Failed to read manifest from " + apkPath, e);
}
}
首先得到解析包的volumeUuid，当然这得是它的安装路径是以"/mnt/expand/“开头。然后通过截取”/mnt/expand/“和它的下一个”/“之间的值作为volumeUuid。
assetLoader在这里是DefaultSplitAssetLoader对象，它是可以用来加载splits APK的，所以它可能对应有多个APK文件。这里通过文件路径apkPath找到AssetManager中对应的APK的位置。然后再通过cookie找到对应APK文件的"AndroidManifest.xml”，最后它的解析信息在XmlResourceParser类型的parser对象中。
其实解析APK文件也是挺复杂的，它的内容在AssetManager的getBaseAssetManager()中。它涉及到C++层的实现。这里只是简单描述一下相应过程，说通逻辑。
接着就是调用另一重载函数parseBaseApk()，来生成ParsingPackage对象。看一下它的实现：
private ParseResult<ParsingPackage> parseBaseApk(ParseInput input, String apkPath,
String codePath, Resources res, XmlResourceParser parser, int flags)
throws XmlPullParserException, IOException {
final String splitName;
final String pkgName;
ParseResult<Pair<String, String>> packageSplitResult =
ApkLiteParseUtils.parsePackageSplitNames(input, parser);
if (packageSplitResult.isError()) {
return input.error(packageSplitResult);
}
Pair<String, String> packageSplit = packageSplitResult.getResult();
pkgName = packageSplit.first;
splitName = packageSplit.second;
if (!TextUtils.isEmpty(splitName)) {
return input.error(
PackageManager.INSTALL_PARSE_FAILED_BAD_PACKAGE_NAME,
"Expected base APK, but found split " + splitName
);
}
final TypedArray manifestArray = res.obtainAttributes(parser, R.styleable.AndroidManifest);
try {
final boolean isCoreApp =
parser.getAttributeBooleanValue(null, "coreApp", false);
final ParsingPackage pkg = mCallback.startParsingPackage(
pkgName, apkPath, codePath, manifestArray, isCoreApp);
final ParseResult<ParsingPackage> result =
parseBaseApkTags(input, pkg, manifestArray, res, parser, flags);
if (result.isError()) {
return result;
}
return input.success(pkg);
} finally {
manifestArray.recycle();
}
}
ApkLiteParseUtils.parsePackageSplitNames(input, parser)是为了解析"package"、"split"属性，解析完之后，将对应值放在Pair里。
接下里会调用回调mCallback.startParsingPackage()方法，我们返回到ParsingPackageUtils的定义处。可知，它的实际类型是ParsingPackageImpl对象。
接着调用parseBaseApkTags(input, pkg, manifestArray, res, parser, flags)来得到具体的解析包对象。
private ParseResult<ParsingPackage> parseBaseApkTags(ParseInput input, ParsingPackage pkg,
TypedArray sa, Resources res, XmlResourceParser parser, int flags)
throws XmlPullParserException, IOException {
ParseResult<ParsingPackage> sharedUserResult = parseSharedUser(input, pkg, sa);
if (sharedUserResult.isError()) {
return sharedUserResult;
}
pkg.setInstallLocation(anInteger(PARSE_DEFAULT_INSTALL_LOCATION,
R.styleable.AndroidManifest_installLocation, sa))
.setTargetSandboxVersion(anInteger(PARSE_DEFAULT_TARGET_SANDBOX,
R.styleable.AndroidManifest_targetSandboxVersion, sa))
/* Set the global "on SD card" flag */
.setExternalStorage((flags & PARSE_EXTERNAL_STORAGE) != 0);
boolean foundApp = false;
final int depth = parser.getDepth();
int type;
while ((type = parser.next()) != XmlPullParser.END_DOCUMENT
&& (type != XmlPullParser.END_TAG
|| parser.getDepth() > depth)) {
if (type != XmlPullParser.START_TAG) {
continue;
}
String tagName = parser.getName();
final ParseResult result;
// has special logic, so it's handled outside the general method
if (TAG_APPLICATION.equals(tagName)) {
if (foundApp) {
if (RIGID_PARSER) {
result = input.error(" has more than one " );
} else {
Slog.w(TAG, " has more than one " );
result = input.success(null);
}
} else {
foundApp = true;
result = parseBaseApplication(input, pkg, res, parser, flags);
}
} else {
result = parseBaseApkTag(tagName, input, pkg, res, parser, flags);
}
if (result.isError()) {
return input.error(result);
}
}
if (!foundApp && ArrayUtils.size(pkg.getInstrumentations()) == 0) {
ParseResult<?> deferResult = input.deferError(
" does not contain an or " ,
DeferredError.MISSING_APP_TAG);
if (deferResult.isError()) {
return input.error(deferResult);
}
}
…………
return input.success(pkg);
}
可以看到这里主要是manifest文件中"application"标签和同级其他标签下的属性和标签。"application"标签下的主要是调用parseBaseApplication(input, pkg, res, parser, flags)，和"application"标签同级的使用parseBaseApkTag(tagName, input, pkg, res, parser, flags)解析。
在这里parseBaseApplication(input, pkg, res, parser, flags)就会将四大组件的信息都解析出来。
这样执行完毕，就将解析包信息都放在ParsingPackageImpl对象中。
目录形式解析
所谓以目录形式解析，就是给了一个文件是目录，安装文件包括在它包括的文件中。
看下它的实现：
private ParseResult<ParsingPackage> parseClusterPackage(ParseInput input, File packageDir,
int flags) {
final ParseResult<PackageLite> liteResult =
ApkLiteParseUtils.parseClusterPackageLite(input, packageDir, 0);
if (liteResult.isError()) {
return input.error(liteResult);
}
final PackageLite lite = liteResult.getResult();
if (mOnlyCoreApps && !lite.isCoreApp()) {
return input.error(INSTALL_PARSE_FAILED_ONLY_COREAPP_ALLOWED,
"Not a coreApp: " + packageDir);
}
// Build the split dependency tree.
SparseArray<int[]> splitDependencies = null;
final SplitAssetLoader assetLoader;
if (lite.isIsolatedSplits() && !ArrayUtils.isEmpty(lite.getSplitNames())) {
try {
splitDependencies = SplitAssetDependencyLoader.createDependenciesFromPackage(lite);
assetLoader = new SplitAssetDependencyLoader(lite, splitDependencies, flags);
} catch (SplitAssetDependencyLoader.IllegalDependencyException e) {
return input.error(INSTALL_PARSE_FAILED_BAD_MANIFEST, e.getMessage());
}
} else {
assetLoader = new DefaultSplitAssetLoader(lite, flags);
}
try {
final File baseApk = new File(lite.getBaseApkPath());
final ParseResult<ParsingPackage> result = parseBaseApk(input, baseApk,
lite.getPath(), assetLoader, flags);
if (result.isError()) {
return input.error(result);
}
ParsingPackage pkg = result.getResult();
if (!ArrayUtils.isEmpty(lite.getSplitNames())) {
pkg.asSplit(
lite.getSplitNames(),
lite.getSplitApkPaths(),
lite.getSplitRevisionCodes(),
splitDependencies
);
final int num = lite.getSplitNames().length;
for (int i = 0; i < num; i++) {
final AssetManager splitAssets = assetLoader.getSplitAssetManager(i);
parseSplitApk(input, pkg, i, splitAssets, flags);
}
}
pkg.setUse32BitAbi(lite.isUse32bitAbi());
return input.success(pkg);
} catch (PackageParserException e) {
return input.error(INSTALL_PARSE_FAILED_UNEXPECTED_EXCEPTION,
"Failed to load assets: " + lite.getBaseApkPath(), e);
} finally {
IoUtils.closeQuietly(assetLoader);
}
}
先通过ApkLiteParseUtils.parseClusterPackageLite(input, packageDir, 0)得到PackageLite对象。
接着创建SplitAssetLoader对象。lite.isIsolatedSplits()来自基础APK的配置文件里的"isolatedSplits"属性值，默认为false。如果它设置为true，并且存在splite apk，则会构造SplitAssetDependencyLoader。它会构造split apk间的依赖关系，如果存在依赖，会在加载apk（这里主要是加载ID资源表）的时候，一起加载。
再通过parseBaseApk(input, baseApk, lite.getPath(), assetLoader, flags)得到ParsingPackage对象。
如果是split apk，会接着调用parseSplitApk(input, pkg, i, splitAssets, flags)。
得到APK目录相关的轻量级详情
看下ApkLiteParseUtils类的parseClusterPackageLite()方法：
/**
* Parse lightweight details about a directory of APKs.
*/
public static ParseResult<PackageLite> parseClusterPackageLite(ParseInput input,
File packageDir, int flags) {
final File[] files = packageDir.listFiles();
if (ArrayUtils.isEmpty(files)) {
return input.error(PackageManager.INSTALL_PARSE_FAILED_NOT_APK,
"No packages found in split");
}
// Apk directory is directly nested under the current directory
if (files.length == 1 && files[0].isDirectory()) {
return parseClusterPackageLite(input, files[0], flags);
}
String packageName = null;
int versionCode = 0;
final ArrayMap<String, ApkLite> apks = new ArrayMap<>();
Trace.traceBegin(TRACE_TAG_PACKAGE_MANAGER, "parseApkLite");
try {
for (File file : files) {
if (isApkFile(file)) {
final ParseResult<ApkLite> result = parseApkLite(input, file, flags);
if (result.isError()) {
return input.error(result);
}
final ApkLite lite = result.getResult();
// Assert that all package names and version codes are
// consistent with the first one we encounter.
if (packageName == null) {
packageName = lite.getPackageName();
versionCode = lite.getVersionCode();
} else {
if (!packageName.equals(lite.getPackageName())) {
return input.error(PackageManager.INSTALL_PARSE_FAILED_BAD_MANIFEST,
"Inconsistent package " + lite.getPackageName() + " in " + file
+ "; expected " + packageName);
}
if (versionCode != lite.getVersionCode()) {
return input.error(PackageManager.INSTALL_PARSE_FAILED_BAD_MANIFEST,
"Inconsistent version " + lite.getVersionCode() + " in " + file
+ "; expected " + versionCode);
}
}
// Assert that each split is defined only oncuses-static-libe
if (apks.put(lite.getSplitName(), lite) != null) {
return input.error(PackageManager.INSTALL_PARSE_FAILED_BAD_MANIFEST,
"Split name " + lite.getSplitName()
+ " defined more than once; most recent was " + file);
}
}
}
} finally {
Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER);
}
final ApkLite baseApk = apks.remove(null);
return composePackageLiteFromApks(input, packageDir, baseApk, apks);
}
如果当前目录下面只有一个目录，会递归调用parseClusterPackageLite(ParseInput input, File packageDir, int flags)方法，并且会将这个目录作为参数传递。
如果目录下有多个以".apk"结尾的文件，则它为split apk安装形式。首先通过parseApkLite(input, file, flags)解析得到ApkLite对象，这个前面讲过。接下来，可以看到如果是split apk安装形式，基本apk是不用配置"split"属性值，其他apk则是需要配置不同的"split"属性值。并且会将"split"属性值和ApkLite对象放入ArrayMap
接下来会调用composePackageLiteFromApks(input, packageDir, baseApk, apks)，最后它会调用composePackageLiteFromApks( ParseInput input, File packageDir, ApkLite baseApk, ArrayMap
public static ParseResult<PackageLite> composePackageLiteFromApks(
ParseInput input, File packageDir, ApkLite baseApk,
ArrayMap<String, ApkLite> splitApks, boolean apkRenamed) {
if (baseApk == null) {
return input.error(PackageManager.INSTALL_PARSE_FAILED_BAD_MANIFEST,
"Missing base APK in " + packageDir);
}
// Always apply deterministic ordering based on splitName
final int size = ArrayUtils.size(splitApks);
String[] splitNames = null;
boolean[] isFeatureSplits = null;
String[] usesSplitNames = null;
String[] configForSplits = null;
String[] splitCodePaths = null;
int[] splitRevisionCodes = null;
if (size > 0) {
splitNames = new String[size];
isFeatureSplits = new boolean[size];
usesSplitNames = new String[size];
configForSplits = new String[size];
splitCodePaths = new String[size];
splitRevisionCodes = new int[size];
splitNames = splitApks.keySet().toArray(splitNames);
Arrays.sort(splitNames, sSplitNameComparator);
for (int i = 0; i < size; i++) {
final ApkLite apk = splitApks.get(splitNames[i]);
usesSplitNames[i] = apk.getUsesSplitName();
isFeatureSplits[i] = apk.isFeatureSplit();
configForSplits[i] = apk.getConfigForSplit();
splitCodePaths[i] = apkRenamed ? new File(packageDir,
splitNameToFileName(apk)).getAbsolutePath() : apk.getPath();
splitRevisionCodes[i] = apk.getRevisionCode();
}
}
final String codePath = packageDir.getAbsolutePath();
final String baseCodePath = apkRenamed ? new File(packageDir,
splitNameToFileName(baseApk)).getAbsolutePath() : baseApk.getPath();
return input.success(
new PackageLite(codePath, baseCodePath, baseApk, splitNames, isFeatureSplits,
usesSplitNames, configForSplits, splitCodePaths, splitRevisionCodes,
baseApk.getTargetSdkVersion()));
}
这里主要是处理split apk的多个文件的情况，这里注意的一点splitCodePath的名字会根据参数apkRenamed 来赋不同的值，如果apkRenamed 为true，则值为目录 + “split_” + splitName + “.apk”；如果为false，则为文件的路径名。
同样在为baseCodePath 赋值时，apkRenamed 为true，则值为目录 + “base.apk”；如果为false，则为文件的路径名。
在这里codePath 和 baseCodePath 的值是不同的，codePath为目录名，baseCodePath 为基本apk文件路径。它俩值分别对应PackageLite对象的成员mPath、mBaseApkPath。
这样就生成了PackageLite对象。
解析得到解析包对象
实现在parseBaseApk(ParseInput input, File apkFile, String codePath, SplitAssetLoader assetLoader, int flags)中，该方法在前面说过，在这里不同的是，codePath是目录，不是安装文件。
解析包ParsingPackageImpl对象
从前面知道，最终得到的解析包是ParsingPackageImpl对象，它里面包含所有解析出来的信息。看一下它的初始化函数：
@VisibleForTesting
public ParsingPackageImpl(@NonNull String packageName, @NonNull String baseApkPath,
@NonNull String path, @Nullable TypedArray manifestArray) {
this.packageName = TextUtils.safeIntern(packageName);
this.mBaseApkPath = baseApkPath;
this.mPath = path;
if (manifestArray != null) {
versionCode = manifestArray.getInteger(R.styleable.AndroidManifest_versionCode, 0);
versionCodeMajor = manifestArray.getInteger(
R.styleable.AndroidManifest_versionCodeMajor, 0);
setBaseRevisionCode(
manifestArray.getInteger(R.styleable.AndroidManifest_revisionCode, 0));
setVersionName(manifestArray.getNonConfigurationString(
R.styleable.AndroidManifest_versionName, 0));
setCompileSdkVersion(manifestArray.getInteger(
R.styleable.AndroidManifest_compileSdkVersion, 0));
setCompileSdkVersionCodename(manifestArray.getNonConfigurationString(
R.styleable.AndroidManifest_compileSdkVersionCodename, 0));
setIsolatedSplitLoading(manifestArray.getBoolean(
R.styleable.AndroidManifest_isolatedSplits, false));
}
}
在这里，我们知道mBaseApkPath 和mPath 的区别了，在用目录形式的解析时，mPath 是包含apk文件的目录。它里面包含特别多的成员变量和方法。在这里，我们知道它是从以上哪些函数中得到的，等以后使用到，就去这些函数中查找。
总结
解析apk包信息时，一种是通过apk文件作为参数解析，另外一种是通过apk文件所在目录作为参数来解析。
解析出来的类对象是ParsingPackageImpl类型的，它主要解析的是"AndroidManifest.xml"文件，类对象的成员也主要对应配置文件的属性和值。