内容完全来自，《深入理解Android 卷II》。作为学习笔记。
1.SystemServer.java
IPackageManager pm = null;
//PKMS的核心 main
pm = PackageManagerService.main(context, installer,factoryTest != SystemServer.FACTORY_TEST_OFF, onlyCore);
//后续操作
firstBoot = pm.isFirstBoot();
pm.performBootDexOpt();//dex优化
pm.systemReady();//通知系统
2.PackageManagerService.java
main(){
//两个操作
new PackageManagerService();
ServerManager.addService();
}
//构造函数
public PackageManagerService(Context context, Installer installer,
boolean factoryTest, boolean onlyCore) {
mSettings = new Settings(context);
mSettings.addSharedUserLPw(“android.uid.system”,
Process.SYSTEM_UID, ApplicationInfo.FLAG_SYSTEM);
//最后调用Settings.java的addUserLPw，将Package的uid保存在mUserIds中，将系统Package的uid保存在mOtherUsersIds中
//……
WindowManager wm = (WindowManager)context.getSystemService(Context.WINDOW_SERVICE);
// 得到wm
Display d = wm.getDefaul；
d.getMetrics(mMetrics);
//当前显示屏
mHandlerThread.start();
//ThreadHandler对象，用于程序安装和卸载
readPermissions();
//—>readPermissionsFromXml()；读取/system/etc/permissions/下的文件，将XML的标签转换成对应的数据结构（XML->java）
//解析package*.xml(5个文件),建立并更新对应的数据结构
mRestoredSettings = mSettings.readLPw(sUserManager.getUsers(false),mSdkVersion, mOnlyCore);
//以下对system/framework下的文件jar,apk进行dex优化
boolean didDexOpt = false;
//……
if (didDexOpt) {
//到此，为真则清空缓存(new File(mDalvikCacheDir, fn)).delete();
//以下三个＊InstallerObserver,scanDirLI分别对三个文件夹进行监视并扫描apk:system/framework,system/app,vendor/app
//……
//scanDirLI比较关键，其中调用了scanPackageLI,把APK文件转换为java的数据结构Package。
//mOnlyCore用于控制是否扫描非系统Package
if(!mOnlyCore){
//扫描data/app ,data/app_private
}
//汇总并更新和Permisson相关信息
updatePermissionsLPw(null, null, UPDATE_PERMISSIONS_ALL
| (regrantPermissions
? (UPDATE_PERMISSIONS_REPLACE_PKG|UPDATE_PERMISSIONS_REPLACE_ALL)
: 0));
// 写到package*.xml
mSettings.writeLPr();
}
3.PackageManagerService.java
private PackageParser.Package scanPackageLI(File scanFile,
int parseFlags, int scanMode, long currentTime, UserHandle user) {
//PackageParser.java,负责apk文件的解析，解析apk中的AndroidManifest.xml,
final PackageParser.Package pkg = pp.parsePackage(scanFile,
scanPath, mMetrics, parseFlags);
//再次调用同名函数
PackageParser.Package scannedPkg = scanPackageLI(pkg, parseFlags, scanMode
| SCAN_UPDATE_SIGNATURE, currentTime, user);
}
private PackageParser.Package scanPackageLI(PackageParser.Package pkg,
int parseFlags, int scanMode, long currentTime, UserHandle user) {
//单独处理了”android”的Package，与之对应的apk为framework-res.apk
if (pkg.packageName.equals(“android”)) {
//……ChooseActivity->ResolveActivity主要
}
synchronized (mPackages) {
//uses-librarie in mShareLibraries ?
if (pkg.usesLibraries != null || pkg.usesOptionalLibraries != null)
//SharedUserSettings
if (pkg.mSharedUserId != null)
// Check if we are renaming from an original package name.
if (pkg.mOriginalPackages != null)
// Just create the setting
pkgSetting = mSettings.getPackageLPw(pkg, origPackage, realName, suid, destCodeFile,
destResourceFile, pkg.applicationInfo.nativeLibraryDir,
pkg.applicationInfo.flags, user, false);
//check the sigature
if (!verifySignaturesLP(pkgSetting, pkg))
// Verify that this new package doesn’t have any content providers that conflict with existing packages.
if ((scanMode&SCAN_NEW_INSTALL) != 0)
//adopt ownership of permissions
if (pkg.mAdoptPermissions != null)
//set pkg.applicationInfo.dataDir
File dataPath;
pkg.applicationInfo.dataDir = dataPath.getPath();
//处理native动态库，从apk中解压复制到对应目录
if (pkg.applicationInfo.nativeLibraryDir != null)
//四大组件登记到PKMS内部的财产管理对象中
synchronized (mPackages) {
//……
｝
}
