PackageInfoAsAPK.java

package cn.edu.buaa.act.sdp.malwaredetector.entity;

import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.res.Resources;
import android.graphics.drawable.Drawable;
import android.util.DisplayMetrics;

import java.io.File;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/**
 * Created by yaodh on 2014/11/12.
 */
public class PackageInfoAsAPK {
    Context context;
    String apkPath;
    String appName;
    Drawable icon;
    String appVersion;
    long size;

    public PackageInfoAsAPK(Context context, String apkPath) {
        this.apkPath = apkPath;
        this.context = context;
        parseAPKInfo();
    }

    public String getApkPath() {
        return apkPath;
    }

    public String getAppName() {
        return appName;
    }

    public Drawable getIcon() {
        return icon;
    }

    public String getAppVersion() {
        return appVersion;
    }

    public long getSize() {
        return size;
    }

    private void parseAPKInfo() {

        // the size of apk
        File file = new File(apkPath);
        size = file.length();

        try {
            Class pkgParserClass = Class.forName("android.content.pm.PackageParser");
            Class[] typeArgs = new Class[]{String.class};
            Constructor pkgParserCst = pkgParserClass.getConstructor(typeArgs);
            Object[] valueArgs = new Object[]{apkPath};
            Object pkgParser = pkgParserCst.newInstance(valueArgs);
            DisplayMetrics metrics = new DisplayMetrics();
            metrics.setToDefaults();
            typeArgs = new Class[]{File.class, String.class, DisplayMetrics.class, Integer.TYPE};
            Method method = pkgParserClass.getDeclaredMethod("parsePackage", typeArgs);
            valueArgs = new Object[]{new File(apkPath), apkPath, metrics, 0};
            Object pkgParsePkg = method.invoke(pkgParser, valueArgs);
            Field appInfoField = pkgParsePkg.getClass().getDeclaredField("applicationInfo");
            ApplicationInfo info = (ApplicationInfo) appInfoField.get(pkgParsePkg);
            Class assetMagClass = Class.forName("android.content.res.AssetManager");
            Constructor assetMagCst = assetMagClass.getConstructor();
            Object assetMag = assetMagClass.newInstance();
            typeArgs = new Class[]{String.class};
            Method asset_addAssetPathMethod = assetMagClass.getDeclaredMethod("addAssetPath", typeArgs);
            valueArgs = new Object[]{apkPath};
            asset_addAssetPathMethod.invoke(assetMag, valueArgs);
            Resources resources = context.getResources();
            typeArgs = new Class[]{assetMag.getClass(), resources.getDisplayMetrics().getClass(), resources.getConfiguration().getClass()};
            Constructor resCst = Resources.class.getConstructor(typeArgs);
            valueArgs = new Object[]{assetMag, resources.getDisplayMetrics(), resources.getConfiguration()};
            resources = (Resources) resCst.newInstance(valueArgs);
            if (info.labelRes != 0) {
                appName = resources.getText(info.labelRes).toString();
            }
            if (info.icon != 0) {
                icon = resources.getDrawable(info.icon);
            }

        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (InvocationTargetException e) {
            e.printStackTrace();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (NoSuchFieldException e) {
            e.printStackTrace();
        }
    }

}