Android5.0以上APP签名校验

public static String getSingInfo(String pkgName, Context c) {
try {
PackageInfo packageInfo = c.getPackageManager().getPackageInfo(pkgName, PackageManager.GET_SIGNATURES);
Signature[] signs = packageInfo.signatures;
Signature sign = signs[0];

return sign.toCharsString();
//          parseSignature(sign.toByteArray());
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

public static String showUninstallAPKSignatures(String apkPath) {
String PATH_PackageParser = "android.content.pm.PackageParser";
try {
//        // apk包的文件路径
//        // 这是一个Package 解释器, 是隐藏的
//        // 构造函数的参数只有一个, apk文件的路径
//        // PackageParser packageParser = new PackageParser(apkPath);
//        Class pkgParserCls = Class.forName(PATH_PackageParser);
//        Class[] typeArgs = new Class[1];
//        typeArgs[0] = String.class;
//        Constructor pkgParserCt = pkgParserCls.getConstructor(typeArgs);
//        Object[] valueArgs = new Object[1];
//        valueArgs[0] = apkPath;
//        Object pkgParser = pkgParserCt.newInstance(valueArgs);
//        Log.i(TAG, "pkgParser:" + pkgParser.toString());
//        // 这个是与显示有关的, 里面涉及到一些像素显示等等, 我们使用默认的情况
//        DisplayMetrics metrics = new DisplayMetrics();
//        metrics.setToDefaults();
//        // PackageParser.Package mPkgInfo = packageParser.parsePackage(new
//        // File(apkPath), apkPath,
//        // metrics, 0);
//        typeArgs = new Class[4];
//        typeArgs[0] = File.class;
//        typeArgs[1] = String.class;
//        typeArgs[2] = DisplayMetrics.class;
//        typeArgs[3] = Integer.TYPE;
//        Method pkgParser_parsePackageMtd = pkgParserCls.getDeclaredMethod(
//                "parsePackage", typeArgs);
//        valueArgs = new Object[4];
//        valueArgs[0] = new File(apkPath);
//        valueArgs[1] = apkPath;
//        valueArgs[2] = metrics;
//        valueArgs[3] = PackageManager.GET_SIGNATURES;

//以上方法在Android L以前可以用

Object pkgParser;
Class pkgParserCls = Class.forName(PATH_PackageParser);
Constructor<?> pkgParserCt;
Class<?>[] typeArgs = {String.class};
Object[] valueArgs = {apkPath};
Method pkgParser_parsePackageMtd;
Object pkgParserPkg;
if (Build.VERSION.SDK_INT >= 21) {
//noinspection NullArgumentToVariableArgMethod
Class[] cNull = null;
Object[] oNull = null;
pkgParserCt = pkgParserCls.getConstructor(cNull);
//noinspection NullArgumentToVariableArgMethod
pkgParser = pkgParserCt.newInstance(oNull);
typeArgs = new Class[2];
typeArgs[0] = File.class;
typeArgs[1] = Integer.TYPE;
pkgParser_parsePackageMtd = pkgParserCls.getDeclaredMethod("parsePackage", typeArgs);

valueArgs = new Object[2];
valueArgs[0] = new File(apkPath);
valueArgs[1] = 0;

pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser, valueArgs);
} else {
pkgParserCt = pkgParserCls.getConstructor(typeArgs);
pkgParser = pkgParserCt.newInstance(valueArgs);

typeArgs = new Class<?>[]{File.class, String.class, DisplayMetrics.class, int.class};
pkgParser_parsePackageMtd = pkgParserCls.getDeclaredMethod("parsePackage", typeArgs);

DisplayMetrics metrics = new DisplayMetrics();
metrics.setToDefaults();

valueArgs = new Object[4];
valueArgs[0] = new File(apkPath);
valueArgs[1] = apkPath;
valueArgs[2] = metrics;
valueArgs[3] = 0;

pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser, valueArgs);
}
//        Object pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser,
//                valueArgs);

typeArgs = new Class[2];
typeArgs[0] = pkgParserPkg.getClass();
typeArgs[1] = Integer.TYPE;
Method pkgParser_collectCertificatesMtd = pkgParserCls
.getDeclaredMethod("collectCertificates", typeArgs);
valueArgs = new Object[2];
valueArgs[0] = pkgParserPkg;
valueArgs[1] = PackageManager.GET_SIGNATURES;
pkgParser_collectCertificatesMtd.invoke(pkgParser, valueArgs);
// 应用程序信息包, 这个公开的, 不过有些函数, 变量没公开
Field packageInfoFld = pkgParserPkg.getClass().getDeclaredField(
"mSignatures");
Signature[] info = (Signature[]) packageInfoFld.get(pkgParserPkg);

Log.i(TAG, info[0].toCharsString());
return info[0].toCharsString();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}