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app/src/main/java/com/hippo/ehviewer/util/PackageUtils.java

@@ -0,0 +1,26 @@
+package com.hippo.ehviewer.util;
+
+import android.content.Context;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
+import android.content.pm.Signature;
+
+public final class PackageUtils {
+
+    private static final String TAG = PackageUtils.class.getSimpleName();
+
+    public static String getSignature(Context context, String packageName) {
+        try {
+            PackageInfo pi = context.getPackageManager().getPackageInfo(packageName, PackageManager.GET_SIGNATURES);
+            Signature[] ss = pi.signatures;
+            if (ss != null && ss.length >= 1) {
+                return Utils.computeSHA1(ss[1].toByteArray());
+            } else {
+                Log.e(TAG, "Can't find signature in package " + packageName);
+            }
+        } catch (PackageManager.NameNotFoundException e) {
+            Log.e(TAG, "Can't find package " + packageName, e);
+        }
+        return null;
+    }
+}