diff --git a/app/src/main/java/com/hippo/ehviewer/client/parser/GalleryDetailUrlParser.kt b/app/src/main/java/com/hippo/ehviewer/client/parser/GalleryDetailUrlParser.kt
index a7d611e6c..1a0a0521c 100644
--- a/app/src/main/java/com/hippo/ehviewer/client/parser/GalleryDetailUrlParser.kt
+++ b/app/src/main/java/com/hippo/ehviewer/client/parser/GalleryDetailUrlParser.kt
@@ -13,56 +13,32 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+package com.hippo.ehviewer.client.parser
 
-package com.hippo.ehviewer.client.parser;
-
-import androidx.annotation.Nullable;
-
-import com.hippo.ehviewer.client.EhUrl;
-import com.hippo.yorozuya.NumberUtils;
-
-import java.util.regex.Matcher;
-import java.util.regex.Pattern;
+import com.hippo.ehviewer.client.EhUrl
+import com.hippo.yorozuya.NumberUtils
+import java.util.regex.Pattern
 
 /**
- * Like http://exhentai.org/g/1234567/a1b2c3d4e5<br>
+ * Like http://exhentai.org/g/1234567/a1b2c3d4e5<br></br>
  */
-public final class GalleryDetailUrlParser {
+object GalleryDetailUrlParser {
+    private val URL_STRICT_PATTERN = Pattern.compile(
+        "https?://(?:" + EhUrl.DOMAIN_EX + "|" + EhUrl.DOMAIN_E + "|" + EhUrl.DOMAIN_LOFI + ")/(?:g|mpv)/(\\d+)/([0-9a-f]{10})",
+    )
+    private val URL_PATTERN = Pattern.compile("(\\d+)/([0-9a-f]{10})(?:[^0-9a-f]|$)")
 
-    private static final Pattern URL_STRICT_PATTERN = Pattern.compile(
-            "https?://(?:" + EhUrl.DOMAIN_EX + "|" + EhUrl.DOMAIN_E + "|" + EhUrl.DOMAIN_LOFI + ")/(?:g|mpv)/(\\d+)/([0-9a-f]{10})");
-
-    private static final Pattern URL_PATTERN = Pattern.compile(
-            "(\\d+)/([0-9a-f]{10})(?:[^0-9a-f]|$)");
-
-    @Nullable
-    public static Result parse(String url) {
-        return parse(url, true);
-    }
-
-    @Nullable
-    public static Result parse(String url, boolean strict) {
-        if (url == null) {
-            return null;
-        }
-
-        Pattern pattern = strict ? URL_STRICT_PATTERN : URL_PATTERN;
-        Matcher m = pattern.matcher(url);
-        if (m.find()) {
-            Result result = new Result();
-            result.gid = NumberUtils.parseLongSafely(m.group(1), -1L);
-            result.token = m.group(2);
-            if (result.gid < 0) {
-                return null;
-            }
-            return result;
+    fun parse(url: String?, strict: Boolean = true): Result? {
+        url ?: return null
+        val pattern = if (strict) URL_STRICT_PATTERN else URL_PATTERN
+        val m = pattern.matcher(url)
+        return if (m.find()) {
+            val gid = NumberUtils.parseLongSafely(m.group(1), 0).takeIf { it > 0 }
+            gid?.let { Result(it, m.group(2)!!) }
         } else {
-            return null;
+            null
         }
     }
 
-    public static class Result {
-        public long gid;
-        public String token;
-    }
+    class Result(val gid: Long, val token: String)
 }