diff --git a/app/src/main/java/io/legado/app/help/JsExtensions.kt b/app/src/main/java/io/legado/app/help/JsExtensions.kt
index 8d54ac21c..d321f57fb 100644
--- a/app/src/main/java/io/legado/app/help/JsExtensions.kt
+++ b/app/src/main/java/io/legado/app/help/JsExtensions.kt
@@ -33,11 +33,11 @@ object JsExtensions {
         return EncoderUtils.base64Encode(str)
     }
 
-    fun strToMd5By32(str: String?): String? {
+    fun strToMd5By32(str: String): String? {
         return MD5Utils.strToMd5By32(str)
     }
 
-    fun strToMd5By16(str: String?): String? {
+    fun strToMd5By16(str: String): String? {
         return MD5Utils.strToMd5By16(str)
     }
 
diff --git a/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt b/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt
index 831714667..b4bb0276e 100644
--- a/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt
+++ b/app/src/main/java/io/legado/app/model/analyzeRule/AnalyzeRule.kt
@@ -580,11 +580,11 @@ class AnalyzeRule(private var book: BaseBook? = null) {
         return EncoderUtils.base64Encode(str)
     }
 
-    fun strToMd5By32(str: String?): String? {
+    fun strToMd5By32(str: String): String? {
         return MD5Utils.strToMd5By32(str)
     }
 
-    fun strToMd5By16(str: String?): String? {
+    fun strToMd5By16(str: String): String? {
         return MD5Utils.strToMd5By16(str)
     }