diff --git a/app/src/main/java/io/legado/app/constant/AppConst.kt b/app/src/main/java/io/legado/app/constant/AppConst.kt
index 89a1d204f..863f9e27a 100644
--- a/app/src/main/java/io/legado/app/constant/AppConst.kt
+++ b/app/src/main/java/io/legado/app/constant/AppConst.kt
@@ -1,5 +1,8 @@
 package io.legado.app.constant
 
+import io.legado.app.App
+import io.legado.app.R
+
 object AppConst {
     const val channelIdDownload = "channel_download"
     const val channelIdReadAloud = "channel_read_aloud"
@@ -8,4 +11,6 @@ object AppConst {
     const val APP_TAG = "Legado"
     const val RC_IMPORT_YUEDU_DATA = 100
 
+    val NOT_AVAILABLE = App.INSTANCE.getString(R.string.not_available)
+
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/data/AppDatabase.kt b/app/src/main/java/io/legado/app/data/AppDatabase.kt
index f5db6c908..4e3be84f6 100644
--- a/app/src/main/java/io/legado/app/data/AppDatabase.kt
+++ b/app/src/main/java/io/legado/app/data/AppDatabase.kt
@@ -21,8 +21,6 @@ abstract class AppDatabase : RoomDatabase() {
     companion object {
         private const val DATABASE_NAME = "legado.db"
 
-
-
         private val MIGRATION_1_2: Migration = object : Migration(1, 2) {
             override fun migrate(database: SupportSQLiteDatabase) {
                 database.run {
diff --git a/app/src/main/java/io/legado/app/data/dao/BookDao.kt b/app/src/main/java/io/legado/app/data/dao/BookDao.kt
index 6e71ae680..aae85f47f 100644
--- a/app/src/main/java/io/legado/app/data/dao/BookDao.kt
+++ b/app/src/main/java/io/legado/app/data/dao/BookDao.kt
@@ -16,4 +16,7 @@ interface BookDao {
     @Query("SELECT descUrl FROM books WHERE `group` = :group")
     fun observeUrlsByGroup(group: Int): LiveData<List<String>>
 
+    @Query("SELECT * FROM books WHERE `name` in (:names)")
+    fun findByName(vararg names: String): List<Book>
+
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/data/entities/Book.kt b/app/src/main/java/io/legado/app/data/entities/Book.kt
index fc601f9fe..1efd170c3 100644
--- a/app/src/main/java/io/legado/app/data/entities/Book.kt
+++ b/app/src/main/java/io/legado/app/data/entities/Book.kt
@@ -2,6 +2,7 @@ package io.legado.app.data.entities
 
 import android.os.Parcelable
 import androidx.room.*
+import io.legado.app.constant.AppConst.NOT_AVAILABLE
 import io.legado.app.utils.strim
 import kotlinx.android.parcel.Parcelize
 
@@ -11,7 +12,7 @@ data class Book(@PrimaryKey
                 var descUrl: String = "",                   // 详情页Url(本地书源存储完整文件路径)
                 var tocUrl: String = "",                    // 目录页Url (toc=table of Contents)
                 var sourceId: Int = -1,                     // 书源规则id(默认-1,表示本地书籍)
-                var name: String = "",                      // 书籍名称(书源获取)
+                var name: String? = null,                      // 书籍名称(书源获取)
                 var customName: String? = null,                // 书籍名称(用户修改)
                 var author: String? = null,                 // 作者名称(书源获取)
                 var customAuthor: String? = null,           // 作者名称(用户修改)
@@ -39,12 +40,12 @@ data class Book(@PrimaryKey
 
     fun getUnreadChapterNum() = Math.max(totalChapterNum - durChapterIndex - 1, 0)
 
-    fun getDisplayName() = customName.strim() ?: name
+    fun getDisplayName() = customName ?: name ?: NOT_AVAILABLE
 
-    fun getDisplayAuthor() = customAuthor.strim() ?: author
+    fun getDisplayAuthor() = customAuthor ?: author ?: NOT_AVAILABLE
 
-    fun getDisplayCover() = customCoverUrl.strim() ?: coverUrl
+    fun getDisplayCover() = customCoverUrl ?: coverUrl
 
-    fun getDisplayDescription() = customDescription.strim() ?: description
+    fun getDisplayDescription() = customDescription ?: description
 
 }
\ No newline at end of file
diff --git a/app/src/main/java/io/legado/app/data/entities/rule/Rule.kt b/app/src/main/java/io/legado/app/data/entities/rule/Rule.kt
index ad2d16509..7b3810802 100644
--- a/app/src/main/java/io/legado/app/data/entities/rule/Rule.kt
+++ b/app/src/main/java/io/legado/app/data/entities/rule/Rule.kt
@@ -18,11 +18,26 @@ data class Rule (
             input.startsWith("$.") -> parseJSON(input)
             input.startsWith("//") -> parseXPATH(input)
             input.startsWith("RE:") -> parseREGEX(input)
-            input.contains("{{") && input.contains("}}") -> parseJS(input)
-            input.contains("{") && input.contains("}") -> parseCONST(input)
+            isJsRule(input) -> parseJS(input)
+            isConstRule(input) -> parseCONST(input)
             else -> parseCSS(input)
         }
 
+        private fun isJsRule(input: String): Boolean {
+            val open = input.indexOf("{{")
+            if (open < 0) return false
+            val close = input.indexOf("}}", open)
+            return close > 0
+        }
+
+        private fun isConstRule(input: String): Boolean {
+            val open = input.indexOf("{")
+            if (open < 0) return false
+            val close = input.indexOf("}", open)
+            return close > 0
+        }
+
+
         private fun parseCSS(rawRule: String): List<BaseRule> {
             val rules = mutableListOf<BaseRule>()
             for (line in rawRule.splitNotBlank("\n")) {
@@ -60,10 +75,6 @@ data class Rule (
             return rules
         }
 
-        private fun parseREGEX(rawRule: String): List<BaseRule> {
-            TODO()
-        }
-
         private fun parseCONST(rawRule: String): List<BaseRule> {
             val rules = mutableListOf<BaseRule>()
             val subRule = mutableListOf<String>()
@@ -85,6 +96,10 @@ data class Rule (
             TODO()
         }
 
+        private fun parseREGEX(rawRule: String): List<BaseRule> {
+            TODO()
+        }
+
     }
 }