diff --git a/README.md b/README.md
index 30da8fb..3f53a9f 100644
--- a/README.md
+++ b/README.md
@@ -7,7 +7,7 @@ This is an implementation of Tron eventsubscribe model.
 * **kafkaplugin** module is the implementation for kafka, it implements IPluginEventListener, it receives events subscribed from Java-tron and relay events to kafka server. 
 * **mongodbplugin** mongodbplugin module is the implementation for mongodb. 
 ### Setup/Build
-
+Eventplugin can be built with JDK 8 or JDK17.
 1. Clone the repo
 2. Go to eventplugin `cd eventplugin` 
 3. run `./gradlew build`
@@ -20,7 +20,11 @@ This is an implementation of Tron eventsubscribe model.
 event.subscribe = {
     path = "" // absolute path of plugin
     server = "" // target server address to receive event triggers
-    dbconfig = "" // dbname|username|password, if you want to create indexes for collections when the collections are not exist, you can add version and set it to 2, as dbname|username|password|version
+    # dbname|username|password, if you want to create indexes for collections when the collections
+    # are not exist, you can add version and set it to 2, as dbname|username|password|version
+    # if you use version 2 and one collection not exists, it will create index automaticaly;
+    # if you use version 2 and one collection exists, it will not create index, you must create index manually;
+    dbconfig = ""
     topics = [
         {
           triggerName = "block" // block trigger, the value can't be modified
diff --git a/build.gradle b/build.gradle
index edf5ae0..c26b5fb 100644
--- a/build.gradle
+++ b/build.gradle
@@ -8,13 +8,13 @@ subprojects {
 
   dependencies {
     compileOnly group: 'org.apache.commons', name: 'commons-lang3', version: '3.5'
-    compileOnly 'org.projectlombok:lombok:1.18.12'
+    compileOnly 'org.projectlombok:lombok:1.18.34'
     compileOnly group: 'org.pf4j', name: 'pf4j', version: "${pf4jVersion}"
     compileOnly group: 'ch.qos.logback', name: 'logback-classic', version: '1.2.13'
-    annotationProcessor 'org.projectlombok:lombok:1.18.12'
+    annotationProcessor 'org.projectlombok:lombok:1.18.34'
     annotationProcessor group: 'org.pf4j', name: 'pf4j', version: "${pf4jVersion}"
-    testCompileOnly 'org.projectlombok:lombok:1.18.12'
-    testAnnotationProcessor 'org.projectlombok:lombok:1.18.12'
+    testCompileOnly 'org.projectlombok:lombok:1.18.34'
+    testAnnotationProcessor 'org.projectlombok:lombok:1.18.34'
     testAnnotationProcessor group: 'org.pf4j', name: 'pf4j', version: "${pf4jVersion}"
     compileOnly group: 'org.slf4j', name: 'slf4j-api', version: '1.7.25'
     compileOnly group: 'org.slf4j', name: 'jcl-over-slf4j', version: '1.7.25'
diff --git a/plugins/mongodbplugin/src/main/java/org/tron/mongodb/util/Pager.java b/plugins/mongodbplugin/src/main/java/org/tron/mongodb/util/Pager.java
index c2172b1..5ef28df 100644
--- a/plugins/mongodbplugin/src/main/java/org/tron/mongodb/util/Pager.java
+++ b/plugins/mongodbplugin/src/main/java/org/tron/mongodb/util/Pager.java
@@ -38,8 +38,8 @@ public static void handle(HashMap<String, Integer> hs, int currentPage, int page
 		int start = (currentPage - 1) * pageSize;
 		int offset = pageSize;
 
-		hs.put("start", new Integer(start));
-		hs.put("offset", new Integer(offset));
+		hs.put("start", start);
+		hs.put("offset", offset);
 	}
 
 	public Pager() {