Update versions.

build.gradle

@@ -1,13 +1,13 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.4.21'
+    ext.kotlin_version = '1.5.21'
     repositories {
         google()
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:4.1.2'
+        classpath 'com.android.tools.build:gradle:7.0.1'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
     }
 }

core/build.gradle

@@ -2,13 +2,11 @@ apply plugin: 'com.android.library'
 apply plugin: 'kotlin-android'
 
 android {
-    compileSdkVersion 30
+    compileSdkVersion 31
 
     defaultConfig {
         minSdkVersion 15
-        targetSdkVersion 30
-        versionCode 1
-        versionName "1.0"
+        targetSdkVersion 31
         archivesBaseName = "core"
     }
     buildTypes {
@@ -20,36 +18,13 @@ android {
     lintOptions {
         abortOnError false
     }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
 }
 
 dependencies {
     api fileTree(dir: 'libs', include: ['*.jar'])
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
-}
-
-apply plugin: 'com.github.panpf.bintray-publish'
-
-allprojects {
-    tasks.withType(Javadoc) {
-        options.addStringOption('Xdoclint:none', '-quiet')
-        options.addStringOption('encoding', 'UTF-8')
-    }
-}
-
-buildscript {
-    repositories {
-        jcenter()
-    }
-    dependencies {
-        classpath 'com.github.panpf.bintray-publish:bintray-publish:1.0.0'
-    }
-}
-
-publish {
-    userOrg = 'sinyu890807'
-    groupId = 'org.litepal.guolindev'
-    artifactId = 'core'
-    publishVersion = '3.2.3'
-    desc = 'An Android library that allows developers to use SQLite database extremely easy'
-    website = 'https://github.com/LitePalFramework/LitePal'
 }

gradle/wrapper/gradle-wrapper.properties

@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.0.2-bin.zip

sample/build.gradle

@@ -2,12 +2,12 @@ apply plugin: 'com.android.application'
 apply plugin: 'kotlin-android'
 
 android {
-    compileSdkVersion 30
+    compileSdkVersion 31
 
     defaultConfig {
         applicationId "org.litepal.litepalsample"
         minSdkVersion 15
-        targetSdkVersion 30
+        targetSdkVersion 31
         versionCode 1
         versionName "1.0"
         testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
@@ -21,6 +21,10 @@ android {
     lintOptions {
         abortOnError false
     }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
 }
 
 dependencies {