updated gradle

use dokka instead of javadoc

build.gradle

@@ -1,7 +1,7 @@
 // Top-level build file where you can add configuration options common to all sub-projects/modules.
 
 buildscript {
-    ext.kotlin_version = '1.3.20'
+    ext.kotlin_version = '1.3.21'
 
     ext {
         group = 'com.github.markusressel'
@@ -44,6 +44,7 @@ buildscript {
         classpath "com.android.tools.build:gradle:$gradle_plugin_version"
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath 'com.github.dcendents:android-maven-gradle-plugin:2.1'
+        classpath "org.jetbrains.dokka:dokka-android-gradle-plugin:0.9.17"
     }
 }
 

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-4.10.2-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.2.1-all.zip

library/build.gradle

@@ -1,5 +1,6 @@
 apply plugin: 'com.android.library'
 apply plugin: 'kotlin-android'
+apply plugin: 'org.jetbrains.dokka-android'
 
 apply plugin: 'com.github.dcendents.android-maven'
 group = rootProject.ext.group
@@ -69,20 +70,12 @@ task sourcesJar(type: Jar) {
     classifier = 'sources'
 }
 
-task javadoc(type: Javadoc) {
-    failOnError false
-    source = android.sourceSets.main.java.sourceFiles
-    classpath += project.files(android.getBootClasspath().join(File.pathSeparator))
-    classpath += configurations.compile
-}
-
-// build a jar with javadoc
-task javadocJar(type: Jar, dependsOn: javadoc) {
+task dokkaJar(type: Jar, dependsOn: dokka) {
     classifier = 'javadoc'
-    from javadoc.destinationDir
+    from dokka.outputDirectory
 }
 
 artifacts {
     archives sourcesJar
-    archives javadocJar
+    archives dokkaJar
 }