Fixed it so that 'java-base' instead of 'java' plugin is applied in the plugin. Applying 'java' is now a choice of the user

Author: ysb33r

README.md

@@ -31,14 +31,16 @@ apply plugin: 'com.github.jrubygradle.jar'
 
 This loads the following plugins if they are not already loaded:
 + `com.github.jrubygradle.base`
-+ `java`
++ `java-base`
 
 ## Using the plugin
 
 This plugin does not add any new tasks or extensions, extends the `Jar` task type with a `jruby` closure. If the `java` plugin
 is loaded, then the `jar` task can also be configured.
 
 ```groovy
+apply plugin: 'java'
+
 jar {
   jruby {
   
@@ -105,7 +107,7 @@ buildscript {
 
 apply plugin: 'com.github.jrubygradle.jar'
 apply plugin: 'com.github.johnrengelman.shadow'
-
+apply plugin: 'java'
 ```
 
 ### Configuring Shadow JAR

src/main/groovy/com/github/jrubygradle/jar/JRubyJarPlugin.groovy

@@ -20,7 +20,7 @@ class JRubyJarPlugin implements Plugin<Project> {
     void apply(Project project) {
 
         project.apply plugin : 'com.github.jruby-gradle.base'
-        project.apply plugin : 'java'
+        project.apply plugin : 'java-base'
         project.configurations.maybeCreate('jrubyEmbeds')
         project.configurations.maybeCreate('jrubyJar')
 
@@ -57,12 +57,15 @@ class JRubyJarPlugin implements Plugin<Project> {
 
         }
 
-        project.sourceSets {
-            main {
-                java {
-                    srcDir new File(project.buildDir,'generated/java')
-                }
-            }
+//        project.sourceSets {
+//            main {
+//                java {
+//                    srcDir new File(project.buildDir,'generated/java')
+//                }
+//            }
+//        }
+        project.sourceSets.matching { it.name == "main" } .all {
+            it.java.srcDir new File(project.buildDir,'generated/java')
         }
     }
     @PackageScope