Default import of java.time.*

src/main/groovy/org/grails/gradle/plugin/core/GrailsExtension.groovy

@@ -43,6 +43,11 @@ class GrailsExtension {
      */
     boolean pathingJar = false
 
+    /**
+     * Whether java.time.* package should be a default import package
+     */
+    boolean javaTime = true
+
     /**
      * Configure the reloading agent
      */

src/main/groovy/org/grails/gradle/plugin/core/GrailsGradlePlugin.groovy

@@ -289,6 +289,28 @@ class GrailsGradlePlugin extends GroovyPlugin {
                 }
             }
         }
+
+        GrailsExtension grailsExt = project.extensions.getByType(GrailsExtension)
+        project.tasks.withType(GroovyCompile).configureEach { groovyCompileTask ->
+            if (grailsExt.javaTime) {
+                groovyCompileTask.doFirst {
+                    def configScriptStream = getClass().getResourceAsStream("/GrailsCompilerConfig.groovy")
+                    if (configScriptStream != null) {
+                        def tempConfigScriptFile = File.createTempFile("build/GrailsCompilerConfig", ".groovy")
+                        tempConfigScriptFile.mkdirs()
+                        tempConfigScriptFile.deleteOnExit()
+
+                        def existingScript = groovyCompileTask.groovyOptions.configurationScript
+                        if (existingScript) {
+                            tempConfigScriptFile << existingScript.text
+                        }
+
+                        tempConfigScriptFile.text = configScriptStream.text
+                        groovyCompileTask.groovyOptions.configurationScript = tempConfigScriptFile
+                    }
+                }
+            }
+        }
     }
 
     @CompileStatic

src/main/groovy/org/grails/gradle/plugin/web/gsp/GroovyPagePlugin.groovy

@@ -80,7 +80,6 @@ class GroovyPagePlugin implements Plugin<Project> {
             }
         }
 
-
         compileGroovyPages.dependsOn( allTasks.findByName("classes") )
         compileGroovyPages.dependsOn( compileWebappGroovyPages )
 

src/main/resources/GrailsCompilerConfig.groovy

@@ -0,0 +1,6 @@
+import org.codehaus.groovy.control.customizers.ImportCustomizer
+
+def importCustomizer = new ImportCustomizer()
+importCustomizer.addStarImports('java.time')
+
+configuration.addCompilationCustomizers(importCustomizer)