Use JDK 17

Issue gh-611

buildSrc/build.gradle

@@ -5,7 +5,7 @@ plugins {
     id 'com.apollographql.apollo' version '2.4.5'
 }
 
-sourceCompatibility = JavaVersion.VERSION_11
+sourceCompatibility = JavaVersion.VERSION_17
 
 repositories {
     gradlePluginPortal()

buildSrc/src/main/groovy/io/spring/gradle/convention/SpringModulePlugin.groovy

@@ -14,8 +14,9 @@
  * the License.
  */
 
-package io.spring.gradle.convention;
+package io.spring.gradle.convention
 
+import org.gradle.api.JavaVersion;
 import org.gradle.api.Project
 import org.gradle.api.plugins.JavaLibraryPlugin;
 import org.gradle.api.plugins.MavenPlugin;
@@ -40,6 +41,7 @@ class SpringModulePlugin extends AbstractSpringJavaPlugin {
 		if (!Utils.isRelease(project)) {
 			deployArtifacts.dependsOn project.tasks.artifactoryPublish
 		}
+		project.java.sourceCompatibility = JavaVersion.VERSION_17
 	}
 
 }

gradle/java.gradle

@@ -1,6 +1,9 @@
 apply plugin: 'java'
 apply plugin: 'org.springframework.optional'
 
+sourceCompatibility = '17'
+targetCompatibility = '17'
+
 ext.apacheDsVersion = '1.5.5'
 ext.springVersion = '6.0.0-SNAPSHOT'
 ext.springDataVersion = '3.0.0-SNAPSHOT'