Use Error Prone 2.32.0

build.gradle

@@ -21,13 +21,15 @@ repositories {
   maven { url 'https://oss.sonatype.org/content/repositories/snapshots/' }
 }
 
-ext.errorproneVersion = '2.32.0'
+ext {
+  errorproneVersion = '2.32.0'
+  isJava17orHigher = JavaVersion.current() >= JavaVersion.VERSION_17
+  isJava21orHigher = JavaVersion.current() >= JavaVersion.VERSION_21
+}
 
 dependencies {
   implementation 'org.plumelib:options:2.0.3'
   implementation 'org.plumelib:plume-util:1.9.3'
-
-  compileOnly "com.google.errorprone:error_prone_annotations:${errorproneVersion}"
 }
 
 application {
@@ -66,7 +68,7 @@ spotless {
 // Error Prone linter
 
 dependencies {
-  errorprone('com.google.errorprone:error_prone_core:2.31.0')
+  errorprone("com.google.errorprone:error_prone_core:${errorproneVersion}")
 }
 tasks.withType(JavaCompile).configureEach {
   // "-processing" avoids javac warning "No processor claimed any of these annotations".
@@ -75,6 +77,7 @@ tasks.withType(JavaCompile).configureEach {
     disable('ExtendsObject')  // Incorrect when using the Checker Framework
     disable('ReferenceEquality') // Use Interning Checker instead.
   }
+  options.errorprone.enabled = isJava17orHigher
 }
 
 // Checker Framework pluggable type-checking