diff --git a/java/java.go b/java/java.go
index ca99e69..a48ac0a 100644
--- a/java/java.go
+++ b/java/java.go
@@ -587,6 +587,7 @@
 	JAVA_VERSION_9           = 9
 	JAVA_VERSION_11          = 11
 	JAVA_VERSION_17          = 17
+	JAVA_VERSION_21          = 21
 )
 
 func (v javaVersion) String() string {
@@ -605,6 +606,8 @@
 		return "11"
 	case JAVA_VERSION_17:
 		return "17"
+	case JAVA_VERSION_21:
+		return "21"
 	default:
 		return "unsupported"
 	}
@@ -647,6 +650,8 @@
 		return JAVA_VERSION_11
 	case "17":
 		return JAVA_VERSION_17
+	case "21":
+		return JAVA_VERSION_21
 	case "10", "12", "13", "14", "15", "16":
 		ctx.PropertyErrorf("java_version", "Java language level %s is not supported", javaVersion)
 		return JAVA_VERSION_UNSUPPORTED