diff --git a/java/config/config.go b/java/config/config.go
index 2f0240c..3159a05 100644
--- a/java/config/config.go
+++ b/java/config/config.go
@@ -132,12 +132,7 @@
 		if override := ctx.Config().Getenv("OVERRIDE_JLINK_VERSION_NUMBER"); override != "" {
 			return override
 		}
-		switch ctx.Config().Getenv("EXPERIMENTAL_USE_OPENJDK21_TOOLCHAIN") {
-		case "true":
-			return "21"
-		default:
-			return "17"
-		}
+		return "21"
 	})
 
 	pctx.SourcePathVariable("JavaToolchain", "${JavaHome}/bin")
diff --git a/ui/build/config.go b/ui/build/config.go
index 1a25397..3143b6b 100644
--- a/ui/build/config.go
+++ b/ui/build/config.go
@@ -386,22 +386,21 @@
 
 	// Configure Java-related variables, including adding it to $PATH
 	java8Home := filepath.Join("prebuilts/jdk/jdk8", ret.HostPrebuiltTag())
-	java17Home := filepath.Join("prebuilts/jdk/jdk17", ret.HostPrebuiltTag())
 	java21Home := filepath.Join("prebuilts/jdk/jdk21", ret.HostPrebuiltTag())
 	javaHome := func() string {
 		if override, ok := ret.environ.Get("OVERRIDE_ANDROID_JAVA_HOME"); ok {
 			return override
 		}
-		if ret.environ.IsEnvTrue("EXPERIMENTAL_USE_OPENJDK21_TOOLCHAIN") {
-			return java21Home
-		}
 		if toolchain11, ok := ret.environ.Get("EXPERIMENTAL_USE_OPENJDK11_TOOLCHAIN"); ok && toolchain11 != "true" {
-			ctx.Fatalln("The environment variable EXPERIMENTAL_USE_OPENJDK11_TOOLCHAIN is no longer supported. An OpenJDK 11 toolchain is now the global default.")
+			ctx.Fatalln("The environment variable EXPERIMENTAL_USE_OPENJDK11_TOOLCHAIN is no longer supported. An OpenJDK 21 toolchain is now the global default.")
 		}
 		if toolchain17, ok := ret.environ.Get("EXPERIMENTAL_USE_OPENJDK17_TOOLCHAIN"); ok && toolchain17 != "true" {
-			ctx.Fatalln("The environment variable EXPERIMENTAL_USE_OPENJDK17_TOOLCHAIN is no longer supported. An OpenJDK 17 toolchain is now the global default.")
+			ctx.Fatalln("The environment variable EXPERIMENTAL_USE_OPENJDK17_TOOLCHAIN is no longer supported. An OpenJDK 21 toolchain is now the global default.")
 		}
-		return java17Home
+		if toolchain21, ok := ret.environ.Get("EXPERIMENTAL_USE_OPENJDK21_TOOLCHAIN"); ok && toolchain21 != "true" {
+			ctx.Fatalln("The environment variable EXPERIMENTAL_USE_OPENJDK21_TOOLCHAIN is no longer supported. An OpenJDK 21 toolchain is now the global default.")
+		}
+		return java21Home
 	}()
 	absJavaHome := absPath(ctx, javaHome)