diff --git a/Dockerfile b/Dockerfile
index 01475b0..22d04f4 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -43,6 +43,6 @@
 
 RUN DEBIAN_FRONTEND=noninteractive apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get -y install wget build-essential dh-make \
-                                              openjdk-19-jdk maven
-RUN update-java-alternatives --jre-headless --set /usr/lib/jvm/java-1.19.0-openjdk-amd64
+                                              openjdk-21-jdk maven
+RUN update-java-alternatives --jre-headless --set /usr/lib/jvm/java-1.21.0-openjdk-amd64
 
diff --git a/Makefile b/Makefile
index 683a624..8e25fa7 100644
--- a/Makefile
+++ b/Makefile
@@ -17,7 +17,7 @@
 # NOTE: pyang and pyangbind are required for build
 
 .PHONY: all clean package trees yang-ietf openapi_schemas yang2swagger
-JAVA := /usr/lib/jvm/java-19-openjdk-amd64/bin/java
+JAVA := /usr/lib/jvm/java-21-openjdk-amd64/bin/java
 PYANG := pyang
 ifeq ($(OS),Windows_NT)     # is Windows_NT on XP, 2000, 7, Vista, 10...
     PYTHON_INTERPRETER := python