diff --git a/openjdk-7-jre/Dockerfile b/openjdk-7-jre/Dockerfile
index 10be788..9ef805f 100644
--- a/openjdk-7-jre/Dockerfile
+++ b/openjdk-7-jre/Dockerfile
@@ -9,10 +9,9 @@
 FROM dockerfile/ubuntu
 
 # Install Java.
-RUN \
-  apt-get update && \
-  apt-get install -y openjdk-7-jre && \
-  rm -rf /var/lib/apt/lists/*
+RUN apt-get update
+RUN DEBIAN_FRONTEND='noninteractive' apt-get -y -o Dpkg::Options::='--force-confdef' -o Dpkg::Options::='--force-confold' install -y openjdk-7-jre
+RUN rm -rf /var/lib/apt/lists/*
 
 # Define working directory.
 WORKDIR /data