diff --git a/Bliss OS/build-guide/index.html b/Bliss OS/build-guide/index.html
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+++ b/Bliss OS/build-guide/index.html
@@ -860,6 +860,7 @@
 <p>Install OpenJDK:</p>
 <pre><code>sudo apt install openjdk-8-jdk
 </code></pre>
+<p>From the AOSP 9.0, the AOSP uses the prebuilt JDK in code repository, so it is not required if building system based on AOSP 9.0 and above version.</p>
 <h2 id="install-build-tools">Install build tools</h2>
 <p>To install the required build tools, run the following command:</p>
 <pre><code>sudo apt-get install git-core gnupg flex bison maven gperf build-essential zip curl zlib1g-dev gcc-multilib g++-multilib libc6-dev-i386  lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z-dev ccache libgl1-mesa-dev libxml2-utils xsltproc unzip squashfs-tools python-mako libssl-dev ninja-build lunzip syslinux syslinux-utils gettext genisoimage gettext bc xorriso libncurses5