diff --git a/third_party/jarjar/BUILD b/third_party/jarjar/BUILD
index 4f4f223b08859c..bc3d075fd9f246 100644
--- a/third_party/jarjar/BUILD
+++ b/third_party/jarjar/BUILD
@@ -16,6 +16,7 @@ filegroup(
     ],
 )
 
+# jarjar_bin
 java_binary(
     name = "jarjar_command",
     srcs = glob(
diff --git a/third_party/java/java_tools/README.md b/third_party/java/java_tools/README.md
index 82bd2fb18962a2..408669c11285fc 100644
--- a/third_party/java/java_tools/README.md
+++ b/third_party/java/java_tools/README.md
@@ -17,3 +17,8 @@ third_party/java/java_tools/JacocoCoverage_jarjar_deploy.jar
 third_party/java/java_tools/turbine_deploy.jar
 third_party/java/java_tools/turbine_direct_binary_deploy.jar
 third_party/java/java_tools/SingleJar_deploy.jar
+
+The following tools were built with bazel 0.21.0 at commit 019f13b64630ea7e7837a2ed8b664c4262322b1c by running:
+$ third_party/java/java_tools/update_java_tools.sh
+
+third_party/java/java_tools/jarjar_command_deploy.jar
\ No newline at end of file
diff --git a/third_party/java/java_tools/jarjar_command_deploy.jar b/third_party/java/java_tools/jarjar_command_deploy.jar
new file mode 100755
index 00000000000000..10bae8897c867c
Binary files /dev/null and b/third_party/java/java_tools/jarjar_command_deploy.jar differ
diff --git a/third_party/java/java_tools/update_java_tools.sh b/third_party/java/java_tools/update_java_tools.sh
index 1c44b217794953..c77013c3c2855f 100755
--- a/third_party/java/java_tools/update_java_tools.sh
+++ b/third_party/java/java_tools/update_java_tools.sh
@@ -15,7 +15,8 @@ declare -A tool_name_to_target=(["JavaBuilder"]="src/java_tools/buildjar:JavaBui
 ["JacocoCoverage"]="src/java_tools/junitrunner/java/com/google/testing/coverage:JacocoCoverage_jarjar_deploy.jar" \
 ["Turbine"]="src/java_tools/buildjar/java/com/google/devtools/build/java/turbine/javac:turbine_deploy.jar" \
 ["TurbineDirect"]="src/java_tools/buildjar/java/com/google/devtools/build/java/turbine:turbine_direct_binary_deploy.jar" \
-["SingleJar"]="src/java_tools/singlejar/java/com/google/devtools/build/singlejar:bazel-singlejar_deploy.jar")
+["SingleJar"]="src/java_tools/singlejar/java/com/google/devtools/build/singlejar:bazel-singlejar_deploy.jar"
+["JarJar"]="third_party/jarjar:jarjar_command_deploy.jar")
 
 usage="This script updates the checked-in jars corresponding to the tools "\
 "used by the Java rules in Bazel.