diff --git a/aos/build/java.gypi b/aos/build/java.gypi
new file mode 100644
index 0000000..d832b0a
--- /dev/null
+++ b/aos/build/java.gypi
@@ -0,0 +1,74 @@
+# Include this file in any target that is going to build java files.
+#
+# To use, create a target of the following form:
+# {
+#   'target_name': 'whatever',
+#   'variables': {
+#     'srcdirs': ['.', 'java'],
+#   },
+#   'includes': ['path/to/java.gypi'],
+# }
+# See below for more variables.
+# To make any output jars include some loadable modules, set the 'jni_libs'
+#   variable in 'direct_dependent_settings'. Making this easier causes lots of
+#   recursion issues in gyp.
+#   The dependency on these targets also has to be added manually.
+{
+  'type': 'none',
+  'variables': {
+# The manifest file for creating the jar.
+    'manifest%': '/dev/null',
+# Additional jars/directories to add to the classpath when compiling.
+# This target will automatically add itself to this list for any dependents.
+    'classpath': [],
+# Classes to generate JNI headers for.
+# They will be able to be #included as "jni/package_ClassName.h" by targets
+#   that depend on this one.
+    'gen_headers': [],
+# Like 'srcdirs', except not required to exist at gyp time. However, nothing
+#   here will depend on any files in these directories.
+    'gen_srcdirs': ['/dev/null'],
+# Like 'gen_srcdirs', except all folders that are children of this folder will
+#   be used instead.
+    'gen_srcdir_parents%': [],
+    'srcdirs': ['/dev/null'],
+    'jar_dir': '<(PRODUCT_DIR)/jars',
+    'java_files': '<!(find <(srcdirs) -name *.java)',
+    'create_jar': '<(AOS)/build/create_jar',
+    'out_jar': '<(jar_dir)/<(_target_name).jar',
+    'header_dir': '<(SHARED_INTERMEDIATE_DIR)/jni_headers_<!(pwd | sed s:/:_:g)_<(_target_name)',
+    'no_rsync': 1,
+  },
+  'direct_dependent_settings': {
+    'variables': {
+      'classpath': ['<(out_jar)'],
+    },
+    'include_dirs': [
+      '<(header_dir)',
+    ],
+  },
+  'actions': [
+    {
+      'action_name': 'run javac',
+      'message': 'Compiling java code',
+      'inputs': [
+        '<(create_jar)',
+        '<@(java_files)',
+        '>@(classpath)',
+        '>@(gen_srcdirs)',
+        '>(manifest)',
+      ],
+      'outputs': [
+        '<(out_jar)',
+      ],
+      'action': [
+        '<(create_jar)',
+        '<(srcdirs) <(gen_srcdirs)',
+        '<(INTERMEDIATE_DIR)', '>(classpath)',
+        '>(gen_srcdir_parents)',
+        '>(manifest)', '<(out_jar)',
+        '<(header_dir)/jni', '>(gen_headers)',
+      ],
+    },
+  ],
+}