diff --git a/build.py b/build.py
index 6d540926ce26a788efef4bcac5c36834d2568bd9..769e9c3a7bec26040cba468794ff4438adef186c 100755
--- a/build.py
+++ b/build.py
@@ -22,62 +22,69 @@ import sys
 import argparse
 import subprocess
 import re
+import threading
+
+lock = threading.Lock()
 
 
 def main():
-    parser = argparse.ArgumentParser()
-    parser.add_argument('--haptobin', required=True)
-    parser.add_argument('--haptobinOutput', required=True)
-    parser.add_argument('--unpackOutput', required=True)
-    parser.add_argument('--packOutput', required=True)
-    parser.add_argument('--outpath', required=True)
-    args = parser.parse_args()
-    print(args.haptobinOutput)
-    print(args.unpackOutput)
-    print(args.packOutput)
-    print(args.outpath)
-    root_dir = os.path.dirname(os.path.realpath(__file__))
-    time_out = 5000
+    try:
+        lock.acquire()
+        parser = argparse.ArgumentParser()
+        parser.add_argument('--haptobin', required=True)
+        parser.add_argument('--haptobinOutput', required=True)
+        parser.add_argument('--unpackOutput', required=True)
+        parser.add_argument('--packOutput', required=True)
+        parser.add_argument('--outpath', required=True)
+        args = parser.parse_args()
+        print(args.haptobinOutput)
+        print(args.unpackOutput)
+        print(args.packOutput)
+        print(args.outpath)
+        root_dir = os.path.dirname(os.path.realpath(__file__))
+        time_out = 5000
 
-    # compile haptobin_tool.jar
-    hap_to_bin_shell_path = os.path.join(root_dir, "haptobin.sh")
-    command_haptobin = ['bash', hap_to_bin_shell_path, root_dir, args.haptobinOutput, args.outpath]
-    child_haptobin = subprocess.Popen(command_haptobin, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-    haptobin_out, haptobin_err = child_haptobin.communicate(timeout=time_out)
-    if child_haptobin.returncode != 0:
-        print(haptobin_out.decode('utf-8'))
-        print(haptobin_err.decode('utf-8'))
-        raise Exception("compile haptobin java class failed!")
+        # compile haptobin_tool.jar
+        hap_to_bin_shell_path = os.path.join(root_dir, "haptobin.sh")
+        command_haptobin = ['bash', hap_to_bin_shell_path, root_dir, args.haptobinOutput, args.outpath]
+        child_haptobin = subprocess.Popen(command_haptobin, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        haptobin_out, haptobin_err = child_haptobin.communicate(timeout=time_out)
+        if child_haptobin.returncode != 0:
+            print(haptobin_out.decode('utf-8'))
+            print(haptobin_err.decode('utf-8'))
+            raise Exception("compile haptobin java class failed!")
 
-    # compile app_unpacking_tool.jar
-    version = subprocess.check_output(['javac', '-version'], stderr=subprocess.STDOUT)
-    version = version.decode('utf-8')
-    array = re.findall(r'\d+', version)
-    compatible_version = 8
-    big_version = ''
-    if int(array[0]) > compatible_version:
-        big_version = 'true'
-    else:
-        big_version = 'false'
-    
-    unpack_tool_shell_path = os.path.join(root_dir, "unpackingTool.sh")
-    command_unpack = ['bash', unpack_tool_shell_path, root_dir, args.unpackOutput, args.outpath, big_version]
-    child_unpack = subprocess.Popen(command_unpack, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-    unpack_out, unpack_err = child_unpack.communicate(timeout=time_out)
-    if child_unpack.returncode != 0:
-        print(unpack_out.decode('utf-8'))
-        print(unpack_err.decode('utf-8'))
-        raise Exception("compile unapcking tool java class failed!")
-    
-    #compile app_packing_tool.jar
-    pack_tool_shell_path = os.path.join(root_dir, "packingTool.sh")
-    command_pack = ['bash', pack_tool_shell_path, root_dir, args.packOutput, args.outpath]
-    child_pack = subprocess.Popen(command_pack, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
-    pack_out, pack_err = child_pack.communicate(timeout=time_out)
-    if child_pack.returncode != 0:
-        print(pack_out.decode('utf-8'))
-        print(pack_err.decode('utf-8'))
-        raise Exception("compile packing tool java class failed!")
+        # compile app_unpacking_tool.jar
+        version = subprocess.check_output(['javac', '-version'], stderr=subprocess.STDOUT)
+        version = version.decode('utf-8')
+        array = re.findall(r'\d+', version)
+        compatible_version = 8
+        big_version = ''
+        if int(array[0]) > compatible_version:
+            big_version = 'true'
+        else:
+            big_version = 'false'
+        
+        unpack_tool_shell_path = os.path.join(root_dir, "unpackingTool.sh")
+        command_unpack = ['bash', unpack_tool_shell_path, root_dir, args.unpackOutput, args.outpath, big_version]
+        child_unpack = subprocess.Popen(command_unpack, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        unpack_out, unpack_err = child_unpack.communicate(timeout=time_out)
+        if child_unpack.returncode != 0:
+            print(unpack_out.decode('utf-8'))
+            print(unpack_err.decode('utf-8'))
+            raise Exception("compile unapcking tool java class failed!")
+        
+        #compile app_packing_tool.jar
+        pack_tool_shell_path = os.path.join(root_dir, "packingTool.sh")
+        command_pack = ['bash', pack_tool_shell_path, root_dir, args.packOutput, args.outpath]
+        child_pack = subprocess.Popen(command_pack, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+        pack_out, pack_err = child_pack.communicate(timeout=time_out)
+        if child_pack.returncode != 0:
+            print(pack_out.decode('utf-8'))
+            print(pack_err.decode('utf-8'))
+            raise Exception("compile packing tool java class failed!")
+    finally:
+        lock.release()
 
 if __name__ == '__main__':
     sys.exit(main())