close this pr

CONTRIBUTING.md

@@ -36,6 +36,8 @@ Before submitting the code, we need to do some preparation:
    git config user.email "{email-address-of-github}" # like "jermy@apache.org"
    ```
 
+5. Sign the HugeGraph CLA: [https://cla-assistant.io/hugegraph/hugegraph](https://cla-assistant.io/hugegraph/hugegraph)
+
 Optional: You can use [GitHub desktop](https://desktop.github.com/) to greatly simplify the commit and update process.
 
 ## 2. Create an Issue on GitHub
@@ -108,13 +110,6 @@ Note that since GitHub requires submitting code through `username + token` (inst
 
 Go to the web page of GitHub fork repo, there would be a chance to create a Pull Request after pushing to a new branch, just click button "Compare & pull request" to do it. Then edit the description for proposed changes, which can just be copied from the commit message.
 
-Please sign the HugeGraph CLA when contributing code for the first time. You can sign the CLA by just posting a Pull Request Comment same as the below format:
-
-`I have read the CLA Document and I hereby sign the CLA`
-
-Note: please make sure the email address you used to submit the code is bound to the GitHub account. For how to bind the email address, please refer to https://github.com/settings/emails:
-<img width="1280" alt="image" src="https://user-images.githubusercontent.com/9625821/163522445-2a50a72a-dea2-434f-9868-3a0d40d0d037.png">
-
 ## 5. Code review
 
  Maintainers will start the code review after all the **automatic** checks are passed:

hugegraph-core/src/main/java/com/baidu/hugegraph/HugeFactory.java

@@ -44,7 +44,7 @@ public class HugeFactory {
 
     private static final Logger LOG = Log.logger(HugeGraph.class);
 
-    private static final Thread shutdownHook = new Thread(() -> {
+    private static final Thread SHUTDOWN_HOOK = new Thread(() -> {
         LOG.info("HugeGraph is shutting down");
         HugeFactory.shutdown(30L);
     }, "hugegraph-shutdown");
@@ -53,14 +53,14 @@ public class HugeFactory {
         SerialEnum.registerInternalEnums();
         HugeGraph.registerTraversalStrategies(StandardHugeGraph.class);
 
-        Runtime.getRuntime().addShutdownHook(shutdownHook);
+        Runtime.getRuntime().addShutdownHook(SHUTDOWN_HOOK);
     }
 
     private static final String NAME_REGEX = "^[A-Za-z][A-Za-z0-9_]{0,47}$";
 
-    private static final Map<String, HugeGraph> graphs = new HashMap<>();
+    private static final Map<String, HugeGraph> GRAPHS = new HashMap<>();
 
-    private static final AtomicBoolean shutdown = new AtomicBoolean(false);
+    private static final AtomicBoolean SHUTDOWN = new AtomicBoolean(false);
 
     public static synchronized HugeGraph open(Configuration config) {
         HugeConfig conf = config instanceof HugeConfig ?
@@ -82,10 +82,10 @@ public static synchronized HugeGraph open(HugeConfig config) {
         String name = config.get(CoreOptions.STORE);
         checkGraphName(name, "graph config(like hugegraph.properties)");
         name = name.toLowerCase();
-        HugeGraph graph = graphs.get(name);
+        HugeGraph graph = GRAPHS.get(name);
         if (graph == null || graph.closed()) {
             graph = new StandardHugeGraph(config);
-            graphs.put(name, graph);
+            GRAPHS.put(name, graph);
         } else {
             String backend = config.get(CoreOptions.BACKEND);
             E.checkState(backend.equalsIgnoreCase(graph.backend()),
@@ -105,7 +105,7 @@ public static HugeGraph open(URL url) {
 
     public static void remove(HugeGraph graph) {
         String name = graph.option(CoreOptions.STORE);
-        graphs.remove(name);
+        GRAPHS.remove(name);
     }
 
     public static void checkGraphName(String name, String configFile) {
@@ -143,7 +143,7 @@ public static PropertiesConfiguration getRemoteConfig(URL url) {
      * @param timeout seconds
      */
     public static void shutdown(long timeout) {
-        if (!shutdown.compareAndSet(false, true)) {
+        if (!SHUTDOWN.compareAndSet(false, true)) {
             return;
         }
         try {
@@ -154,14 +154,14 @@ public static void shutdown(long timeout) {
             OltpTraverser.destroy();
         } catch (Throwable e) {
             LOG.error("Error while shutdown", e);
-            shutdown.compareAndSet(true, false);
+            SHUTDOWN.compareAndSet(true, false);
             throw new HugeException("Failed to shutdown", e);
         }
 
         LOG.info("HugeFactory shutdown");
     }
 
     public static void removeShutdownHook() {
-        Runtime.getRuntime().removeShutdownHook(shutdownHook);
+        Runtime.getRuntime().removeShutdownHook(SHUTDOWN_HOOK);
     }
 }