fix hugegraph-api code checkstyle

hugegraph-api/src/main/java/com/baidu/hugegraph/api/API.java

@@ -59,13 +59,13 @@ public class API {
     public static final String ACTION_ELIMINATE = "eliminate";
     public static final String ACTION_CLEAR = "clear";
 
-    private static final Meter succeedMeter =
+    private static final Meter SUCCEED_METER =
                          MetricsUtil.registerMeter(API.class, "commit-succeed");
-    private static final Meter illegalArgErrorMeter =
+    private static final Meter ILLEGAL_ARG_ERROR_METER =
                          MetricsUtil.registerMeter(API.class, "illegal-arg");
-    private static final Meter expectedErrorMeter =
+    private static final Meter EXPECTED_ERROR_METER =
                          MetricsUtil.registerMeter(API.class, "expected-error");
-    private static final Meter unknownErrorMeter =
+    private static final Meter UNKNOWN_ERROR_METER =
                          MetricsUtil.registerMeter(API.class, "unknown-error");
 
     public static HugeGraph graph(GraphManager manager, String graph) {
@@ -96,19 +96,19 @@ public static <R> R commit(HugeGraph g, Callable<R> callable) {
         try {
             R result = callable.call();
             g.tx().commit();
-            succeedMeter.mark();
+            SUCCEED_METER.mark();
             return result;
         } catch (IllegalArgumentException | NotFoundException |
                  ForbiddenException e) {
-            illegalArgErrorMeter.mark();
+            ILLEGAL_ARG_ERROR_METER.mark();
             rollback.accept(null);
             throw e;
         } catch (RuntimeException e) {
-            expectedErrorMeter.mark();
+            EXPECTED_ERROR_METER.mark();
             rollback.accept(e);
             throw e;
         } catch (Throwable e) {
-            unknownErrorMeter.mark();
+            UNKNOWN_ERROR_METER.mark();
             rollback.accept(e);
             // TODO: throw the origin exception 'e'
             throw new HugeException("Failed to commit", e);
@@ -171,7 +171,9 @@ protected static Map<String, Object> parseProperties(String properties) {
         Map<String, Object> props = null;
         try {
             props = JsonUtil.fromJson(properties, Map.class);
-        } catch (Exception ignored) {}
+        } catch (Exception ignored) {
+            // ignore
+        }
 
         // If properties is the string "null", props will be null
         E.checkArgument(props != null,

hugegraph-api/src/main/java/com/baidu/hugegraph/api/auth/ProjectAPI.java

@@ -176,6 +176,7 @@ public void delete(@Context GraphManager manager,
             throw new IllegalArgumentException("Invalid project id: " + id);
         }
     }
+
     public static boolean isAddGraph(String action) {
         return ACTION_ADD_GRAPH.equals(action);
     }
@@ -267,6 +268,6 @@ public void checkUpdate() {
                             this.description != null,
                             "Must specify 'graphs' or 'description' " +
                             "field that need to be updated");
-            }
         }
+    }
 }

hugegraph-api/src/main/java/com/baidu/hugegraph/api/graph/BatchAPI.java

@@ -47,11 +47,11 @@ public class BatchAPI extends API {
     private static final Logger LOG = Log.logger(BatchAPI.class);
 
     // NOTE: VertexAPI and EdgeAPI should share a counter
-    private static final AtomicInteger batchWriteThreads = new AtomicInteger(0);
+    private static final AtomicInteger BATCH_WRITE_THREADS = new AtomicInteger(0);
 
     static {
         MetricsUtil.registerGauge(RestServer.class, "batch-write-threads",
-                                  () -> batchWriteThreads.intValue());
+                                  () -> BATCH_WRITE_THREADS.intValue());
     }
 
     private final Meter batchMeter;
@@ -64,24 +64,24 @@ public BatchAPI() {
     public <R> R commit(HugeConfig config, HugeGraph g, int size,
                         Callable<R> callable) {
         int maxWriteThreads = config.get(ServerOptions.MAX_WRITE_THREADS);
-        int writingThreads = batchWriteThreads.incrementAndGet();
+        int writingThreads = BATCH_WRITE_THREADS.incrementAndGet();
         if (writingThreads > maxWriteThreads) {
-            batchWriteThreads.decrementAndGet();
+            BATCH_WRITE_THREADS.decrementAndGet();
             throw new HugeException("The rest server is too busy to write");
         }
 
-        LOG.debug("The batch writing threads is {}", batchWriteThreads);
+        LOG.debug("The batch writing threads is {}", BATCH_WRITE_THREADS);
         try {
             R result = commit(g, callable);
             this.batchMeter.mark(size);
             return result;
         } finally {
-            batchWriteThreads.decrementAndGet();
+            BATCH_WRITE_THREADS.decrementAndGet();
         }
     }
 
     @JsonIgnoreProperties(value = {"type"})
-    protected static abstract class JsonElement implements Checkable {
+    protected abstract static class JsonElement implements Checkable {
 
         @JsonProperty("id")
         public Object id;

hugegraph-api/src/main/java/com/baidu/hugegraph/api/gremlin/GremlinAPI.java

@@ -51,9 +51,9 @@
 @Singleton
 public class GremlinAPI extends API {
 
-    private static final Histogram gremlinInputHistogram =
+    private static final Histogram GREMLIN_INPUT_HISTOGRAM =
             MetricsUtil.registerHistogram(GremlinAPI.class, "gremlin-input");
-    private static final Histogram gremlinOutputHistogram =
+    private static final Histogram GREMLIN_OUTPUT_HISTOGRAM =
             MetricsUtil.registerHistogram(GremlinAPI.class, "gremlin-output");
 
     private static final Set<String> FORBIDDEN_REQUEST_EXCEPTIONS =
@@ -100,14 +100,14 @@ public Response post(@Context HugeConfig conf,
         // .build();
         String auth = headers.getHeaderString(HttpHeaders.AUTHORIZATION);
         Response response = this.client().doPostRequest(auth, request);
-        gremlinInputHistogram.update(request.length());
-        gremlinOutputHistogram.update(response.getLength());
+        GREMLIN_INPUT_HISTOGRAM.update(request.length());
+        GREMLIN_OUTPUT_HISTOGRAM.update(response.getLength());
         return transformResponseIfNeeded(response);
     }
 
     @GET
     @Timed
-    @Compress(buffer=(1024 * 40))
+    @Compress(buffer = (1024 * 40))
     @Produces(APPLICATION_JSON_WITH_CHARSET)
     public Response get(@Context HugeConfig conf,
                         @Context HttpHeaders headers,
@@ -116,8 +116,8 @@ public Response get(@Context HugeConfig conf,
         String query = uriInfo.getRequestUri().getRawQuery();
         MultivaluedMap<String, String> params = uriInfo.getQueryParameters();
         Response response = this.client().doGetRequest(auth, params);
-        gremlinInputHistogram.update(query.length());
-        gremlinOutputHistogram.update(response.getLength());
+        GREMLIN_INPUT_HISTOGRAM.update(query.length());
+        GREMLIN_OUTPUT_HISTOGRAM.update(response.getLength());
         return transformResponseIfNeeded(response);
     }
 

hugegraph-api/src/main/java/com/baidu/hugegraph/api/job/GremlinAPI.java

@@ -65,7 +65,7 @@ public class GremlinAPI extends API {
 
     private static final int MAX_NAME_LENGTH = 256;
 
-    private static final Histogram gremlinJobInputHistogram =
+    private static final Histogram GREMLIN_JOB_INPUT_HISTOGRAM =
             MetricsUtil.registerHistogram(GremlinAPI.class, "gremlin-input");
 
     @POST
@@ -79,7 +79,7 @@ public Map<String, Id> post(@Context GraphManager manager,
                                 GremlinRequest request) {
         LOG.debug("Graph [{}] schedule gremlin job: {}", graph, request);
         checkCreatingBody(request);
-        gremlinJobInputHistogram.update(request.gremlin.length());
+        GREMLIN_JOB_INPUT_HISTOGRAM.update(request.gremlin.length());
 
         HugeGraph g = graph(manager, graph);
         request.aliase(graph, "graph");

hugegraph-api/src/main/java/com/baidu/hugegraph/api/schema/IndexLabelAPI.java

@@ -104,8 +104,8 @@ public String update(@Context GraphManager manager,
 
         HugeGraph g = graph(manager, graph);
         IndexLabel.Builder builder = jsonIndexLabel.convert2Builder(g);
-        IndexLabel IndexLabel = append ? builder.append() : builder.eliminate();
-        return manager.serializer(g).writeIndexlabel(mapIndexLabel(IndexLabel));
+        IndexLabel indexLabel = append ? builder.append() : builder.eliminate();
+        return manager.serializer(g).writeIndexlabel(mapIndexLabel(indexLabel));
     }
 
     @GET

hugegraph-api/src/main/java/com/baidu/hugegraph/auth/HugeAuthenticator.java

@@ -68,6 +68,7 @@ public interface HugeAuthenticator extends Authenticator {
 
     public UserWithRole authenticate(String username, String password,
                                      String token);
+
     public AuthManager authManager();
 
     @Override

hugegraph-api/src/main/java/com/baidu/hugegraph/auth/HugeFactoryAuthProxy.java

@@ -68,7 +68,7 @@ public final class HugeFactoryAuthProxy {
     private static final Set<String> PROTECT_METHODS = ImmutableSet.of(
                                                        "instance");
 
-    private static final Map<HugeGraph, HugeGraph> graphs = new HashMap<>();
+    private static final Map<HugeGraph, HugeGraph> GRAPHS = new HashMap<>();
 
     static {
         HugeGraphAuthProxy.setContext(HugeGraphAuthProxy.Context.admin());
@@ -81,10 +81,10 @@ public static synchronized HugeGraph open(Configuration config) {
          * TODO: Add verify to StandardHugeGraph() to prevent dynamic creation
          */
         HugeGraph graph = HugeFactory.open(config);
-        HugeGraph proxy = graphs.get(graph);
+        HugeGraph proxy = GRAPHS.get(graph);
         if (proxy == null) {
             proxy = new HugeGraphAuthProxy(graph);
-            graphs.put(graph, proxy);
+            GRAPHS.put(graph, proxy);
         }
         return proxy;
     }
@@ -120,16 +120,16 @@ private static void registerPrivateActions() {
         Reflection.registerFieldsToFilter(com.baidu.hugegraph.auth.HugeGraphAuthProxy.ContextTask.class, "runner", "context");
         Reflection.registerFieldsToFilter(com.baidu.hugegraph.StandardHugeGraph.class, "LOG", "started", "closed", "mode", "variables", "name", "params", "configuration", "schemaEventHub", "graphEventHub", "indexEventHub", "writeRateLimiter", "readRateLimiter", "taskManager", "authManager", "features", "storeProvider", "tx", "ramtable", "$assertionsDisabled");
         Reflection.registerMethodsToFilter(com.baidu.hugegraph.StandardHugeGraph.class, "lambda$0", "access$3", "access$4", "access$2", "access$5", "access$6", "access$7", "waitUntilAllTasksCompleted", "access$8", "loadStoreProvider", "graphTransaction", "schemaTransaction", "openSchemaTransaction", "checkGraphNotClosed", "openSystemTransaction", "openGraphTransaction", "systemTransaction", "access$9", "access$10", "access$11", "access$12", "access$13", "access$14", "access$15", "access$16", "access$17", "access$18", "serializer", "loadSchemaStore", "loadSystemStore", "loadGraphStore", "closeTx", "analyzer", "serverInfoManager", "reloadRamtable", "reloadRamtable", "access$19", "access$20", "access$21");
-        Reflection.registerFieldsToFilter(c("com.baidu.hugegraph.StandardHugeGraph$StandardHugeGraphParams"), "graph", "this$0");
-        Reflection.registerMethodsToFilter(c("com.baidu.hugegraph.StandardHugeGraph$StandardHugeGraphParams"), "access$1", "graph");
-        Reflection.registerFieldsToFilter(c("com.baidu.hugegraph.StandardHugeGraph$TinkerPopTransaction"), "refs", "opened", "transactions", "this$0", "$assertionsDisabled");
-        Reflection.registerMethodsToFilter(c("com.baidu.hugegraph.StandardHugeGraph$TinkerPopTransaction"), "lambda$0", "access$3", "access$2", "lambda$1", "graphTransaction", "schemaTransaction", "systemTransaction", "access$1", "setOpened", "doCommit", "verifyOpened", "doRollback", "doClose", "destroyTransaction", "doOpen", "setClosed", "getOrNewTransaction", "access$0", "resetState");
+        Reflection.registerFieldsToFilter(loadClass("com.baidu.hugegraph.StandardHugeGraph$StandardHugeGraphParams"), "graph", "this$0");
+        Reflection.registerMethodsToFilter(loadClass("com.baidu.hugegraph.StandardHugeGraph$StandardHugeGraphParams"), "access$1", "graph");
+        Reflection.registerFieldsToFilter(loadClass("com.baidu.hugegraph.StandardHugeGraph$TinkerPopTransaction"), "refs", "opened", "transactions", "this$0", "$assertionsDisabled");
+        Reflection.registerMethodsToFilter(loadClass("com.baidu.hugegraph.StandardHugeGraph$TinkerPopTransaction"), "lambda$0", "access$3", "access$2", "lambda$1", "graphTransaction", "schemaTransaction", "systemTransaction", "access$1", "setOpened", "doCommit", "verifyOpened", "doRollback", "doClose", "destroyTransaction", "doOpen", "setClosed", "getOrNewTransaction", "access$0", "resetState");
         Reflection.registerFieldsToFilter(org.apache.tinkerpop.gremlin.structure.util.AbstractThreadLocalTransaction.class, "readWriteConsumerInternal", "closeConsumerInternal", "transactionListeners");
         Reflection.registerMethodsToFilter(org.apache.tinkerpop.gremlin.structure.util.AbstractThreadLocalTransaction.class, "doClose", "fireOnCommit", "fireOnRollback", "doReadWrite", "lambda$fireOnRollback$1", "lambda$fireOnCommit$0");
         Reflection.registerFieldsToFilter(org.apache.tinkerpop.gremlin.structure.util.AbstractTransaction.class, "g");
         Reflection.registerMethodsToFilter(org.apache.tinkerpop.gremlin.structure.util.AbstractTransaction.class, "doCommit", "doRollback", "doClose", "doOpen", "fireOnCommit", "fireOnRollback", "doReadWrite");
-        Reflection.registerFieldsToFilter(c("com.baidu.hugegraph.StandardHugeGraph$Txs"), "schemaTx", "systemTx", "graphTx", "openedTime", "$assertionsDisabled");
-        Reflection.registerMethodsToFilter(c("com.baidu.hugegraph.StandardHugeGraph$Txs"), "access$2", "access$1", "access$0");
+        Reflection.registerFieldsToFilter(loadClass("com.baidu.hugegraph.StandardHugeGraph$Txs"), "schemaTx", "systemTx", "graphTx", "openedTime", "$assertionsDisabled");
+        Reflection.registerMethodsToFilter(loadClass("com.baidu.hugegraph.StandardHugeGraph$Txs"), "access$2", "access$1", "access$0");
         Reflection.registerFieldsToFilter(com.baidu.hugegraph.backend.tx.GraphTransaction.class, "indexTx", "addedVertices", "removedVertices", "addedEdges", "removedEdges", "addedProps", "removedProps", "updatedVertices", "updatedEdges", "updatedOldestProps", "locksTable", "checkCustomVertexExist", "checkAdjacentVertexExist", "lazyLoadAdjacentVertex", "ignoreInvalidEntry", "commitPartOfAdjacentEdges", "batchSize", "pageSize", "verticesCapacity", "edgesCapacity", "$assertionsDisabled", "$SWITCH_TABLE$com$baidu$hugegraph$type$define$IdStrategy");
         Reflection.registerMethodsToFilter(com.baidu.hugegraph.backend.tx.GraphTransaction.class, "lambda$0", "lambda$1", "lambda$2", "lambda$3", "lambda$4", "lambda$5", "lambda$6", "lambda$7", "lambda$8", "lambda$9", "lambda$10", "lambda$11", "lambda$12", "lambda$13", "lambda$14", "lambda$15", "lambda$16", "lambda$17", "lambda$18", "lambda$19", "access$1", "$SWITCH_TABLE$com$baidu$hugegraph$type$define$IdStrategy", "indexTransaction", "indexTransaction", "beforeWrite", "prepareCommit", "verticesInTxSize", "edgesInTxSize", "checkTxVerticesCapacity", "checkTxEdgesCapacity", "verticesInTxUpdated", "verticesInTxRemoved", "removingEdgeOwner", "prepareDeletions", "prepareDeletions", "prepareUpdates", "prepareAdditions", "checkVertexExistIfCustomizedId", "checkAggregateProperty", "checkAggregateProperty", "checkNonnullProperty", "queryEdgesFromBackend", "commitPartOfEdgeDeletions", "optimizeQueries", "checkVertexLabel", "checkId", "queryVerticesFromBackend", "joinTxVertices", "joinTxEdges", "lockForUpdateProperty", "optimizeQuery", "verifyVerticesConditionQuery", "verifyEdgesConditionQuery", "indexQuery", "joinTxRecords", "propertyUpdated", "parseEntry", "traverseByLabel", "reset", "queryVerticesByIds", "filterUnmatchedRecords", "skipOffsetOrStopLimit", "filterExpiredResultFromFromBackend", "queryEdgesByIds", "matchEdgeSortKeys", "rightResultFromIndexQuery");
         Reflection.registerFieldsToFilter(com.baidu.hugegraph.backend.tx.IndexableTransaction.class, "$assertionsDisabled");
@@ -321,7 +321,7 @@ private static boolean registerClass(Class<?> clazz,
         return true;
     }
 
-    private static Class<?> c(String clazz) {
+    private static Class<?> loadClass(String clazz) {
         try {
             return Class.forName(clazz);
         } catch (ClassNotFoundException e) {

hugegraph-api/src/main/java/com/baidu/hugegraph/auth/HugeGraphAuthProxy.java

@@ -44,7 +44,6 @@
 import jakarta.ws.rs.NotAuthorizedException;
 
 import org.apache.commons.configuration2.Configuration;
-import org.apache.groovy.json.internal.MapItemValue;
 import org.apache.tinkerpop.gremlin.process.computer.GraphComputer;
 import org.apache.tinkerpop.gremlin.process.traversal.Bytecode;
 import org.apache.tinkerpop.gremlin.process.traversal.Bytecode.Instruction;
@@ -1749,17 +1748,17 @@ public String toString() {
         }
     }
 
-    private static final ThreadLocal<Context> contexts =
+    private static final ThreadLocal<Context> CONTEXTS =
                                               new InheritableThreadLocal<>();
 
     protected static final Context setContext(Context context) {
-        Context old = contexts.get();
-        contexts.set(context);
+        Context old = CONTEXTS.get();
+        CONTEXTS.set(context);
         return old;
     }
 
     protected static final void resetContext() {
-        contexts.remove();
+        CONTEXTS.remove();
     }
 
     protected static final Context getContext() {
@@ -1770,7 +1769,7 @@ protected static final Context getContext() {
             return new Context(user);
         }
 
-        return contexts.get();
+        return CONTEXTS.get();
     }
 
     protected static final String getContextString() {

hugegraph-api/src/main/java/com/baidu/hugegraph/license/LicenseVerifier.java

@@ -55,7 +55,7 @@ private LicenseVerifier() {
 
     public static LicenseVerifier instance() {
         if (INSTANCE == null) {
-            synchronized(LicenseVerifier.class) {
+            synchronized (LicenseVerifier.class) {
                 if (INSTANCE == null) {
                     INSTANCE = new LicenseVerifier();
                 }

hugegraph-api/src/main/java/com/baidu/hugegraph/metrics/MetricsUtil.java

@@ -30,27 +30,27 @@
 
 public class MetricsUtil {
 
-    private static final MetricRegistry registry =
+    private static final MetricRegistry REGISTRY =
                                         MetricManager.INSTANCE.getRegistry();
 
     public static <T> Gauge<T> registerGauge(Class<?> clazz, String name,
                                              Gauge<T> gauge) {
-        return registry.register(MetricRegistry.name(clazz, name), gauge);
+        return REGISTRY.register(MetricRegistry.name(clazz, name), gauge);
     }
 
     public static Counter registerCounter(Class<?> clazz, String name) {
-        return registry.counter(MetricRegistry.name(clazz, name));
+        return REGISTRY.counter(MetricRegistry.name(clazz, name));
     }
 
     public static Histogram registerHistogram(Class<?> clazz, String name) {
-        return registry.histogram(MetricRegistry.name(clazz, name));
+        return REGISTRY.histogram(MetricRegistry.name(clazz, name));
     }
 
     public static Meter registerMeter(Class<?> clazz, String name) {
-        return registry.meter(MetricRegistry.name(clazz, name));
+        return REGISTRY.meter(MetricRegistry.name(clazz, name));
     }
 
     public static Timer registerTimer(Class<?> clazz, String name) {
-        return registry.timer(MetricRegistry.name(clazz, name));
+        return REGISTRY.timer(MetricRegistry.name(clazz, name));
     }
 }

hugegraph-api/src/main/java/com/baidu/hugegraph/server/ApplicationConfig.java

@@ -101,16 +101,16 @@ private class GraphManagerFactory extends AbstractBinder
 
         public GraphManagerFactory(HugeConfig conf, EventHub hub) {
             register(new ApplicationEventListener() {
-                private final ApplicationEvent.Type EVENT_INITED =
+                private final ApplicationEvent.Type eventInited =
                               ApplicationEvent.Type.INITIALIZATION_FINISHED;
-                private final ApplicationEvent.Type EVENT_DESTROYED =
+                private final ApplicationEvent.Type eventDestroyed =
                               ApplicationEvent.Type.DESTROY_FINISHED;
 
                 @Override
                 public void onEvent(ApplicationEvent event) {
-                    if (event.getType() == this.EVENT_INITED) {
+                    if (event.getType() == this.eventInited) {
                         GraphManagerFactory.this.manager = new GraphManager(conf, hub);
-                    } else if (event.getType() == this.EVENT_DESTROYED) {
+                    } else if (event.getType() == this.eventDestroyed) {
                         if (GraphManagerFactory.this.manager != null) {
                             GraphManagerFactory.this.manager.close();
                         }