fix: adjust the code style and naming convention

hugegraph-api/src/main/java/org/apache/hugegraph/api/API.java

@@ -18,18 +18,18 @@
 package org.apache.hugegraph.api;
 
 import java.util.Collection;
-import java.util.HashMap;
-import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.concurrent.Callable;
 import java.util.function.Consumer;
 
+import org.apache.commons.lang.mutable.MutableLong;
 import org.apache.hugegraph.HugeException;
 import org.apache.hugegraph.HugeGraph;
 import org.apache.hugegraph.core.GraphManager;
 import org.apache.hugegraph.define.Checkable;
 import org.apache.hugegraph.metrics.MetricsUtil;
 import org.apache.hugegraph.util.E;
+import org.apache.hugegraph.util.InsertionOrderUtil;
 import org.apache.hugegraph.util.JsonUtil;
 import org.apache.hugegraph.util.Log;
 import org.slf4j.Logger;
@@ -44,35 +44,30 @@
 
 public class API {
 
-    protected static final Logger LOG = Log.logger(API.class);
-
     public static final String CHARSET = "UTF-8";
-
     public static final String TEXT_PLAIN = MediaType.TEXT_PLAIN;
     public static final String APPLICATION_JSON = MediaType.APPLICATION_JSON;
     public static final String APPLICATION_JSON_WITH_CHARSET =
-                               APPLICATION_JSON + ";charset=" + CHARSET;
+            APPLICATION_JSON + ";charset=" + CHARSET;
     public static final String JSON = MediaType.APPLICATION_JSON_TYPE
-                                               .getSubtype();
-
+            .getSubtype();
     public static final String ACTION_APPEND = "append";
     public static final String ACTION_ELIMINATE = "eliminate";
     public static final String ACTION_CLEAR = "clear";
-
+    protected static final Logger LOG = Log.logger(API.class);
     private static final Meter SUCCEED_METER =
-                         MetricsUtil.registerMeter(API.class, "commit-succeed");
+            MetricsUtil.registerMeter(API.class, "commit-succeed");
     private static final Meter ILLEGAL_ARG_ERROR_METER =
-                         MetricsUtil.registerMeter(API.class, "illegal-arg");
+            MetricsUtil.registerMeter(API.class, "illegal-arg");
     private static final Meter EXPECTED_ERROR_METER =
-                         MetricsUtil.registerMeter(API.class, "expected-error");
+            MetricsUtil.registerMeter(API.class, "expected-error");
     private static final Meter UNKNOWN_ERROR_METER =
-                         MetricsUtil.registerMeter(API.class, "unknown-error");
+            MetricsUtil.registerMeter(API.class, "unknown-error");
 
     public static HugeGraph graph(GraphManager manager, String graph) {
         HugeGraph g = manager.graph(graph);
         if (g == null) {
-            throw new NotFoundException(String.format(
-                      "Graph '%s' does not exist",  graph));
+            throw new NotFoundException(String.format("Graph '%s' does not exist", graph));
         }
         return g;
     }
@@ -142,8 +137,7 @@ protected static void checkUpdatingBody(Checkable body) {
         body.checkUpdate();
     }
 
-    protected static void checkCreatingBody(
-                          Collection<? extends Checkable> bodies) {
+    protected static void checkCreatingBody(Collection<? extends Checkable> bodies) {
         E.checkArgumentNotNull(bodies, "The request body can't be empty");
         for (Checkable body : bodies) {
             E.checkArgument(body != null,
@@ -152,8 +146,7 @@ protected static void checkCreatingBody(
         }
     }
 
-    protected static void checkUpdatingBody(
-                          Collection<? extends Checkable> bodies) {
+    protected static void checkUpdatingBody(Collection<? extends Checkable> bodies) {
         E.checkArgumentNotNull(bodies, "The request body can't be empty");
         for (Checkable body : bodies) {
             E.checkArgumentNotNull(body,
@@ -188,41 +181,51 @@ public static boolean checkAndParseAction(String action) {
         } else if (action.equals(ACTION_ELIMINATE)) {
             return false;
         } else {
-            throw new NotSupportedException(
-                      String.format("Not support action '%s'", action));
+            throw new NotSupportedException(String.format("Not support action '%s'", action));
         }
     }
 
-    public static class ApiMeasure {
-        public static final String EDGE_ITER = "edge_iters";
-        public static final String VERTICE_ITER = "vertice_iters";
+    public static class ApiMeasurer {
+
+        public static final String EDGE_ITER = "edge_iterations";
+        public static final String VERTICE_ITER = "vertice_iterations";
         public static final String COST = "cost";
-        protected long timeStart = System.currentTimeMillis();
-        protected HashMap<String, Object> mapResult = new LinkedHashMap<>();
+        private final long timeStart;
+        private final Map<String, Object> measures;
+
+        public ApiMeasurer() {
+            this.timeStart = System.currentTimeMillis();
+            this.measures = InsertionOrderUtil.newMap();
+        }
 
-        public Map<String, Object> getResult() {
-            mapResult.put(COST, System.currentTimeMillis() - timeStart);
-            return mapResult;
+        public Map<String, Object> measures() {
+            measures.put(COST, System.currentTimeMillis() - timeStart);
+            return measures;
         }
 
         public void put(String key, String value) {
-            this.mapResult.put(key, value);
+            this.measures.put(key, value);
         }
 
         public void put(String key, long value) {
-            this.mapResult.put(key, value);
+            this.measures.put(key, value);
         }
 
         public void put(String key, int value) {
-            this.mapResult.put(key, value);
+            this.measures.put(key, value);
         }
 
         protected void addCount(String key, long value) {
-            long cur = 0;
-            if (this.mapResult.containsKey(key)) {
-                cur = (long) this.mapResult.get(key);
+            Object current = measures.get(key);
+            if (current == null) {
+                measures.put(key, new MutableLong(value));
+            } else if (current instanceof MutableLong) {
+                MutableLong currentMutableLong = (MutableLong) current;
+                currentMutableLong.add(value);
+            } else if (current instanceof Long) {
+                Long currentLong = (Long) current;
+                measures.put(key, new MutableLong(currentLong + value));
             }
-            this.mapResult.put(key, cur + value);
         }
 
         public void addIterCount(long verticeIters, long edgeIters) {

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/AllShortestPathsAPI.java

@@ -85,7 +85,7 @@ public String get(@Context GraphManager manager,
                   graph, source, target, direction, edgeLabel, depth,
                   maxDegree, skipDegree, capacity, withVertex, withEdge);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         Id sourceId = VertexAPI.checkAndParseVertexId(source);
         Id targetId = VertexAPI.checkAndParseVertexId(target);
@@ -96,9 +96,9 @@ public String get(@Context GraphManager manager,
         ShortestPathTraverser traverser = new ShortestPathTraverser(g);
         List<String> edgeLabels = edgeLabel == null ? ImmutableList.of() :
                                   ImmutableList.of(edgeLabel);
-        HugeTraverser.PathSet paths = traverser.allShortestPaths(
-                sourceId, targetId, dir, edgeLabels,
-                depth, maxDegree, skipDegree, capacity);
+        HugeTraverser.PathSet paths = traverser.allShortestPaths(sourceId, targetId, dir,
+                                                                 edgeLabels, depth, maxDegree,
+                                                                 skipDegree, capacity);
 
         measure.addIterCount(traverser.vertexIterCounter.get(),
                              traverser.edgeIterCounter.get());
@@ -123,7 +123,7 @@ public String get(@Context GraphManager manager,
             iterEdge = HugeTraverser.EdgeRecord.getEdgeIds(edges).iterator();
         }
 
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writePaths("paths", paths, false,
                                   iterVertex, iterEdge);
     }

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/CrosspointsAPI.java

@@ -74,7 +74,7 @@ public String get(@Context GraphManager manager,
                   graph, source, target, direction, edgeLabel,
                   depth, maxDegree, capacity, limit);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
         Id sourceId = VertexAPI.checkAndParseVertexId(source);
         Id targetId = VertexAPI.checkAndParseVertexId(target);
         Directions dir = Directions.convert(EdgeAPI.parseDirection(direction));
@@ -87,7 +87,7 @@ public String get(@Context GraphManager manager,
                                                       limit);
         measure.addIterCount(traverser.vertexIterCounter.get(),
                              traverser.edgeIterCounter.get());
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writePaths("crosspoints", paths, true);
     }
 }

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/CustomizedCrosspointsAPI.java

@@ -65,11 +65,10 @@ public class CustomizedCrosspointsAPI extends API {
     private static List<CustomizedCrosspointsTraverser.PathPattern> pathPatterns(
             HugeGraph graph, CrosspointsRequest request) {
         int stepSize = request.pathPatterns.size();
-        List<CustomizedCrosspointsTraverser.PathPattern> pathPatterns;
-        pathPatterns = new ArrayList<>(stepSize);
+        List<CustomizedCrosspointsTraverser.PathPattern> pathPatterns = new ArrayList<>(stepSize);
         for (PathPattern pattern : request.pathPatterns) {
-            CustomizedCrosspointsTraverser.PathPattern pathPattern;
-            pathPattern = new CustomizedCrosspointsTraverser.PathPattern();
+            CustomizedCrosspointsTraverser.PathPattern pathPattern =
+                    new CustomizedCrosspointsTraverser.PathPattern();
             for (Step step : pattern.steps) {
                 pathPattern.add(step.jsonToStep(graph));
             }
@@ -100,7 +99,7 @@ public String post(@Context GraphManager manager,
                   graph, request.sources, request.pathPatterns, request.withPath,
                   request.withVertex, request.capacity, request.limit, request.withEdge);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         HugeGraph g = graph(manager, graph);
         Iterator<Vertex> sources = request.sources.vertices(g);
@@ -142,7 +141,7 @@ public String post(@Context GraphManager manager,
             }
         }
 
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writeCrosspoints(paths, iterVertex,
                                         iterEdge, request.withPath);
     }

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/CustomizedPathsAPI.java

@@ -96,7 +96,7 @@ public String post(@Context GraphManager manager,
                   request.sortBy, request.capacity, request.limit,
                   request.withVertex, request.withEdge);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         HugeGraph g = graph(manager, graph);
         Iterator<Vertex> sources = request.sources.vertices(g);
@@ -136,7 +136,7 @@ public String post(@Context GraphManager manager,
             iterEdge = HugeTraverser.EdgeRecord.getEdgeIds(edges).iterator();
         }
 
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writePaths("paths", paths, false,
                                   iterVertex, iterEdge);
     }

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/FusiformSimilarityAPI.java

@@ -95,7 +95,7 @@ public String post(@Context GraphManager manager,
                   request.minNeighbors, request.alpha, request.minSimilars,
                   request.groupProperty, request.minGroups);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
         HugeGraph g = graph(manager, graph);
         Iterator<Vertex> sources = request.sources.vertices(g);
         E.checkArgument(sources != null && sources.hasNext(),
@@ -125,7 +125,7 @@ public String post(@Context GraphManager manager,
             iterVertex = vertexIds.iterator();
         }
 
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writeSimilars(result, iterVertex);
     }
 

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/JaccardSimilarityAPI.java

@@ -74,7 +74,7 @@ public String get(@Context GraphManager manager,
                   "with direction {}, edge label {} and max degree '{}'",
                   graph, vertex, other, direction, edgeLabel, maxDegree);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         Id sourceId = VertexAPI.checkAndParseVertexId(vertex);
         Id targetId = VertexAPI.checkAndParseVertexId(other);
@@ -90,7 +90,7 @@ public String get(@Context GraphManager manager,
                                  traverser.edgeIterCounter.get());
         }
 
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writeMap(ImmutableMap.of("jaccard_similarity", similarity));
     }
 
@@ -114,7 +114,7 @@ public String post(@Context GraphManager manager,
                   graph, request.vertex, request.step,
                   request.top, request.capacity);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         HugeGraph g = graph(manager, graph);
         Id sourceId = HugeVertex.getIdValue(request.vertex);
@@ -129,7 +129,7 @@ public String post(@Context GraphManager manager,
             measure.addIterCount(traverser.vertexIterCounter.get(),
                                  traverser.edgeIterCounter.get());
         }
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writeMap(ImmutableMap.of("jaccard_similarity", results));
     }
 

hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/KneighborAPI.java

@@ -89,7 +89,7 @@ public String get(@Context GraphManager manager,
                   graph, sourceV, direction, edgeLabel, depth,
                   maxDegree, limit);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         Id source = VertexAPI.checkAndParseVertexId(sourceV);
         Directions dir = Directions.convert(EdgeAPI.parseDirection(direction));
@@ -104,10 +104,10 @@ public String get(@Context GraphManager manager,
                                  traverser.edgeIterCounter.get());
         }
         if (countOnly) {
-            return manager.serializer(g, measure.getResult()).writeMap(
-                    ImmutableMap.of("vertices_size", ids.size()));
+            return manager.serializer(g, measure.measures())
+                          .writeMap(ImmutableMap.of("vertices_size", ids.size()));
         }
-        return manager.serializer(g, measure.getResult()).writeList("vertices", ids);
+        return manager.serializer(g, measure.measures()).writeList("vertices", ids);
     }
 
     @POST
@@ -134,7 +134,7 @@ public String post(@Context GraphManager manager,
                   request.countOnly, request.withVertex, request.withPath,
                   request.withEdge);
 
-        ApiMeasure measure = new ApiMeasure();
+        ApiMeasurer measure = new ApiMeasurer();
 
         HugeGraph g = graph(manager, graph);
         Id sourceId = HugeVertex.getIdValue(request.source);
@@ -163,7 +163,7 @@ public String post(@Context GraphManager manager,
         }
 
         if (request.countOnly) {
-            return manager.serializer(g, measure.getResult())
+            return manager.serializer(g, measure.measures())
                           .writeNodesWithPath("kneighbor", neighbors, size, paths,
                                               QueryResults.emptyIterator(),
                                               QueryResults.emptyIterator());
@@ -193,7 +193,7 @@ public String post(@Context GraphManager manager,
             }
         }
 
-        return manager.serializer(g, measure.getResult())
+        return manager.serializer(g, measure.measures())
                       .writeNodesWithPath("kneighbor", neighbors,
                                           size, paths, iterVertex, iterEdge);
     }