bug fixed for jsonpath, for issue #2306

src/main/java/com/alibaba/fastjson/JSONPath.java

@@ -1369,10 +1369,13 @@ Object parseArrayAccessFilter(boolean acceptBracket) {
             }
 
             int start = pos - 1;
+            char startCh = ch;
             while (ch != ']' && ch != '/' && !isEOF()) {
                 if (ch == '.' //
                         && (!predicateFlag) // 
-                        && !predicateFlag) {
+                        && !predicateFlag
+                        && startCh != '\''
+                ) {
                     break;
                 }
 

src/test/java/com/alibaba/json/bvt/issue_2300/Issue2306.java

@@ -0,0 +1,16 @@
+package com.alibaba.json.bvt.issue_2300;
+
+import com.alibaba.fastjson.JSONObject;
+import com.alibaba.fastjson.JSONPath;
+import junit.framework.TestCase;
+
+public class Issue2306 extends TestCase {
+    public void test_for_issue() throws Exception {
+        JSONObject object = new JSONObject();
+        object.put("help_score_avg.cbm", 123);
+
+        assertEquals(123
+            , JSONPath.extract(
+                    object.toJSONString(), "['help_score_avg.cbm']"));
+    }
+}