remove reflection way

Signed-off-by: Lantao Jin <ltjin@amazon.com>

Author: LantaoJin

integ-test/src/yamlRestTest/resources/rest-api-spec/test/issues/4173.yml

@@ -28,12 +28,20 @@ setup:
                     type: keyword
                   child_num:
                     type: integer
+  - do:
+      bulk:
+        index: array-test
+        refresh: true
+        body:
+          - '{"index": {}}'
+          - '{"array_text": ["Jane Smith","hello world"],"array_keyword": [ "c++", "java" ],"array_num": [1, 2],"array_boolean": [true, false],"array_date": ["2023-01-02T22:03:34.000Z","2023-01-02T22:03:35.000Z"],"num" : 10,"parent": {"child_array_num": [1.1, 2.2], "child_array_keyword":["a a a", "b b b"], "child_num": 100}}'
+          - '{"index": {}}'
+          - '{"array_text": "OpenSearch PPL","array_keyword": "python","array_num": 3,"array_boolean": true,"array_date": "2023-01-02T22:03:36.000Z","num" : 11,"parent": {"child_array_num": 3.3, "child_array_keyword":"c c c", "child_num": 101}}'
   - do:
       query.settings:
         body:
           transient:
             plugins.calcite.enabled : true
-
 ---
 teardown:
   - do:
@@ -48,15 +56,6 @@ teardown:
       features:
         - headers
         - allowed_warnings
-  - do:
-      bulk:
-        index: array-test
-        refresh: true
-        body:
-          - '{"index": {}}'
-          - '{"array_text": ["Jane Smith","hello world"],"array_keyword": [ "c++", "java" ],"array_num": [1, 2],"array_boolean": [true, false],"array_date": ["2023-01-02T22:03:34.000Z","2023-01-02T22:03:35.000Z"],"num" : 10,"parent": {"child_array_num": [1.1, 2.2], "child_array_keyword":["a a a", "b b b"], "child_num": 100}}'
-          - '{"index": {}}'
-          - '{"array_text": "OpenSearch PPL","array_keyword": "python","array_num": 3,"array_boolean": true,"array_date": "2023-01-02T22:03:36.000Z","num" : 11,"parent": {"child_array_num": 3.3, "child_array_keyword":"c c c", "child_num": 101}}'
   - do:
       allowed_warnings:
         - 'Loading the fielddata on the _id field is deprecated and will be removed in future versions. If you require sorting or aggregating on this field you should also include the id in the body of your documents, and map this field as a keyword field that has [doc_values] enabled'

opensearch/src/main/java/org/opensearch/sql/opensearch/executor/OpenSearchExecutionEngine.java

@@ -6,7 +6,6 @@
 package org.opensearch.sql.opensearch.executor;
 
 import com.google.common.base.Suppliers;
-import java.lang.reflect.Method;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.ResultSetMetaData;
@@ -20,8 +19,6 @@
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Supplier;
-import org.apache.calcite.avatica.AvaticaResultSet;
-import org.apache.calcite.avatica.util.Cursor;
 import org.apache.calcite.plan.RelOptUtil;
 import org.apache.calcite.rel.RelNode;
 import org.apache.calcite.rel.RelRoot;
@@ -218,29 +215,6 @@ public void execute(
         });
   }
 
-  /**
-   * Retrieves column accessors from AvaticaResultSet using reflection. This method accesses the
-   * private getAccessor method to obtain direct access to column data.
-   *
-   * @param rs the ResultSet to get accessors from
-   * @param columnCount the number of columns in the ResultSet
-   * @return list of Cursor.Accessor objects for each column
-   * @throws SQLException if reflection fails or column access is invalid
-   */
-  private List<Cursor.Accessor> getAccessors(ResultSet rs, int columnCount) throws SQLException {
-    List<Cursor.Accessor> accessorList = new ArrayList<>();
-    try {
-      Method method = AvaticaResultSet.class.getDeclaredMethod("getAccessor", int.class);
-      method.setAccessible(true);
-      for (int i = 1; i <= columnCount; i++) {
-        accessorList.add((Cursor.Accessor) method.invoke(rs, i));
-      }
-    } catch (Exception e) {
-      throw new SQLException("Unable to get accessors", e);
-    }
-    return accessorList;
-  }
-
   /**
    * Process values recursively, handling geo points and nested maps. Geo points are converted to
    * OpenSearchExprGeoPointValue. Maps are recursively processed to handle nested structures.
@@ -282,7 +256,6 @@ private void buildResultSet(
     // Get the ResultSet metadata to know about columns
     ResultSetMetaData metaData = resultSet.getMetaData();
     int columnCount = metaData.getColumnCount();
-    List<Cursor.Accessor> accessorList = getAccessors(resultSet, columnCount);
     List<RelDataType> fieldTypes =
         rowTypes.getFieldList().stream().map(RelDataTypeField::getType).toList();
     List<ExprValue> values = new ArrayList<>();
@@ -292,7 +265,7 @@ private void buildResultSet(
       // Loop through each column
       for (int i = 1; i <= columnCount; i++) {
         String columnName = metaData.getColumnName(i);
-        Object value = accessorList.get(i - 1).getObject();
+        Object value = resultSet.getObject(columnName);
         Object converted = processValue(value);
         ExprValue exprValue = ExprValueUtils.fromObjectValue(converted);
         row.put(columnName, exprValue);