minor improvements

Author: fsk119

flink-table/flink-table-planner/src/main/java/org/apache/flink/table/planner/plan/nodes/exec/common/CommonExecLookupJoin.java

@@ -624,7 +624,7 @@ protected ProcessFunction<RowData, RowData> createSyncLookupJoinFunction(
         RowType rightRowType =
                 getRightOutputRowType(projectionOutputRelDataType, tableSourceRowType);
         GeneratedCollector<ListenableCollector<RowData>> generatedCollector =
-                FunctionCallCodeGenerator.generateCollector(
+                LookupJoinCodeGenerator.generateCollector(
                         new CodeGeneratorContext(config, classLoader),
                         inputRowType,
                         rightRowType,

flink-table/flink-table-planner/src/main/scala/org/apache/flink/table/planner/codegen/LookupJoinCodeGenerator.scala

@@ -234,6 +234,24 @@ object LookupJoinCodeGenerator {
     }
   }
 
+  def generateCollector(
+      ctx: CodeGeneratorContext,
+      inputRowType: RowType,
+      rightRowType: RowType,
+      resultRowType: RowType,
+      condition: Option[RexNode],
+      pojoFieldMapping: Option[Array[Int]],
+      retainHeader: Boolean = true): GeneratedCollector[ListenableCollector[RowData]] = {
+    FunctionCallCodeGenerator.generateCollector(
+      ctx,
+      inputRowType,
+      rightRowType,
+      resultRowType,
+      condition,
+      pojoFieldMapping,
+      retainHeader)
+  }
+
   /**
    * Generates a [[TableFunctionResultFuture]] that can be passed to Java compiler.
    *