Add scaffold CsvIOParseHelpers (apache#31720)

sdks/java/io/csv/src/main/java/org/apache/beam/sdk/io/csv/CsvIOParseHelpers.java

@@ -0,0 +1,55 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.beam.sdk.io.csv;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.beam.sdk.schemas.Schema;
+import org.apache.commons.csv.CSVFormat;
+
+/** A utility class containing shared methods for parsing CSV records. */
+final class CsvIOParseHelpers {
+  /** Validate the {@link CSVFormat} for CSV record parsing requirements. */
+  // TODO(https://github.com/apache/beam/issues/31712): implement method.
+  static void validate(CSVFormat format) {}
+
+  /**
+   * Validate the {@link CSVFormat} in relation to the {@link Schema} for CSV record parsing
+   * requirements.
+   */
+  // TODO(https://github.com/apache/beam/issues/31716): implement method.
+  static void validate(CSVFormat format, Schema schema) {}
+
+  /**
+   * Build a {@link List} of {@link Schema.Field}s corresponding to the expected position of each
+   * field within the CSV record.
+   */
+  // TODO(https://github.com/apache/beam/issues/31718): implement method.
+  static List<Schema.Field> mapFieldPositions(CSVFormat format, Schema schema) {
+    return new ArrayList<>();
+  }
+
+  /**
+   * Parse the given {@link String} cell of the CSV record based on the given field's {@link
+   * Schema.FieldType}.
+   */
+  // TODO(https://github.com/apache/beam/issues/31719): implement method.
+  static Object parseCell(String cell, Schema.Field field) {
+    return "";
+  }
+}