content: /*
   * 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 com.aliyun.odps.lot.operators;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import com.aliyun.odps.lot.common.ArgumentNullException;
  import com.aliyun.odps.lot.common.Resource;
  import com.aliyun.odps.lot.common.ScalarExpression;
  import com.aliyun.odps.lot.common.Schema;
  
  public abstract class Transform extends Operator {
  
    private List<ScalarExpression> parameters;
    private List<Resource> resources;
    private Schema schema;
  
    public List<ScalarExpression> getParameters() {
      return parameters;
    }
  
    public List<Resource> getResources() {
      return resources;
    }
  
    public Schema getSchema() {
      return schema;
    }
  
    public Transform(List<ScalarExpression> parameters, List<Resource> resources, Schema schema) {
      if (parameters == null) {
        this.parameters = new ArrayList<ScalarExpression>();
      } else {
        this.parameters = parameters;
      }
  
      if (schema == null) {
        throw new ArgumentNullException("schema");
      }
  
      if (resources == null) {
        this.resources = new ArrayList<Resource>();
      } else {
        this.resources = resources;
      }
  
      this.schema = schema;
    }
  }
  