/*
 * Copyright 2010-2012 Luca Garulli (l.garulli--at--orientechnologies.com)
 *
 * Licensed 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.orientechnologies.orient.core.sql;

import java.util.Iterator;
import java.util.List;
import java.util.Map;

import com.orientechnologies.orient.core.db.record.OIdentifiable;

/**
 * Abstract class that early executes the command and provide the iterator interface on top of the resultset.
 * 
 * @author Luca Garulli
 */
@SuppressWarnings("unchecked")
public abstract class OCommandExecutorSQLEarlyResultsetAbstract extends OCommandExecutorSQLResultsetAbstract {
  private Iterator<OIdentifiable> iterator;

  public Iterator<OIdentifiable> iterator() {
    return iterator(null);
  }

  @Override
  public Iterator<OIdentifiable> iterator(Map<Object, Object> iArgs) {
    if (iterator == null) {
      if (tempResult == null)
        tempResult = (List<OIdentifiable>) execute(iArgs);
      iterator = tempResult.iterator();
    }
    return iterator;
  }
}
