content: /*
   * Copyright 1999-2012 Alibaba Group.
   *  
   * 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.
   */
  /**
   * (created at 2012-8-13)
   */
  package com.alibaba.cobar.parser.ast.fragment.ddl.index;
  
  import java.util.Collections;
  import java.util.List;
  
  import com.alibaba.cobar.parser.ast.ASTNode;
  import com.alibaba.cobar.parser.visitor.SQLASTVisitor;
  
  /**
   * @author <a href="mailto:shuo.qius@alibaba-inc.com">QIU Shuo</a>
   */
  public class IndexDefinition implements ASTNode {
      public static enum IndexType {
          BTREE,
          HASH
      }
  
      private final IndexType indexType;
      private final List<IndexColumnName> columns;
      private final List<IndexOption> options;
  
      @SuppressWarnings("unchecked")
      public IndexDefinition(IndexType indexType, List<IndexColumnName> columns, List<IndexOption> options) {
          this.indexType = indexType;
          if (columns == null || columns.isEmpty())
              throw new IllegalArgumentException("columns is null or empty");
          this.columns = columns;
          this.options = (List<IndexOption>) (options == null || options.isEmpty() ? Collections.emptyList() : options);
      }
  
      public IndexType getIndexType() {
          return indexType;
      }
  
      /**
       * @return never null
       */
      public List<IndexColumnName> getColumns() {
          return columns;
      }
  
      /**
       * @return never null
       */
      public List<IndexOption> getOptions() {
          return options;
      }
  
      @Override
      public void accept(SQLASTVisitor visitor) {
          // QS_TODO
  
      }
  
  }
  