content: /*
   * Copyright 1999-2017 Alibaba Group Holding Ltd.
   *
   * 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.alibaba.druid.sql.ast;
  
  import com.alibaba.druid.sql.ast.statement.SQLSelectOrderByItem;
  import com.alibaba.druid.sql.visitor.SQLASTVisitor;
  
  import java.util.ArrayList;
  import java.util.List;
  
  public final class SQLOrderBy extends SQLObjectImpl implements SQLReplaceable {
      protected final List<SQLSelectOrderByItem> items = new ArrayList<SQLSelectOrderByItem>();
  
      // for postgres
      private boolean siblings;
  
      public SQLOrderBy() {
      }
  
      public SQLOrderBy(SQLExpr expr) {
          SQLSelectOrderByItem item = new SQLSelectOrderByItem(expr);
          addItem(item);
      }
  
      public SQLOrderBy(SQLExpr expr, SQLOrderingSpecification type) {
          SQLSelectOrderByItem item = new SQLSelectOrderByItem(expr, type);
          addItem(item);
      }
  
      public void addItem(SQLSelectOrderByItem item) {
          if (item != null) {
              item.setParent(this);
          }
          this.items.add(item);
      }
  
      public void addItem(SQLExpr item) {
          addItem(new SQLSelectOrderByItem(item));
      }
  
      public List<SQLSelectOrderByItem> getItems() {
          return this.items;
      }
  
      public boolean isSiblings() {
          return this.siblings;
      }
  
      public void setSiblings(boolean siblings) {
          this.siblings = siblings;
      }
  
      protected void accept0(SQLASTVisitor v) {
          if (v.visit(this)) {
              for (int i = 0; i < this.items.size(); i++) {
                  final SQLSelectOrderByItem item = this.items.get(i);
                  item.accept(v);
              }
          }
  
          v.endVisit(this);
      }
  
      @Override
      public boolean equals(Object o) {
          if (this == o) {
              return true;
          }
          if (o == null || getClass() != o.getClass()) {
              return false;
          }
  
          SQLOrderBy order = (SQLOrderBy) o;
  
          if (siblings != order.siblings) {
              return false;
          }
          return items.equals(order.items);
      }
  
      @Override
      public int hashCode() {
          int result = items.hashCode();
          result = 31 * result + (siblings ? 1 : 0);
          return result;
      }
  
      public void addItem(SQLExpr expr, SQLOrderingSpecification type) {
          SQLSelectOrderByItem item = createItem();
          item.setExpr(expr);
          item.setType(type);
          addItem(item);
      }
  
      @Override
      public boolean replace(SQLExpr expr, SQLExpr target) {
          for (SQLSelectOrderByItem item : items) {
              if (item.replace(expr, target)) {
                  return true;
              }
          }
  
          return false;
      }
  
      protected SQLSelectOrderByItem createItem() {
          return new SQLSelectOrderByItem();
      }
  
      public SQLOrderBy clone() {
          SQLOrderBy x = new SQLOrderBy();
  
          for (SQLSelectOrderByItem item : items) {
              SQLSelectOrderByItem item1 = item.clone();
              item1.setParent(x);
              x.items.add(item1);
          }
  
          x.siblings = siblings;
  
          return x;
      }
  }
  