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.expr;
  
  import com.alibaba.druid.sql.ast.SQLDataType;
  import com.alibaba.druid.sql.ast.SQLExprImpl;
  import com.alibaba.druid.sql.ast.SQLObject;
  import com.alibaba.druid.sql.ast.statement.SQLSelect;
  import com.alibaba.druid.sql.ast.statement.SQLSelectItem;
  import com.alibaba.druid.sql.ast.statement.SQLSelectQueryBlock;
  import com.alibaba.druid.sql.visitor.SQLASTVisitor;
  
  import java.util.Collections;
  import java.util.List;
  
  public class SQLAnyExpr extends SQLExprImpl {
      public SQLSelect subQuery;
  
      public SQLAnyExpr() {
      }
  
      public SQLAnyExpr(SQLSelect select) {
          setSubQuery(select);
      }
  
      public SQLAnyExpr clone() {
          SQLAnyExpr x = new SQLAnyExpr();
          if (subQuery != null) {
              x.setSubQuery(subQuery.clone());
          }
          return x;
      }
  
      public SQLSelect getSubQuery() {
          return this.subQuery;
      }
  
      public void setSubQuery(SQLSelect x) {
          if (x != null) {
              x.setParent(this);
          }
          this.subQuery = x;
      }
  
      @Override
      protected void accept0(SQLASTVisitor visitor) {
          if (visitor.visit(this)) {
              if (this.subQuery != null) {
                  this.subQuery.accept(visitor);
              }
          }
  
          visitor.endVisit(this);
      }
  
      public List<SQLObject> getChildren() {
          return Collections.<SQLObject>singletonList(this.subQuery);
      }
  
      @Override
      public int hashCode() {
          final int prime = 31;
          int result = 1;
          result = prime * result + ((subQuery == null) ? 0 : subQuery.hashCode());
          return result;
      }
  
      @Override
      public boolean equals(Object obj) {
          if (this == obj) {
              return true;
          }
          if (obj == null) {
              return false;
          }
          if (getClass() != obj.getClass()) {
              return false;
          }
          SQLAnyExpr other = (SQLAnyExpr) obj;
          if (subQuery == null) {
              if (other.subQuery != null) {
                  return false;
              }
          } else if (!subQuery.equals(other.subQuery)) {
              return false;
          }
          return true;
      }
  
      public SQLDataType computeDataType() {
          if (subQuery == null) {
              return null;
          }
  
          SQLSelectQueryBlock queryBlock = subQuery.getFirstQueryBlock();
          if (queryBlock == null) {
              return null;
          }
  
          List<SQLSelectItem> selectList = queryBlock.getSelectList();
          if (selectList.size() == 1) {
              return selectList.get(0).computeDataType();
          }
  
          return null;
      }
  }
  