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.*;
  import com.alibaba.druid.sql.ast.statement.SQLColumnDefinition;
  import com.alibaba.druid.sql.visitor.SQLASTVisitor;
  import com.alibaba.druid.util.FnvHash;
  
  import java.util.Collections;
  import java.util.List;
  
  public class SQLDbLinkExpr extends SQLExprImpl implements SQLName, SQLExpr, SQLReplaceable {
      private SQLExpr expr;
      private String dbLink;
  
      private long dbLinkHashCode64;
      private long hashCode64;
  
      public SQLDbLinkExpr() {
      }
  
      public String getSimpleName() {
          return dbLink;
      }
  
      public SQLExpr getExpr() {
          return this.expr;
      }
  
      public void setExpr(SQLExpr expr) {
          this.expr = expr;
      }
  
      public String getDbLink() {
          return this.dbLink;
      }
  
      public void setDbLink(String dbLink) {
          this.dbLink = dbLink;
      }
  
      @Override
      protected void accept0(SQLASTVisitor visitor) {
          if (visitor.visit(this)) {
              acceptChild(visitor, this.expr);
          }
  
          visitor.endVisit(this);
      }
  
      @Override
      public boolean replace(SQLExpr expr, SQLExpr target) {
          if (this.expr == expr) {
              setExpr(target);
              return true;
          }
          return false;
      }
  
      @Override
      public List<SQLObject> getChildren() {
          return Collections.<SQLObject>singletonList(this.expr);
      }
  
      @Override
      public int hashCode() {
          long value = hashCode64();
          return (int) (value ^ (value >>> 32));
      }
  
      @Override
      public boolean equals(Object obj) {
          if (this == obj) {
              return true;
          }
          if (obj == null) {
              return false;
          }
          if (getClass() != obj.getClass()) {
              return false;
          }
          SQLDbLinkExpr other = (SQLDbLinkExpr) obj;
          return this.hashCode64() == other.hashCode64();
      }
  
      public SQLDbLinkExpr clone() {
          SQLDbLinkExpr x = new SQLDbLinkExpr();
          if (expr != null) {
              x.setExpr(expr.clone());
          }
          x.dbLink = dbLink;
          return x;
      }
  
      public long nameHashCode64() {
          if (dbLinkHashCode64 == 0
                  && dbLink != null) {
              dbLinkHashCode64 = FnvHash.hashCode64(dbLink);
          }
          return dbLinkHashCode64;
      }
  
      @Override
      public long hashCode64() {
          if (hashCode64 == 0) {
              long hash;
              if (expr instanceof SQLName) {
                  hash = ((SQLName) expr).hashCode64();
  
                  hash ^= '@';
                  hash *= FnvHash.PRIME;
              } else if (expr == null) {
                  hash = FnvHash.BASIC;
              } else {
                  hash = FnvHash.fnv1a_64_lower(expr.toString());
  
                  hash ^= '@';
                  hash *= FnvHash.PRIME;
              }
              hash = FnvHash.hashCode64(hash, dbLink);
              hashCode64 = hash;
          }
  
          return hashCode64;
      }
  
      @Override
      public SQLColumnDefinition getResolvedColumn() {
          return null;
      }
  }
  