content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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 org.apache.carbondata.core.scan.expression.logical;
  
  import org.apache.carbondata.core.metadata.datatype.DataTypes;
  import org.apache.carbondata.core.scan.expression.Expression;
  import org.apache.carbondata.core.scan.expression.ExpressionResult;
  import org.apache.carbondata.core.scan.expression.LiteralExpression;
  import org.apache.carbondata.core.scan.expression.conditional.BinaryConditionalExpression;
  import org.apache.carbondata.core.scan.filter.intf.ExpressionType;
  import org.apache.carbondata.core.scan.filter.intf.RowIntf;
  
  /**
   * This class will form an expression whose evaluation will be always true.
   */
  public class TrueExpression extends BinaryConditionalExpression {
  
  
    private static final long serialVersionUID = -8390184061336799370L;
  
    public TrueExpression(Expression child1) {
      super(child1, new LiteralExpression(null, null));
    }
  
    /**
     * This method will always return false, mainly used in the filter expressions
     * which are illogical.
     * eg: columnName NOT IN('Java',NULL)
     * @param value
     * @return
     */
    @Override
    public ExpressionResult evaluate(RowIntf value) {
      return new ExpressionResult(DataTypes.BOOLEAN, true);
    }
  
    /**
     * This method will return the expression types
     * @return
     */
    @Override
    public ExpressionType getFilterExpressionType() {
      return ExpressionType.TRUE;
    }
  
    @Override
    public String getString() {
      return "True(" + (null == left ? null : left.getString());
    }
  
    @Override
    public String getStatement() {
      return "true";
    }
  }
  