geode-core/src/main/java/org/apache/geode/cache/query/internal/CompiledLiteral.java

/*
 * 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.geode.cache.query.internal;

import org.apache.geode.cache.query.AmbiguousNameException;
import org.apache.geode.cache.query.FunctionDomainException;
import org.apache.geode.cache.query.NameResolutionException;
import org.apache.geode.cache.query.QueryInvocationTargetException;
import org.apache.geode.cache.query.TypeMismatchException;
import org.apache.geode.pdx.internal.PdxString;

/**
 * Class Description
 *
 * @version $Revision: 1.1 $
 */


public class CompiledLiteral extends AbstractCompiledValue {
  Object _obj;
  PdxString _pdxString;

  public CompiledLiteral(Object obj) {
    _obj = obj;
  }


  @Override
  public int getType() {
    return LITERAL;
  }


  @Override
  public Object evaluate(ExecutionContext context)
      throws FunctionDomainException, TypeMismatchException {
    return _obj;
  }

  /**
   * creates new PdxString from String and caches it
   */
  public PdxString getSavedPdxString() {
    if (_pdxString == null) {
      _pdxString = new PdxString((String) _obj);
    }
    return _pdxString;
  }

  @Override
  public void generateCanonicalizedExpression(StringBuilder clauseBuffer, ExecutionContext context)
      throws AmbiguousNameException, TypeMismatchException {
    if (_obj == null) {
      clauseBuffer.insert(0, "null");
    } else if (_obj instanceof String) {
      clauseBuffer.insert(0, '\'').insert(0, _obj.toString()).insert(0, '\'');
    } else {
      clauseBuffer.insert(0, _obj.toString());
    }
  }

  @Override
  public int getSizeEstimate(ExecutionContext context) throws FunctionDomainException,
      TypeMismatchException, NameResolutionException, QueryInvocationTargetException {
    // The literal could be true or false only in case of Filter
    // Evaluation. Either way it should be evaluated first, Right?
    return 0;
  }

}