com.orientechnologies.orient.core.sql.operator.OQueryOperator Maven / Gradle / Ivy

/*
  *
  *  *  Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
  *  *
  *  *  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.
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package com.orientechnologies.orient.core.sql.operator;

import java.util.List;

import com.orientechnologies.common.profiler.OProfilerMBean;
import com.orientechnologies.orient.core.Orient;
import com.orientechnologies.orient.core.command.OCommandContext;
import com.orientechnologies.orient.core.db.record.OIdentifiable;
import com.orientechnologies.orient.core.id.ORID;
import com.orientechnologies.orient.core.index.OIndex;
import com.orientechnologies.orient.core.index.OIndexCursor;
import com.orientechnologies.orient.core.index.OIndexDefinition;
import com.orientechnologies.orient.core.metadata.schema.OClass;
import com.orientechnologies.orient.core.record.impl.ODocument;
import com.orientechnologies.orient.core.sql.OIndexSearchResult;
import com.orientechnologies.orient.core.sql.filter.OSQLFilterCondition;
import com.orientechnologies.orient.core.sql.operator.math.*;

/**
 * Query Operators. Remember to handle the operator in OQueryItemCondition.
 * 
 * @author Luca Garulli
 */
public abstract class OQueryOperator {

  public static enum ORDER {
    /**
     * Used when order compared to other operator can not be evaluated or has no consequences.
     */
    UNKNOWNED,
    /**
     * Used when this operator must be before the other one
     */
    BEFORE,
    /**
     * Used when this operator must be after the other one
     */
    AFTER,
    /**
     * Used when this operator is equal the other one
     */
    EQUAL
  }

  /**
   * Default operator order. can be used by additional operator to locate themself relatively to default ones.
   * 
   * WARNING: ORDER IS IMPORTANT TO AVOID SUB-STRING LIKE "IS" and AND "INSTANCEOF": INSTANCEOF MUST BE PLACED BEFORE! AND ALSO FOR
   * PERFORMANCE (MOST USED BEFORE)
   */
  protected static final Class[] DEFAULT_OPERATORS_ORDER = { OQueryOperatorEquals.class, OQueryOperatorAnd.class,
      OQueryOperatorOr.class, OQueryOperatorNotEquals.class, OQueryOperatorNot.class, OQueryOperatorMinorEquals.class,
      OQueryOperatorMinor.class, OQueryOperatorMajorEquals.class, OQueryOperatorContainsAll.class, OQueryOperatorMajor.class,
      OQueryOperatorLike.class, OQueryOperatorMatches.class, OQueryOperatorInstanceof.class, OQueryOperatorIs.class,
      OQueryOperatorIn.class, OQueryOperatorContainsKey.class, OQueryOperatorContainsValue.class, OQueryOperatorContainsText.class,
      OQueryOperatorContains.class, OQueryOperatorTraverse.class, OQueryOperatorBetween.class, OQueryOperatorPlus.class,
      OQueryOperatorMinus.class, OQueryOperatorMultiply.class, OQueryOperatorDivide.class, OQueryOperatorMod.class };

  public final String               keyword;
  public final int                  precedence;
  public final int                  expectedRightWords;
  public final boolean              unary;
  public final boolean              expectsParameters;

  protected OQueryOperator(final String iKeyword, final int iPrecedence, final boolean iUnary) {
    this(iKeyword, iPrecedence, iUnary, 1, false);
  }

  protected OQueryOperator(final String iKeyword, final int iPrecedence, final boolean iUnary, final int iExpectedRightWords) {
    this(iKeyword, iPrecedence, iUnary, iExpectedRightWords, false);
  }

  protected OQueryOperator(final String iKeyword, final int iPrecedence, final boolean iUnary, final int iExpectedRightWords,
      final boolean iExpectsParameters) {
    keyword = iKeyword;
    precedence = iPrecedence;
    unary = iUnary;
    expectedRightWords = iExpectedRightWords;
    expectsParameters = iExpectsParameters;
  }

  public abstract Object evaluateRecord(final OIdentifiable iRecord, ODocument iCurrentResult,
      final OSQLFilterCondition iCondition, final Object iLeft, final Object iRight, OCommandContext iContext);

  /**
   * Returns hint how index can be used to calculate result of operator execution.
   * 
   * @param iLeft
   *          Value of left query parameter.
   * @param iRight
   *          Value of right query parameter.
   * @return Hint how index can be used to calculate result of operator execution.
   */
  public abstract OIndexReuseType getIndexReuseType(Object iLeft, Object iRight);

  public OIndexSearchResult getOIndexSearchResult(OClass iSchemaClass, OSQLFilterCondition iCondition,
      List iIndexSearchResults, OCommandContext context) {

    return null;
  }

  /**
   * Performs index query and returns index cursor which presents subset of index data which corresponds to result of execution of
   * given operator.
   * 
   * 

   * Query that should be executed can be presented like: [[property0 = keyParam0] and [property1 = keyParam1] and] propertyN
   * operator keyParamN.
   * 

   * It is supped that index which passed in as parameter is used to index properties listed above and responsibility of given
   * method execute query using given parameters.
   * 

   * Multiple parameters are passed in to implement composite indexes support.
   * 
   * 
   * @param iContext
   * @param index
   *          Instance of index that will be used to calculate result of operator execution.
   * @param keyParams
   *          Parameters of query is used to calculate query result.
   * @param ascSortOrder
   *          Data returned by cursors should be sorted in ascending or descending order.
   * @return Cursor instance if index can be used to evaluate result of execution of given operator and null otherwise.
   */
  public OIndexCursor executeIndexQuery(OCommandContext iContext, OIndex index, final List