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 * 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
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package org.apache.ofbiz.entity.datasource;


import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.ofbiz.entity.Delegator;
import org.apache.ofbiz.entity.GenericEntityException;
import org.apache.ofbiz.entity.GenericPK;
import org.apache.ofbiz.entity.GenericValue;
import org.apache.ofbiz.entity.condition.EntityCondition;
import org.apache.ofbiz.entity.model.ModelEntity;
import org.apache.ofbiz.entity.model.ModelField;
import org.apache.ofbiz.entity.model.ModelRelation;
import org.apache.ofbiz.entity.util.EntityFindOptions;
import org.apache.ofbiz.entity.util.EntityListIterator;


/**
 * Generic Entity Helper Class
 *
 */
public interface GenericHelper {

    /** Gets the name of the server configuration that corresponds to this helper
     *@return server configuration name
     */
    public String getHelperName();

    /** Creates a Entity in the form of a GenericValue and write it to the database
     *@return GenericValue instance containing the new instance
     */
    public GenericValue create(GenericValue value) throws GenericEntityException;

    /** Find a Generic Entity by its Primary Key
     *@param primaryKey The primary key to find by.
     *@return The GenericValue corresponding to the primaryKey
     */
    public GenericValue findByPrimaryKey(GenericPK primaryKey) throws GenericEntityException;

    /** Find a Generic Entity by its Primary Key and only returns the values requested by the passed keys (names)
     *@param primaryKey The primary key to find by.
     *@param keys The keys, or names, of the values to retrieve; only these values will be retrieved
     *@return The GenericValue corresponding to the primaryKey
     */
    public GenericValue findByPrimaryKeyPartial(GenericPK primaryKey, Set<String> keys) throws GenericEntityException;

    /** Find a number of Generic Value objects by their Primary Keys, all at once
     *@param primaryKeys A List of primary keys to find by.
     *@return List of GenericValue objects corresponding to the passed primaryKey objects
     */
    public List<GenericValue> findAllByPrimaryKeys(List<GenericPK> primaryKeys) throws GenericEntityException;

    /** Remove a Generic Entity corresponding to the primaryKey
     *@param  primaryKey  The primary key of the entity to remove.
     *@return int representing number of rows effected by this operation
     */
    public int removeByPrimaryKey(GenericPK primaryKey) throws GenericEntityException;

    public List<GenericValue> findByMultiRelation(GenericValue value, ModelRelation modelRelationOne, ModelEntity modelEntityOne,
        ModelRelation modelRelationTwo, ModelEntity modelEntityTwo, List<String> orderBy) throws GenericEntityException;

    /** Finds GenericValues by the conditions specified in the EntityCondition object, the the EntityCondition javadoc for more details.
     *@param modelEntity The ModelEntity of the Entity as defined in the entity XML file
     *@param whereEntityCondition The EntityCondition object that specifies how to constrain this query before any groupings are done (if this is a view entity with group-by aliases)
     *@param havingEntityCondition The EntityCondition object that specifies how to constrain this query after any groupings are done (if this is a view entity with group-by aliases)
     *@param fieldsToSelect The fields of the named entity to get from the database; if empty or null all fields will be retreived
     *@param orderBy The fields of the named entity to order the query by; optionally add a " ASC" for ascending or " DESC" for descending
     *@param findOptions An instance of EntityFindOptions that specifies advanced query options. See the EntityFindOptions JavaDoc for more details.
     *@return EntityListIterator representing the result of the query: NOTE THAT THIS MUST BE CLOSED WHEN YOU ARE
     *      DONE WITH IT (preferably in a finally block), 
     *      AND DON'T LEAVE IT OPEN TOO LONG BECAUSE IT WILL MAINTAIN A DATABASE CONNECTION.
     */
    public EntityListIterator findListIteratorByCondition(Delegator delegator, ModelEntity modelEntity, EntityCondition whereEntityCondition,
        EntityCondition havingEntityCondition, Collection<String> fieldsToSelect, List<String> orderBy, EntityFindOptions findOptions)
        throws GenericEntityException;

    public long findCountByCondition(Delegator delegator, ModelEntity modelEntity, EntityCondition whereEntityCondition,
            EntityCondition havingEntityCondition, EntityFindOptions findOptions) throws GenericEntityException;

    long findCountByCondition(Delegator delegator, ModelEntity modelEntity, EntityCondition whereEntityCondition,
                                     EntityCondition havingEntityCondition, List<ModelField> selectFields,
                                     EntityFindOptions findOptions) throws GenericEntityException;

    /** Removes/deletes Generic Entity records found by all the specified condition
     *@param modelEntity The ModelEntity of the Entity as defined in the entity XML file
     *@param condition The condition that restricts the list of removed values
     *@return int representing number of rows effected by this operation
     */
    public int removeByCondition(Delegator delegator, ModelEntity modelEntity, EntityCondition condition) throws GenericEntityException;

    /** Stores a group of values in a single query
     *@param modelEntity The ModelEntity of the Entity as defined in the entity XML file
     *@param fieldsToSet The fields of the named entity to set in the database
     *@param condition The condition that restricts the list of updated values
     *@return int representing number of rows effected by this operation
     *@throws GenericEntityException
     */
    public int storeByCondition(Delegator delegator, ModelEntity modelEntity, Map<String, ? extends Object> fieldsToSet, EntityCondition condition) throws GenericEntityException;

    /** Store the Entity from the GenericValue to the persistent store
     *@param value GenericValue instance containing the entity
     *@return int representing number of rows effected by this operation
     */
    public int store(GenericValue value) throws GenericEntityException;

    /** Check the datasource to make sure the entity definitions are correct, optionally adding missing entities or fields on the server
     *@param modelEntities Map of entityName names and ModelEntity values
     *@param messages List to put any result messages in
     *@param addMissing Flag indicating whether or not to add missing entities and fields on the server
     */
    public void checkDataSource(Map<String, ModelEntity> modelEntities, List<String> messages, boolean addMissing) throws GenericEntityException;
}
