org.sqlproc.engine.impl

Class SqlMappingResult

java.lang.Object

org.sqlproc.engine.impl.SqlMappingResult

public class SqlMappingResult
extends Object

Holds the results of an explicit and an implicit mapping rules merging. In the case of explicit mapping rule the grammar itself is defined in SqlMapping.g. In the case of implicit mapping rule the grammar itself is defined in SqlStatement.g. The internal mapping rule is a dynamic one, and it's finalized in the process of the final ANSI SQL query generation. For the purpose of correct left join handling, the identities are identified. They are used to prevent the repeated rows in the output result set. This is used for the associations (one-to-one, one-to-many and many-to-many). The main runtime contracts are setQueryResultMapping(Class, Map, SqlQuery) and setQueryResultData(Object, Object[], Map, Map).

Author:

Vladimir Hudec

Field Summary

Fields

Modifier and Type	Field and Description
private SqlProcessContext	ctx The crate for all input parameters and the context of processing.
(package private) Map<String,SqlMappingIdentity>	identities The collection of identities related to all output columns.
(package private) List<Integer>	identitiesIndexes The list of identities indexes in the list of output values.
(package private) org.slf4j.Logger	logger The internal slf4j logger.
(package private) Integer	mainIdentityIndex The main identity index in the list of output values.
private Map<String,SqlMappingItem>	mappings All sub-elements based on ANTLR grammar defined in SqlMapping.g or SqlStatement.g.

Constructor Summary

Constructors

Constructor and Description
SqlMappingResult(SqlProcessContext ctx, SqlMappingRule mapping, Map<String,SqlMappingItem> outputMappings) Creates a new instance.

Method Summary

Modifier and Type	Method and Description
(package private) void	addMapping(SqlMappingItem item) Adds a new mapping rule item in the merging process.
(package private) void	calculateIdentities() Calculates all identities related information.
Object	getFunctionResultData(Map<String,Object> result) Devoted to function output value conversion.
List<Integer>	getIdentitiesIndexes() Return the list of identities indexes in the list of output values
Map<String,Object>	getIds() Construct the empty structure used for the instances of all already used identities together with the related result instances based on identities indices.
Integer	getMainIdentityIndex() Returns the main identity index in the list of output values.
SqlRuntimeContext	getRuntimeContext() Returns the public runtime context
private void	merge(SqlMappingRule mapping, Map<String,SqlMappingItem> outputMappings) Merge mapping rule for one META SQL query based on SqlMapping.g and SqlStatement.g.
void	setQueryResultData(Object resultInstance, Object[] resultValues, Map<String,Object> ids, Map<String,Class<?>> moreResultClasses) Fills the instance of the result class with output values from the SQL query execution.
void	setQueryResultMapping(Class<?> resultClass, Map<String,Class<?>> moreResultClasses, SqlQuery query) Declares a scalar query results for all mapping rule items.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

logger

final org.slf4j.Logger logger

The internal slf4j logger.

ctx

private SqlProcessContext ctx

The crate for all input parameters and the context of processing.

mappings

private Map<String,SqlMappingItem> mappings

All sub-elements based on ANTLR grammar defined in SqlMapping.g or SqlStatement.g. Every sub-element is one Mapping item.

identities

Map<String,SqlMappingIdentity> identities

The collection of identities related to all output columns.

identitiesIndexes

List<Integer> identitiesIndexes

The list of identities indexes in the list of output values.

mainIdentityIndex

Integer mainIdentityIndex

The main identity index in the list of output values. The main identity is related to the top level result class.

Constructor Detail

SqlMappingResult

SqlMappingResult(SqlProcessContext ctx,
                 SqlMappingRule mapping,
                 Map<String,SqlMappingItem> outputMappings)

Creates a new instance. This instances is based on the merging of an explicit and an implicit mapping rules.

Parameters:

ctx - the crate for all input parameters and the context of processing

mapping - mapping rule based on SqlMapping.g or the empty one

outputMappings - mapping rule items based on SqlStatement.g

Method Detail

getMainIdentityIndex

public Integer getMainIdentityIndex()

Returns the main identity index in the list of output values. The main identity is related to the top level result class.

Returns:

the main identity index in the list of output values

getIdentitiesIndexes

public List<Integer> getIdentitiesIndexes()

Return the list of identities indexes in the list of output values

Returns:

the list of identities indexes in the list of output values

getRuntimeContext

public SqlRuntimeContext getRuntimeContext()

Returns the public runtime context

Returns:

the public runtime context

addMapping

void addMapping(SqlMappingItem item)

Adds a new mapping rule item in the merging process.

Parameters:

item - a new mapping rule item

calculateIdentities

void calculateIdentities()

Calculates all identities related information. They are used to prevent the repeated rows in the output result set. This is used for the associations (one-to-one, one-to-many and many-to-many).

setQueryResultMapping

public void setQueryResultMapping(Class<?> resultClass,
                                  Map<String,Class<?>> moreResultClasses,
                                  SqlQuery query)
                           throws SqlRuntimeException

Declares a scalar query results for all mapping rule items.

Parameters:

resultClass - the class used for the return values

moreResultClasses - more result classes used for the return values, like the collections classes or the collections items

query - the SQL Engine query, an adapter or proxy to the internal JDBC or ORM staff

Throws:

SqlRuntimeException - in the case of any problem with output values preparation

setQueryResultData

public void setQueryResultData(Object resultInstance,
                               Object[] resultValues,
                               Map<String,Object> ids,
                               Map<String,Class<?>> moreResultClasses)
                        throws SqlRuntimeException

Fills the instance of the result class with output values from the SQL query execution.

Parameters:

resultInstance - the instance of the result class

resultValues - the query execution output values

ids - the instances of all already used identities together with the related result instances based on identities indices

moreResultClasses - more result classes used for the return values, like the collections classes or the collections items

Throws:

SqlRuntimeException - in the case of any problem with output values handling

merge

private void merge(SqlMappingRule mapping,
                   Map<String,SqlMappingItem> outputMappings)

Merge mapping rule for one META SQL query based on SqlMapping.g and SqlStatement.g. The external mapping rule has the higher priority. The internal mapping rule holds the list of real output values.

Parameters:

mapping - mapping rule based on SqlMapping.g or the empty one

outputMappings - mapping rule items based on SqlStatement.g

getIds

public Map<String,Object> getIds()

Construct the empty structure used for the instances of all already used identities together with the related result instances based on identities indices.

Returns:

the empty structure used for the instances of all already used identities together with the related result instances based on identities indices

getFunctionResultData

public Object getFunctionResultData(Map<String,Object> result)

Devoted to function output value conversion.

Parameters:

result - the JDBC output value

Returns:

the output value after possible conversion