org.sqlproc.engine.impl

Class SqlMappingRule

java.lang.Object

org.sqlproc.engine.impl.SqlMappingRule

public class SqlMappingRule
extends Object

The precompiled mapping entity for one external META SQL mapping rule. Instances of this class are created by the ANTLR parser. The grammar itself is defined in SqlMapping.g. The main runtime contracts is merge(SqlMappingRule, SqlProcessResult).

Schematically:

 SqlMappingRule = SqlMappingItem+
     SqlMappingItem = dbName$sqlType$javaName^(value(=value2)?)*.javaName...
 

Author:

Vladimir Hudec

Field Summary

Fields

Modifier and Type	Field and Description
protected static org.slf4j.Logger	logger The internal slf4j logger.
private Map<String,SqlMappingItem>	mappings All sub-elements based on ANTLR grammar defined in SqlMapping.g.

Constructor Summary

Constructors

Constructor and Description
SqlMappingRule() Creates a new instance.

Method Summary

Methods

Modifier and Type	Method and Description
(package private) void	addMapping(SqlMappingItem item) Adds a new Mapping item, which is a mapping rule for one column.
static SqlMappingRule	getInstance(String name, String mappingStatement, SqlTypeFactory typeFactory) Simple factory method (design pattern).
(package private) Map<String,SqlMappingItem>	getMappings() Returns a collection of all mapping items in this mapping rule.
static SqlMappingResult	merge(SqlMappingRule mapping, SqlProcessResult processResult) Merge mapping rule for one META SQL query based on SqlMapping.g and SqlStatement.g.

Methods inherited from class java.lang.Object

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

Field Detail

logger

protected static org.slf4j.Logger logger

The internal slf4j logger.

mappings

private Map<String,SqlMappingItem> mappings

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

Constructor Detail

SqlMappingRule

public SqlMappingRule()

Creates a new instance. It's used from inside ANTLR parser.

Method Detail

getInstance

public static SqlMappingRule getInstance(String name,
                         String mappingStatement,
                         SqlTypeFactory typeFactory)
                                  throws SqlEngineException

Simple factory method (design pattern). The new instance of precompiled mapping rule is created from the String input by the ANTLR parser.

Parameters:

name - the name of this mapping rule

mappingStatement - String representation of mapping rule

typeFactory - the factory for the META types construction

Returns:

the new instance of precompiled mapping rule

Throws:

SqlEngineException - in the case of ANTRL parsing exception

addMapping

void addMapping(SqlMappingItem item)

Adds a new Mapping item, which is a mapping rule for one column.

Parameters:

item - the mapping item

getMappings

Map<String,SqlMappingItem> getMappings()

Returns a collection of all mapping items in this mapping rule.

Returns:

the collection of all mapping items

merge

public static SqlMappingResult merge(SqlMappingRule mapping,
                     SqlProcessResult processResult)

Merge mapping rule for one META SQL query based on SqlMapping.g and SqlStatement.g. The mapping rule based on SqlMapping.g has the higher priority compared to mapping rule based on SqlStatement.g. The mapping rule based on SqlStatement.g obtains a list of real output values.

Parameters:

mapping - the mapping rule based on SqlMapping.g

processResult - contains a mapping rule based on SqlStatement.g

Returns:

the crate for output mapping rule and database row identities