Package 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 Details

    • 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 Details

    • 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 Details

    • 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