com.xj.anylogic.engine.connectivity
Class Query

java.lang.Object
  com.xj.anylogic.engine.connectivity.Query

All Implemented Interfaces:

java.io.Serializable

public class Query
extends java.lang.Object

Query object for database connectivity
Works in 2 modes:

• Returns ResultSet object (see execute()) which can be iterated to retrieve result values
• Maps rows of database resulting table to the fields of newly created elements in collection or new ActiveObjects in the Replicated Active Object element (see executeAndMap())

This object is only available in the AnyLogic Professional

Author:

XJ Technologies Company Ltd. www.anylogic.com

See Also:

Serialized Form

Constructor Summary

Query(java.lang.String name, Database database, boolean selectFromTable, java.lang.String tableNameOrQueryText)
Creates new Query for work only with execute() method

Query(java.lang.String name, Database database, boolean selectFromTable, java.lang.String tableNameOrQueryText, java.lang.String[][] mapping)
Creates new Query for work in the Mapping mode (executeAndMap() method)
Note the execute() method is still available for this object

Method Summary

java.lang.Object	createNewRowElementInstance() Extension-point for element creation In the Mapping mode, this method should be overridden to create specifical element and return it
void	destroy() Releases resources acquired by this object Also destroys all not destroyed contributors associated with this object Doest nothing if object is already destroyed
ResultSet	execute() Executes query in the database and returns single ResultSet If any error occurs, throws RuntimeException Connects Database if it is not connected.
int	executeAndMap() This method fills underlying collection or Replicated Active Object (created Active Objects are started automatically) with elements created from rows of database Query result This method works only in the Mapping mode
int	executeAndMap(boolean startActiveObjects) This method fills underlying collection or Replicated Active Object with elements created from rows of database Query result This method works only in the Mapping mode
java.lang.String	getName() Returns the name of this object
void	registerNewRowElement(java.lang.Object element, boolean startActiveObjects) Extension-point for element creation In the Mapping mode, this method should be overridden to start given element (previously created by createNewRowElementInstance() and parametrized) add it to the underlying collection and return it
java.lang.String	toString()

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Query

public Query(java.lang.String name,
             Database database,
             boolean selectFromTable,
             java.lang.String tableNameOrQueryText)

Creates new Query for work only with execute() method

Parameters:

name - object name (decoration purpose)

database -

selectFromTable -

tableNameOrQueryText -

Query

public Query(java.lang.String name,
             Database database,
             boolean selectFromTable,
             java.lang.String tableNameOrQueryText,
             java.lang.String[][] mapping)

Creates new Query for work in the Mapping mode (executeAndMap() method)
Note the execute() method is still available for this object

Parameters:

name - object name (decoration purpose)

database - database to connect to

selectFromTable - flag indicating what value is contained in parameter tableNameOrQueryText

tableNameOrQueryText -

• the table name to select data from, - if selectFromTable is true
• SQL query text, otherwise

mapping - mappings array with dimensions N x 2 like:

 new String[][] { { "fieldName0", "columnLabel0" },
                { "fieldName1", "columnLabel1" },
 // ...
 }
 

where

• fieldName is name of field in the created collection element or ActiveObject
• columnLabel is column's title which is used in printouts and displays. This title is usually specified by the SQL AS clause. If a SQL AS is not specified, the table column name is assumed

Method Detail

createNewRowElementInstance

public java.lang.Object createNewRowElementInstance()

Extension-point for element creation
In the Mapping mode, this method should be overridden to create specifical element and return it

Returns:

new element instance created for each row

registerNewRowElement

public void registerNewRowElement(java.lang.Object element,
                                  boolean startActiveObjects)

Extension-point for element creation
In the Mapping mode, this method should be overridden to start given element (previously created by createNewRowElementInstance() and parametrized) add it to the underlying collection and return it

Parameters:

startActiveObjects - defines either created Active Objects are started or not
overridden method should call start() method on active object only if this parameter is true

execute

public final ResultSet execute()

Executes query in the database and returns single ResultSet
If any error occurs, throws RuntimeException
Connects Database if it is not connected. After this method call Database remains connected.

Returns:

new ResultSet object; never null
Please call ResultSet.close() method after all needed operations are completed

executeAndMap

public final int executeAndMap()

This method fills underlying collection or Replicated Active Object (created Active Objects are started automatically) with elements created from rows of database Query result
This method works only in the Mapping mode

Returns:

number of created objects

executeAndMap

public final int executeAndMap(boolean startActiveObjects)

This method fills underlying collection or Replicated Active Object with elements created from rows of database Query result
This method works only in the Mapping mode

Parameters:

startActiveObjects - defines either created Active Objects are started or not

Returns:

number of created objects

toString

public java.lang.String toString()

getName

public final java.lang.String getName()

Returns the name of this object

Returns:

the name of this object

destroy

public final void destroy()

Releases resources acquired by this object
Also destroys all not destroyed contributors associated with this object

Doest nothing if object is already destroyed