org.springframework.jdbc.object
Class SqlFunction

org.springframework.jdbc.object.RdbmsOperation
  |
  +--org.springframework.jdbc.object.SqlOperation
        |
        +--org.springframework.jdbc.object.SqlQuery
              |
              +--org.springframework.jdbc.object.MappingSqlQueryWithParameters
                    |
                    +--org.springframework.jdbc.object.MappingSqlQuery
                          |
                          +--org.springframework.jdbc.object.SqlFunction

public class SqlFunction

extends MappingSqlQuery

SQL "function" wrapper for a query that returns a single row of results. The default behavior is to return an int, but that can be overridden by using the methods with an extra return type parameter. Intended to use to call SQL functions that return a single result using a query like "select user()" or "select sysdate from dual". It is not intended for calling more complex stored functions or for using a callableStatement to invoke a stored procedure or stored function. Use StoredProcedure or SqlCall for this type of processing.

This is a concrete class, which there is normally no need to subclass. Code using this package can create an object of this type, declaring SQL and parameters, and then invoke the appropriate run() method repeatedly to execute the function.

Like all RdbmsOperation objects, SqlFunction objects are threadsafe.

Author:

Rod Johnson, Isabelle Muszynski, Jean-Pierre Pawlak

Version: $Id: SqlFunction.java,v 1.5 2003/12/15 13:52:02 trisberg Exp $

See Also: org.springframework.jdbc.object.StoredProcedure History

Methods inherited from class org.springframework.jdbc.object.RdbmsOperation

afterPropertiesSet, compile, declareParameter, getSql, isCompiled, setDataSource, setJdbcTemplate, setSql, setTypes

Constructor Detail

SqlFunction

public SqlFunction()

Constructor to allow use as a JavaBean. A DataSource, SQL and any parameters must be supplied before invoking the compile() method and using this object.

public SqlFunction(DataSource ds, String sql, int[] types)

Create a new SQLFunction object with SQL and parameters.

Parameters:

ds - DataSource to obtain connections from

sql - SQL to execute

types - SQL types of the parameters, as defined in the java.sql.Types class

public SqlFunction(DataSource ds, String sql, int[] types, int retType)
              throws org.springframework.dao.InvalidDataAccessApiUsageException

Create a new SQLFunction object with SQL, parameters and a return type

Parameters:

ds - DataSource to obtain connections from

sql - SQL to execute

types - SQL types of the parameters, as defined in the java.sql.Types class

retType - SQL type of the return value, as defined in the java.sql.Types class

Throws:

InvalidDataAccessApiUsageException - is thrown if the return type is not numeric or char

public SqlFunction(DataSource ds, String sql)

Create a new SQLFunction object with SQL, but without parameters. Must add parameters or settle with none.

Parameters:

ds - DataSource to obtain connections from

sql - SQL to execute

public SqlFunction(DataSource ds, String sql, int retType)

Create a new SQLFunction object with SQL and return type, but without parameters. Must add parameters or settle with none.

Parameters:

ds - DataSource to obtain connections from

sql - SQL to execute

retType - SQL type of the return value, as defined in the java.sql.Types class

public int run()

Convenient method to run the function without arguments.

Returns: the value of the function

public int run(int p)

Convenient method to run the function with a single int argument.

Parameters:

p - single int argument

Returns: the value of the function

public int run(Object[] args)

Analogous to the SqlQuery.execute([]) method. This is a generic method to execute a query, taken a number of arguments.

Parameters:

args - array of arguments. These will be objects or object wrapper types for primitives.

Returns: the value of the function

public Object runGeneric()

Convenient method to run the function without arguments, returning the value as an object

Returns: the value of the function

public Object runGeneric(int p)

Convenient method to run the function with a single int argument.

Parameters:

p - single int argument

Returns: the value of the function as an Object

public Object runGeneric(Object[] args)

Analogous to the SqlQuery.execute([]) method. This is a generic method to execute a query, taken a number of arguments.

Parameters:

args - array of arguments. These will be objects or object wrapper types for primitives.

Returns: the value of the function, as an Object