org.hibernate.dialect.function
Class NvlFunction

java.lang.Object
  extended by org.hibernate.dialect.function.NvlFunction
All Implemented Interfaces:
SQLFunction

public class NvlFunction
extends Object
implements SQLFunction

Emulation of coalesce() on Oracle, using multiple nvl() calls

Author:
Gavin King

Constructor Summary
NvlFunction()
           
 
Method Summary
 Type getReturnType(Type columnType, Mapping mapping)
          The return type of the function.
 boolean hasArguments()
          Does this function have any arguments?
 boolean hasParenthesesIfNoArguments()
          If there are no arguments, are parens required?
 String render(List args, SessionFactoryImplementor factory)
          Render the function call as SQL fragment.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NvlFunction

public NvlFunction()
Method Detail

getReturnType

public Type getReturnType(Type columnType,
                          Mapping mapping)
                   throws QueryException
Description copied from interface: SQLFunction
The return type of the function. May be either a concrete type which is preset, or variable depending upon the type of the first function argument.

Specified by:
getReturnType in interface SQLFunction
Parameters:
columnType - the type of the first argument
mapping - The mapping source.
Returns:
The type to be expected as a return.
Throws:
QueryException - Indicates an issue resolving the return type.

hasArguments

public boolean hasArguments()
Description copied from interface: SQLFunction
Does this function have any arguments?

Specified by:
hasArguments in interface SQLFunction
Returns:
True if the function expects to have parameters; false otherwise.

hasParenthesesIfNoArguments

public boolean hasParenthesesIfNoArguments()
Description copied from interface: SQLFunction
If there are no arguments, are parens required?

Specified by:
hasParenthesesIfNoArguments in interface SQLFunction
Returns:
True if a no-arg call of this function requires parentheses.

render

public String render(List args,
                     SessionFactoryImplementor factory)
              throws QueryException
Description copied from interface: SQLFunction
Render the function call as SQL fragment.

Specified by:
render in interface SQLFunction
Parameters:
args - The function arguments
factory - The SessionFactory
Returns:
The rendered function call
Throws:
QueryException - Indicates a problem rendering the function call.