程序包 org.hibernate.dialect.function

类 NvlFunction

java.lang.Object

org.hibernate.dialect.function.NvlFunction

所有已实现的接口:

SQLFunction

public class NvlFunction
extends Object
implements SQLFunction

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

作者:

Gavin King

构造器概要

构造器

构造器	说明
NvlFunction()

方法概要

修饰符和类型	方法	说明
Type	getReturnType(Type argumentType, Mapping mapping)	The return type of the function.
boolean	hasArguments()	Does this function have any arguments?
boolean	hasParenthesesIfNoArguments()	If there are no arguments, are parentheses required?
String	render(Type argumentType, List args, SessionFactoryImplementor factory)	Render the function call as SQL fragment.

从类继承的方法 java.lang.Object

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

构造器详细资料

NvlFunction

public NvlFunction()

方法详细资料

hasArguments

public boolean hasArguments()

从接口复制的说明: SQLFunction

Does this function have any arguments?

指定者:

hasArguments 在接口中 SQLFunction

返回:

True if the function expects to have parameters; false otherwise.

hasParenthesesIfNoArguments

public boolean hasParenthesesIfNoArguments()

从接口复制的说明: SQLFunction

If there are no arguments, are parentheses required?

指定者:

hasParenthesesIfNoArguments 在接口中 SQLFunction

返回:

True if a no-arg call of this function requires parentheses.

getReturnType

public Type getReturnType(Type argumentType,
                          Mapping mapping)
                   throws QueryException

从接口复制的说明: 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.

Note, the 'firstArgumentType' parameter should match the one passed into SQLFunction.render(org.hibernate.type.Type, java.util.List, org.hibernate.engine.spi.SessionFactoryImplementor)

指定者:

getReturnType 在接口中 SQLFunction

参数:

argumentType - The type of the first argument

mapping - The mapping source.

返回:

The type to be expected as a return.

抛出:

QueryException - Indicates an issue resolving the return type.

render

public String render(Type argumentType,
                     List args,
                     SessionFactoryImplementor factory)
              throws QueryException

从接口复制的说明: SQLFunction

Render the function call as SQL fragment.

Note, the 'firstArgumentType' parameter should match the one passed into SQLFunction.getReturnType(org.hibernate.type.Type, org.hibernate.engine.spi.Mapping)

指定者:

render 在接口中 SQLFunction

参数:

argumentType - The type of the first argument

args - The function arguments

factory - The SessionFactory

返回:

The rendered function call

抛出:

QueryException - Indicates a problem rendering the function call.