类 MethodInvokingFactoryBean
- java.lang.Object
- org.springframework.util.MethodInvoker
- org.springframework.beans.support.ArgumentConvertingMethodInvoker
- org.springframework.beans.factory.config.MethodInvokingBean
- org.springframework.beans.factory.config.MethodInvokingFactoryBean
- 所有已实现的接口:
Aware
,BeanClassLoaderAware
,BeanFactoryAware
,FactoryBean<Object>
,InitializingBean
public class MethodInvokingFactoryBean extends MethodInvokingBean implements FactoryBean<Object>
FactoryBean
which returns a value which is the result of a static or instance method invocation. For most use cases it is better to just use the container's built-in factory method support for the same purpose, since that is smarter at converting arguments. This factory bean is still useful though when you need to call a method which doesn't return any value (for example, a static class method to force some sort of initialization to happen). This use case is not supported by factory methods, since a return value is needed to obtain the bean instance.Note that as it is expected to be used mostly for accessing factory methods, this factory by default operates in a singleton fashion. The first request to
getObject()
by the owning bean factory will cause a method invocation, whose return value will be cached for subsequent requests. An internalsingleton
property may be set to "false", to cause this factory to invoke the target method each time it is asked for an object.NOTE: If your target method does not produce a result to expose, consider
MethodInvokingBean
instead, which avoids the type determination and lifecycle limitations that thisMethodInvokingFactoryBean
comes with.This invoker supports any kind of target method. A static method may be specified by setting the
targetMethod
property to a String representing the static method name, withtargetClass
specifying the Class that the static method is defined on. Alternatively, a target instance method may be specified, by setting thetargetObject
property as the target object, and thetargetMethod
property as the name of the method to call on that target object. Arguments for the method invocation may be specified by setting thearguments
property.This class depends on
afterPropertiesSet()
being called once all properties have been set, as per the InitializingBean contract.An example (in an XML based bean factory definition) of a bean definition which uses this class to call a static factory method:
<bean id="myObject" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean"> <property name="staticMethod" value="com.whatever.MyClassFactory.getInstance"/> </bean>
An example of calling a static method then an instance method to get at a Java system property. Somewhat verbose, but it works.
<bean id="sysProps" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean"> <property name="targetClass" value="java.lang.System"/> <property name="targetMethod" value="getProperties"/> </bean> <bean id="javaVersion" class="org.springframework.beans.factory.config.MethodInvokingFactoryBean"> <property name="targetObject" ref="sysProps"/> <property name="targetMethod" value="getProperty"/> <property name="arguments" value="java.version"/> </bean>
- 从以下版本开始:
- 21.11.2003
- 作者:
- Colin Sampaleanu, Juergen Hoeller
- 另请参阅:
MethodInvokingBean
,MethodInvoker
字段概要
从类继承的字段 org.springframework.util.MethodInvoker
targetClass
从接口继承的字段 org.springframework.beans.factory.FactoryBean
OBJECT_TYPE_ATTRIBUTE
构造器概要
构造器 构造器 说明 MethodInvokingFactoryBean()
方法概要
所有方法 实例方法 具体方法 修饰符和类型 方法 说明 void
afterPropertiesSet()
Invoked by the containingBeanFactory
after it has set all bean properties and satisfiedBeanFactoryAware
,ApplicationContextAware
etc.Object
getObject()
Returns the same value each time if the singleton property is set to "true", otherwise returns the value returned from invoking the specified method on the fly.Class<?>
getObjectType()
Return the type of object that this FactoryBean creates, ornull
if not known in advance.boolean
isSingleton()
Is the object managed by this factory a singleton?void
setSingleton(boolean singleton)
Set if a singleton should be created, or a new object on eachgetObject()
request otherwise.从类继承的方法 org.springframework.beans.factory.config.MethodInvokingBean
getDefaultTypeConverter, invokeWithTargetException, resolveClassName, setBeanClassLoader, setBeanFactory
从类继承的方法 org.springframework.beans.support.ArgumentConvertingMethodInvoker
doFindMatchingMethod, findMatchingMethod, getTypeConverter, registerCustomEditor, setTypeConverter
从类继承的方法 org.springframework.util.MethodInvoker
getArguments, getPreparedMethod, getTargetClass, getTargetMethod, getTargetObject, getTypeDifferenceWeight, invoke, isPrepared, prepare, setArguments, setStaticMethod, setTargetClass, setTargetMethod, setTargetObject
构造器详细资料
MethodInvokingFactoryBean
public MethodInvokingFactoryBean()
方法详细资料
setSingleton
public void setSingleton(boolean singleton)
Set if a singleton should be created, or a new object on eachgetObject()
request otherwise. Default is "true".
afterPropertiesSet
public void afterPropertiesSet() throws Exception
从接口复制的说明:InitializingBean
Invoked by the containingBeanFactory
after it has set all bean properties and satisfiedBeanFactoryAware
,ApplicationContextAware
etc.This method allows the bean instance to perform validation of its overall configuration and final initialization when all bean properties have been set.
- 指定者:
afterPropertiesSet
在接口中InitializingBean
- 覆盖:
afterPropertiesSet
在类中MethodInvokingBean
- 抛出:
Exception
- in the event of misconfiguration (such as failure to set an essential property) or if initialization fails for any other reason
getObject
@Nullable public Object getObject() throws Exception
Returns the same value each time if the singleton property is set to "true", otherwise returns the value returned from invoking the specified method on the fly.- 指定者:
getObject
在接口中FactoryBean<Object>
- 返回:
- an instance of the bean (can be
null
) - 抛出:
Exception
- in case of creation errors- 另请参阅:
FactoryBeanNotInitializedException
getObjectType
public Class<?> getObjectType()
Return the type of object that this FactoryBean creates, ornull
if not known in advance.- 指定者:
getObjectType
在接口中FactoryBean<Object>
- 返回:
- the type of object that this FactoryBean creates, or
null
if not known at the time of the call - 另请参阅:
ListableBeanFactory.getBeansOfType(java.lang.Class<T>)
isSingleton
public boolean isSingleton()
从接口复制的说明:FactoryBean
Is the object managed by this factory a singleton? That is, willFactoryBean.getObject()
always return the same object (a reference that can be cached)?NOTE: If a FactoryBean indicates to hold a singleton object, the object returned from
getObject()
might get cached by the owning BeanFactory. Hence, do not returntrue
unless the FactoryBean always exposes the same reference.The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.
NOTE: This method returning
false
does not necessarily indicate that returned objects are independent instances. An implementation of the extendedSmartFactoryBean
interface may explicitly indicate independent instances through itsSmartFactoryBean.isPrototype()
method. PlainFactoryBean
implementations which do not implement this extended interface are simply assumed to always return independent instances if theisSingleton()
implementation returnsfalse
.The default implementation returns
true
, since aFactoryBean
typically manages a singleton instance.- 指定者:
isSingleton
在接口中FactoryBean<Object>
- 返回:
- whether the exposed object is a singleton
- 另请参阅:
FactoryBean.getObject()
,SmartFactoryBean.isPrototype()