使用工厂方法的Spring autowire对象(Spring autowire object using factory method)

使用工厂方法的Spring autowire对象(Spring autowire object using factory method)

我试图弄清楚如何将这个java代码更改为spring

private MyObject myObject = MyObjectFactory.getService();

在我的Foo.java课程中

@Autowired private MyObject myObject;

在春天的xml中，我有：

<bean id="MyObject" class="path.to.MyObjectFactory" factory-method="getService"></bean> <bean id="Foo" class="path.to.Foo"> <property name="myObject" ref="MyObject"/> </bean>

错误是

No matching bean of type [path.to.MyObject] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency.

I'm trying to figure out how to change this java code into spring

private MyObject myObject = MyObjectFactory.getService();

In my Foo.java class I have

@Autowired private MyObject myObject;

In the spring xml, I have:

<bean id="MyObject" class="path.to.MyObjectFactory" factory-method="getService"></bean> <bean id="Foo" class="path.to.Foo"> <property name="myObject" ref="MyObject"/> </bean>

The error is

No matching bean of type [path.to.MyObject] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency.

最满意答案

您尝试将类型为MyObjectFactory的对象注入path.to.Foo，其中需要MyObject类型的对象。 请改变你的代码：

富：

public class Foo { private MyObject myObject; public void setMyObject(MyObject value) { myObject=value;} }

MyObjectFactory：

public class MyObjectFactory { public MyObject getService() { return new MyObject(); } }

spring xml：

<bean class="MyObjectFactory" id="factory" /> <bean id="myObject" factory-bean="factory" factory-method="getService" scope="prototype" /> <bean id="Foo" class="path.to.Foo"> <property name="myObject" ref="MyObject"/> </bean>

顺便说一下，@ @Autowired和<property ...>在你的情况下表达同样的事情，所以你可以把这一个或另一个留下来。

更新：

看看这里有关春季工厂豆的更多信息。

我假设你不想要单身，这就是我添加scope="prototype" 。 如果您的MyObject实例假设是单例，请将其删除。

you try to inject a object of type MyObjectFactory into path.to.Foo, where a object of type MyObject is expected. please change your code like this:

Foo:

public class Foo { private MyObject myObject; public void setMyObject(MyObject value) { myObject=value;} }

MyObjectFactory:

public class MyObjectFactory { public MyObject getService() { return new MyObject(); } }

spring xml:

<bean class="MyObjectFactory" id="factory" /> <bean id="myObject" factory-bean="factory" factory-method="getService" scope="prototype" /> <bean id="Foo" class="path.to.Foo"> <property name="myObject" ref="MyObject"/> </bean>

By the way, @Autowired and <property ...> express the same thing in your case, so you could leave the one or the other out.

UPDATE:

take a look here for more information factory beans in spring.

i assumed you do not want a singleton, that is why i added scope="prototype". remove it, if your instance of MyObject suppose to be a singleton.