In my web spring application I create an instance with key word new
as following.
In my one of action class, following method exists.
publi
Another solution can be the use of @Component
like this:
@Component("myBean")
public class MyBean{
@Autowired
MyService service;
public void process(){
service.execute(); // this service instance has not initialized by Spring DI :( .service object is null.
}
}
And at your class where process()
is, you can Autowire like this:
@Autowired
MyBean b
public void process(){
b.process();
}
In your case, spring does not recognize MyBean
bean because you are creating it with new
operator. Let spring initialize this bean and then you can have autowired beans accessed inside MyBean
. For e.g.
<bean id="myBean" class="your.package.MyBean"></bean>
Above entry in your application context will create MyBean
in spring container. And using this object you can access the services written inside it.
When you create an object by new, autowire\inject don't work...
as workaround you can try this:
create your template bean of MyBean
<bean id="myBean" class="..." scope="prototype">
<!-- collaborators and configuration for this bean go here -->
</bean>
and create an istance in this way
context.getBean("myBean");
PROTOTYPE : This scopes a single bean definition to have any number of object instances.
If you want to autowire programmatically, you can use:
private @Autowired AutowireCapableBeanFactory beanFactory;
public void process() {
MyBean obj = new MyBean();
beanFactory.autowireBean(obj);
// obj will now have its dependencies autowired.
}
Yes. It is not being set by DI of Spring as the instance you created using new keyword is not being managed by Spring container. Spring will by default inject dependencies only for spring managed instances. So to resolve this problem you can do it by two ways. First is don't use the new
and use @Autowired
on Mybean
instance.
Second is to use @Configurable
on MyBean
class. With the @Configurable
annotation spring will inject dependencies even for objects created through new
keyword. Remember to have AspectJ
jars on your classpath with @configurable
annotation as Spring need them to inject Dependecies.
For the second approach use @Configurable(preConstruction = true)
and add the following dependencies to your pom.xml
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>3.1.1.RELEASE</version>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.6.8</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.6.8</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.6.8</version>
</dependency>
You also need to compile it through AspectJ Compiler so that Byte code generated has the required abilities. You should use the following entries to make sure system using AspectJ Compiler at compile time.
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>aspectj-maven-plugin</artifactId>
<version>1.4</version>
<configuration>
<showWeaveInfo>true</showWeaveInfo>
<source>1.6</source>
<target>1.6</target>
<Xlint>ignore</Xlint>
<complianceLevel>1.6</complianceLevel>
<encoding>UTF-8</encoding>
<verbose>false</verbose>
<aspectLibraries>
<aspectLibrary>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
</aspectLibrary>
</aspectLibraries>
</configuration>
<executions>
<execution>
<goals>
<goal>compile</goal>
<goal>test-compile</goal>
</goals>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>1.6.8</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjtools</artifactId>
<version>1.6.11</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>