I have a resource file created in my project. I want to inject values from resource file into spring bean. i defined the place holder for resource file in the applicacationContext.xml.
<context:property-placeholder location="file:///${MRAPOR_PROPPATH}mRapor.properties" />
I can inject values to beans which is declared in the applicationContext.xml like :
<bean
id="dataSource"
class="org.springframework.jndi.JndiObjectFactoryBean" >
<property
name="jndiName"
value="${database.jndiName}" />
<property
name="lookupOnStartup"
value="false" />
<property
name="cache"
value="true" />
<property
name="proxyInterface"
value="javax.sql.DataSource" />
</bean>
This works well. However, i can not inject values if i declare beans with spring annotations.
#Component("SecurityFilter")
public class SecurityFilter implements Filter {
public static final String USER = "USER_SESSION_KEY";
public static final String CENTRIFY_USERNAME_KEY = "REMOTE_USERNAME";
#Value("${url.logout}")//I get error here !!!!
private String logoutUrl;
//proper setters and getters.
}
Do you have any idea why i can not access values inside the beans declared using annotations.
Here is my exception
weblogic.application.ModuleException:
at weblogic.servlet.internal.WebAppModule.startContexts(WebAppModule.java:1510)
at weblogic.servlet.internal.WebAppModule.start(WebAppModule.java:482)
at weblogic.application.internal.flow.ModuleStateDriver$3.next(ModuleStateDriver.java:425)
at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:52)
at weblogic.application.internal.flow.ModuleStateDriver.start(ModuleStateDriver.java:119)
Truncated. see log file for complete stacktrace
Caused By: java.lang.IllegalArgumentException: Could not resolve placeholder 'url.logout' in string value [${url.logout}]
at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:173)
at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:125)
at org.springframework.beans.factory.config.PropertyPlaceholderConfigurer$PlaceholderResolvingStringValueResolver.resolveStringValue(PropertyPlaceholderConfigurer.java:255)
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:748)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:745)
Are you sure that the instance of SecurityFilter that actually filters requests is managed by Spring?
By default Filters declared in web.xml are instantiated by servlet container, therefore they are not managed by Spring and Spring annotations such as #Value won't work in them.
However, Spring provides special support for your use case - you can delegate filtering to a component managed by Spring using DelegatingFilterProxy. Declare it in web.xml as follows:
<filter>
<filter-name>SecurityFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>...</filter-mapping>
DelegatingFilterProxy will delegate request filtering to a bean named SecurityFilter (as in your #Component).
The #Value is processed by the java compiler whereas the the XML is parsed by Spring Bean Processor - these are two very different things... Why do you assume that should work in the same manner?
Edit: I read up on it and it seems to actually be possible using the Spring EL, you only have to prefix with # instead of $:
private #Value( "#{application.url.logout}" ) String logoutUrl;
Cheers,
Related
I have an application using a framework that provides certain Spring beans via XML files in the framework. The configuration of my application is currently done partly in XML but mostly with Spring annotations.
Some of the XML bean definitions have parents referring to beans supplied by the framework, e.g.
<bean id="MyBean" parent="FrameworkBean">
<property name="context">
<map merge="true">
<entry key="SomeKey" value-ref="SomeValue" />
</map>
</property>
</bean>
FramwworkBean is defined in an XML file in the framework. There is a chain of bean inheritance. At each step some entries are added to the context:
<bean id="FrameworkBean" parent="AbstractBean">
<map merge="true">...
<bean id="AbstractBean" abstract="true" class="ClassWithContext"/>
I understand the result of all this is construction of a ClassWithContext
instance with a map containing all the entries up the chain.
Is it possible to write Java code to do the same, without duplicating code from the framework XML files?
#Bean("MyBean") ClassWithContext myBean() {
return ??? // code that uses "FrameworkBean" somehow
}
The XML bean definition has no dependency on the type of AbstractBean.
If MyBean can be created by Java code, can that code be written to be equally type-agnostic? Or should I just leave this in XML?
If your "FrameworkBean" is not abstract bean you can try the following:
#Bean
public SomeType myBean(#Qualifier("FrameworkBean") FrameworkBeanType frameworkBean) {
SomeType type = getSomeType();
type.setFrameworkBean(frameworkBean);
return type;
}
I have a session bean like this:
#Component
#Scope(value="session", proxyMode = ScopedProxyMode.TARGET_CLASS)
public class MySession { ... }
How can I enable access to this bean in JSP?
I displayed session data in JSP and I got this:
org.springframework.web.context.request.ServletRequestAttributes.DESTRUCTION_CALLBACK.scopedTarget.mySession
scopedTarget.mySession
So, I tried using ${scopedTarget.mySession.qualites}, but it didn't work.
If you expose spring beans as context properties using this view resolver configuration, then it should be possible to access the bean with a value expression such as #{mySession.qualites} directly:
<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="exposeContextBeansAsAttributes" value="true"/>
</bean>
As an alternative, expose the spring bean to the view model, by using in the #Controller the #ModelAttribute annotation.
I'm working my way through the Spring Framework reference documentation with some very basic application code. So far, I've created an ApplicationContext from an XML file and loaded some beans. I believe I understand this process pretty well. I've loaded some basic beans with attributes based on fundamental types and found that straight-forward.
I'm now working on a composite bean with other beans as its attributes. So far, I've been able to set these attributes using a direct reference to a bean and an inner bean. However, when I try to get the idref element to work (see http://docs.spring.io/spring/docs/3.2.4.RELEASE/spring-framework-reference/html/beans.html#beans-idref-element) I get the following exception:
java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.example.BasicBean] for property 'idRef': no matching editors or conversion strategy found
Code snippets below:
Application Context XML
<?xml version="1.0" encoding="UTF-8"?>
<beans ...>
<bean id="id-bean" class="com.example.BasicBean" scope="singleton">
<property name="value" value="31"/>
</bean>
<bean id="ref-bean" class="com.example.BasicBean" scope="singleton">
<property name="value" value="37"/>
</bean>
<bean id="cb" class="com.example.CompositeBean" scope="singleton">
<property name="id" ref="id-bean"/> <!-- works -->
<property name="inner"> <!-- works -->
<bean class="com.example.BasicBean">
<property name="value" value="43"/>
</bean>
</property>
<property name="idRef"> <!-- exception thrown -->
<idref bean="ref-bean"/>
</property>
</bean>
</beans>
Java App Code
public void main()
{
context = new ClassPathXmlApplicationContext("beans.xml");
CompositeBean cb = context.getBean("cb", CompositeBean.class);
}
Java Bean Code
public class CompositeBean
{
private BasicBean id;
private BasicBean idRef;
private BasicBean inner;
// Default constructor exists
// Setters, getters for each attribute exist
...
}
public class BasicBean
{
private int value;
// Default constructor exists
// Setters, getters for each attribute exist
...
}
Version info: I'm using Eclipse IDE (Kepler), Maven 3.1, Java 7 (1.7.45), Spring 3.2.4
Any thoughts on what I'm doing wrong?
Thanks #Farid for pointing out that I was mis-using the idref attribute in this instance. As the Spring doco points out (which I'd read several times and still missed this) it's designed for passing the id of a bean around a container and not the actual bean. So, stick to the first two means above (ref and inner bean) for passing a bean around.
I have the bean config:
<bean id="PostLoginUpdater" class="xyz.auth.PostLoginUpdater" autowire="byType" />
and
public class PostLoginUpdater implements PostLoginStatePersonalizer {
//#Qualifier("CustomerManager")
#Inject
//#Resource(name = "CustomerManager")
private CustomerManager customerManager;
public void setCustomerManager(CustomerManager customerManager)
{
this.customerManager = customerManager;
}
}
Because there are two beans that implement CustomerManager I get this error:
No unique bean of type [CustomerManager] is defined: expected single
matching bean but found 2
As you can see, I'v tried several combinations (#Inject along with #Qualifier, #Ressource, only #Qualifier) But I don't get rid of this error message.
According to Spring In Depth, #Qualifier can be used along with #Inject. Can't I used them together if I defined autowire="byType" in bean config?
And I don't use <context:annotation-config /> or <context:component-scan />
You should be able to use a combination of '#Inject' and '#Qualifier', if you have multiple beans of the same type. Here is how to configure it -
<bean id="PostLoginUpdater" class="xyz.auth.PostLoginUpdater" autowire="byType" />
<bean id="firstManager" class="xyz.manager.CustomerManager" autowire="byType" >
<qualifier>first</qualifier>
</bean>
<bean id="secondManager" class="xyz.manager.CustomerManager" autowire="byType" >
<qualifier>second</qualifier>
</bean>
If you had two beans of type 'CustomerManager' as shown above, you could use the snippet shown below for injection -
public class PostLoginUpdater implements PostLoginStatePersonalizer {
#Inject
#Qualifier("first")
private CustomerManager customerManager;
public void setCustomerManager(CustomerManager customerManager)
{
this.customerManager = customerManager;
}
}
Also, on a side note -
If you keep using one of the beans more often than another you could use the 'primary' attribute.
For example, in the above example, if you always tend to use 'firstManager', you could mark it as primary as shown below.
<bean id="PostLoginUpdater" class="xyz.auth.PostLoginUpdater" autowire="byType" />
<bean id="firstManager" class="xyz.manager.CustomerManager" autowire="byType" primary="true" >
</bean>
<bean id="secondManager" class="xyz.manager.CustomerManager" autowire="byType" >
<qualifier>second</qualifier>
</bean>
If you have above configuration, the following code will always injects 'firstManager' when no qualifier is used -
public class PostLoginUpdater implements PostLoginStatePersonalizer {
#Inject
private CustomerManager customerManager;
public void setCustomerManager(CustomerManager customerManager)
{
this.customerManager = customerManager;
}
}
It doesn't make any sense to try to autowire by type, and simultaneously specify a name. Choose one approach or the other.
I have also had trouble in the past trying to use #Qualifier with #Inject. One thing to note is that there are two annotations with that name, one in Spring and one in Java:
org.springframework.beans.factory.annotation.Qualifier
javax.inject.Qualifier
However, if using the spring framework one, then the suggested usage is to explicitly name your component via #Component or #Named [#Component("beanName")] (if annotated), or in the <bean> definition. Be aware that autowiring wants the bean name, not the Class name as in your example (i.e. do not use "CustomerManager"). For example, if you have two bean definitions like in Sashi's example:
<bean id="firstManager" class="xyz.manager.CustomerManager" autowire="byType" >
<qualifier>first</qualifier>
</bean>
<bean id="secondManager" class="xyz.manager.CustomerManager" autowire="byType" >
<qualifier>second</qualifier>
</bean>
then declare the field like this:
#Inject
#Qualifier("firstManager")
private CustomerManager customerManager;
I currently load my properties file like so in spring
<context:property-placeholder location="test-esb-project-config.properties"/>
<context:property-placeholder location="esb-project-config.properties"/>
This seems to work great for properties use inside the xml files. How do I load a property from inside my java code now though? OR how do I inject some kind of Bundle or Config object so I don't have to inject 10 properties in one bean?
thanks,
Dean
using annotations #Value(${property}) worked much better and it injected the property into my bean without all the work of xml typing and adding a setter...way too much work going that route.
You can either have setters for each property and wire them with the property reference.
public class MyBean{
public void setFoo(String foo){ /* etc */}
public void setBar(String bar){ /* etc */}
}
<bean class="foo.bar.MyBean">
<property name="foo" value="${my.properties.foo}" />
<property name="bar" value="${my.properties.bar}" />
</bean>
Or you can inject a Properties Object into your Spring Bean.
public class MyBean{
public void setProperties(Properties properties){
// init your properties here
}
}
<bean class="foo.bar.MyBean">
<property name="properties" value="classpath:/path.to.properties" />
</bean>
Both of these would also work without XML when using the #Value annotation.
(see Expression Language > Annotation-based Configuration)