Hello I wan't to know how can I set up a bean so that it sets the ScatteredAquireTask to "True".
I've been trying:
<bean id="c3p0Props" class="com.mchange.v2.resourcepool.BasicResourcePool.ScatteredAcquireTask" >
<property name="USE_SCATTTERED_ACQUIRE_TASK" value="true" />
</bean>
I also tried ...resourcepool.experimental.useScatteredAcquireTask... didn't worked. I'm not sure how can I set this on spring. I'm using 0.9.1.2, can't go to 0.9.2.prep1 at the moment. Thanks.
That's because USE_SCATTTERED_ACQUIRE_TASK isn't a property of the ScatteredAcquireTask class (i.e. there's no method called setUSE_SCATTTERED_ACQUIRE_TASK), it's an internal static field of the class that's not accessible to Spring.
You're not going to be able to set that values in a Spring bean defintion, you need to find out how to influence that value by some other means.
Related
I would like to declare a bean for which init-method is not a constant value, but depends on a property:
<bean id="XXX" class="YYY" init-method="${some.property}"/>
I have a PropertyPlaceholderConfigurer bean already configured, but unfortunately spring tries to call method named ${some.property} instead of the property value.
What should I configure in order to spring call the method pointer by some.property value?
To do this, you'll need to include the following bean and put the path to the properties file in the location property:
<bean class="org.springframework.beans.factory.config.PropertiesFactoryBean" id="appConfig">
<property name="location" value="classpath:appConfig.properties"></property>
</bean>
Let's suppose your properties file contains the following entry:
init_method = test
Then, by using your own code snippet, you should refer to aforementioned property in this way:
<bean id="XXX" class="YYY" init-method="#{appConfig['init_method ']}"/>
The appConfig must match bean's id declared on the first snippet
Is it possible to create to bean with same id with same class with different property in spring ? Like:
<bean id ="a" class= "com.tofek.A"
<property message = "khan"/>
</bean>
<bean id = "a" class = "com.tofek.A"
<property message="tofek"/>
</bean>
As per my understanding it will create, but while fetching the bean using getBean() method it will give exception like NoBeanDefinitionFoundException.
Please correct my understanding if I'm wrong?
Make sure your spring context is loaded sucessfully.
Answering your question. You can have two identical bean definitions in two different sprintContext configurations.
The bean from second context will override bean created by first one.
For example :
context1.xml
<bean id="bean1" class="org.springframework.beans.TestBean"/>
context2.xml
<bean id="bean1" class="org.springframework.beans.TestBean"/>
then, the bean from context2.xml will override bean created by contex1.xml.
It of course depends on order of creating spring contexts. The laters overrides the ones made before.
You can use getBean() to fetch bean by type or name. In this case, both bean have same id's and types, the spring wouldn't know which one you want to fetch.
I have one spring configuration file with entry like below...
<bean id="beanId" class="a.b.c.d.MyBean">
<property name="firstProperty" value="report_{date}.xls"/>
</bean>
Somewhere in my java code, I am fetching this bean and then its property "firstProperty" later.
I am little curious, when I get the value of property "firstProperty" I get report_.xls i.e report_20130307.xls
I have searched all my code including bundles, xmls but not clear that where we are setting {date} with todays timestamp.
Do you have any clue where we can do this?
Thanks
Jai
It is the property-placeholder mechanism.
Read more on http://static.springsource.org/spring/docs/3.2.x/spring-framework-reference/html/xsd-config.html#xsd-config-body-schemas-context-pphc.
In most of the cases, the values to property are set from properties file using expression language. Like
<bean id="dataSource" class="a.b.c.d.DataSource">
<property name="databaseUrl" value="{db.url}"/>
</bean>
Or if the property is a ref to another bean, e.g. Object B is member variable of Object A.
<bean id="refA" class="a.b.c.d.A">
<property name="b" ref="refB"/>
</bean>
<bean id="refB" class="a.b.c.d.B">
</bean>
Its quite simple guys...as we know setter are called for each property. So same in my case,
In bean we are setting variable "firstProperty" + today timestamp like below.
public void setfirstProperty(String firstProperty) {
this.firstProperty = firstProperty + <methodToReplaceDateStringWithTimeStamp>;
}
Thanks
Jai
Before upgrading to Spring 3 I had this in my applicationContext.xml file:
<bean class="com.northgateis.pole.ws.PolePayloadValidatingInterceptor">
<property name="validateRequest" value="${validateRequest}" />
<property name="validateResponse" value="${validateResponse}" />
</bean>
where ${validateRequest) and ${validateRequest) refer to properties that may or may not be defined in my properties file.
In Spring 2, if these proeprties were not present in the properties file the setters on the bean were not called and so the defaults hard-coded in PolePayloadValidatingInterceptor were used.
After upgrading to Spring 3, it seems the behaviour is different: If the properties are not present in the properties file I get the following exception:
SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanDefinitionStoreException: Invalid bean definition with name 'annotationMapping' defined in class path resource [com/northgateis/pole/ws/applicationContext-ws.xml]: Could not resolve placeholder 'validateRequest'
at org.springframework.beans.factory.config.PropertyPlaceholderConfigurer.processProperties(PropertyPlaceholderConfigurer.java:272)
at org.springframework.beans.factory.config.PropertyResourceConfigurer.postProcessBeanFactory(PropertyResourceConfigurer.java:75)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:640)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:615)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:405)
at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:272)
I tried dabbling with Spring EL but the following doesn't seem to work:
<bean class="com.northgateis.pole.ws.PolePayloadValidatingInterceptor">
<property name="validateRequest" value="${validateRequest?:true}" />
<property name="validateResponse" value="${validateResponse?:false}" />
</bean>
The value after the Elvis operator is always used, even when the properties are defined in the proeprties file. Interesting that the syntax is accepted.
Any suggestions?
It looks like Spring 3's handling of default values with the Elvis operator was rather broken. This has apparently been fixed (see SPR-7209) in the fresh-out-of-the-oven Spring 3.0.3, and the correct syntax should be the rather baroque:
#{${validateRequest}?:true}
There's no need for Spring EL for setting a default value for a missing property when resolving it with a placeholder configurer. Simply use ${validateRequest:true}. The "Elvis operator" is not concerned with resolving placeholders, it just relies on whatever input the placeholder configurer provides.
See SPR-4785.
How can I create a bean of type Class?
I found a way using getClass() but that requires an instance and cannot be used via factory-method since it is not static. It also requires an extraneous bean be created for this express purpose:
<bean id="foo" class="Foo" />
<bean id="fooClass" factory-bean="foo" factory-method="getClass" />
This isn't so bad if the Foo class is easy to construct, but what if the constructor has required parameters?
I then need to create a Set of Class to wire into another bean via a property. I would create the Set such as:
<util:set id="classSet">
<ref local="fooClass"/>
</util:set>
If you really wanted to do what you describe, then you can do it like this:
<bean id="myClass" class="java.lang.Class" factory-method="forName">
<constructor-arg value="com.MyClass"/>
</bean>
But as #ChssPly76 said, if you want to inject it into another bean, you only need inject the class name, and Spring will auto-convert it into a class instance for you.
Why would you? Can you provide an example where that's actually needed?
If you only need this as a dependency (e.g. some other bean has a property of type Class), Spring's built-in ClassEditor property editor would convert a regular string into a Class instance with that name for you:
<property name="someClass" value="java.lang.String"/>
The above would result in setSomeClass(Class clazz) setter being called on the bean whose property that is.