Spring Related-- @Autowired with Map<String, myObjectType> is not initialized in the IoC container

[hisham ragheb]

hi,


i created a Person bean which has a private field named degrees of type Map<String,Degree> and annotated it with @Autowired
i have also 2 classes who are different implementations of the Degree class, i defined and initialized them in the beans.xml

the problem arise when i try to get this field using its getter method where i always gets null. This mean this Map<String,Degree> is not initialized with the target beans

why is that?


regards

[Jaikiran Pai]

Moving to Application Frameworks forum.

[David Newton]

Without any code or configuration I don't see how anybody could help.

[David Newton]

Moving to Spring.

[Hong Anderson]

You should have a Map bean specified.

[hisham ragheb]

Kengkaj Sathianpantarit wrote:You should have a Map bean specified.

The problem that @Autowire somtimes works and most time it dont when its used with collections(List,Set Map)..the container dont create the collection and inject the beans by type in it

this is my problem...the collection returned sometimes is null other times contains the injected beans

I dont know why

[Hong Anderson]

Please post your configuration.

[hisham ragheb]

Kengkaj Sathianpantarit wrote:Please post your configuration.

ok..but becareful that naming may not make so much sense here


A Person class:

   
package springtest;

import java.util.Map;
import org.springframework.beans.factory.annotation.Autowired;


public class Person {

    private String name;
    private int age;
    @Autowired private Map<String,MSC> msc;

    public Person() {
    }

    public Map<String,MSC> getMsc() {
        return msc;
    }


    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }


    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

}

A Career Abstract class:

    
package springtest;

public abstract class Career {

    protected String degree;
    private String title;  
    private float salary;
    

    public float getSalary() {
        return salary;
    }

    public void setSalary(float salary) {
        this.salary = salary;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public abstract String getDegree();
    public abstract void setDegree(String degree);
}

(Subclass of Career) MSC class:

package springtest;


public class MSC extends Career{



    public String getDegree() {
        return degree;
    }

    public void setDegree(String degree) {
        this.degree = degree;
    }

}   

The beans.xml

    
<?xml version="1.0" encoding="UTF-8"?>

<beans  xmlns:xsi='http://www.w3.org/2001/XMLSchema-instance'
   xmlns='http://www.springframework.org/schema/beans'
   xmlns:ns1='http://www.springframework.org/schema/context'
   xsi:schemaLocation='http://www.springframework.org/schema/beans springtest/spring-beans-2.5.xsd
   http://www.springframework.org/schema/context springtest/spring-context-2.5.xsd' default-dependency-check="all">


<ns1:annotation-config/>


<bean id="person" class="springtest.Person"    >
    <property name="name" value="jamz"/>
    <property name="age" value="28"/>

</bean>

<bean id="A" class="springtest.MSC" >
    <property name="degree" value="Msc"/>
    <property name="title" value="Senior SOA Architect"/>
    <property name="salary" value="9000.100"/>
</bean>


<bean  id="B" class="springtest.MSC" >
    <property name="degree" value="Meng"/>
    <property name="title" value="Senior Security Engineer"/>
    <property name="salary" value="11520.66"/>
</bean>

</beans>

The Main class (for testing):

    
package springtest;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;


public class Main {

    
    public static void main(String[] args) {
        // TODO code application logic here
        Resource rs=new ClassPathResource("springtest/beans.xml");
        BeanFactory fac=new XmlBeanFactory(rs);

        Person p=(Person)fac.getBean("person");

       System.out.println("Person degree: "+p.getMsc().get("A").getDegree());
       System.out.println("Person title: "+p.getMsc().get("A").getTitle());
       System.out.println("Person salary: "+p.getMsc().get("A").getSalary());

       System.out.println("Person degree: "+p.getMsc().get("B").getDegree());
       System.out.println("Person title: "+p.getMsc().get("B").getTitle());
       System.out.println("Person salary: "+p.getMsc().get("B").getSalary());



    }

}

also, thank you for your concern

[Hong Anderson]

There is no Map bean. You need a Map bean.

[hisham ragheb]

Kengkaj Sathianpantarit wrote:There is no Map bean. You need a Map bean.

I'm trying similar example as the one in (Apress Spring Recipes) book, but he didn't define Map bean in this example?

can you show me how can i do it

[Freddy Wong]

    
<util:map id="msc" key-type="java.lang.String" value-type="springtest.MSC">
        <entry key="test1" value-ref="A"/>
        <entry key="test2" value-ref="B"/>
</util:map>

[hisham ragheb]

Freddy Wong wrote:

    
<util:map id="msc" key-type="java.lang.String" value-type="springtest.MSC">
        <entry key="test1" value-ref="A"/>
        <entry key="test2" value-ref="B"/>
</util:map>

im using spring 2.5.5

so i tried to use this which didnt work

<util:map id="msc" map-class="java.util.HashMap">
    <entry  key="A">
        <ref local="A"/>
    </entry>
   <entry key="B">
        <ref local="B"/>
    </entry>
</util:map>

i tried this also which didnt work

<bean id="msc"  class="org.springframework.beans.factory.config.MapFactoryBean" >
    <property name="targetMapClass">
         <value>java.util.HashMap</value>
    </property>
    <property name="sourceMap">
        <map key-type="java.lang.String" value-type="springtest.MSC">
            <entry key="A">
                <ref local="A"/>
            </entry>
            <entry key="B">
                <ref local="B"/>
            </entry>
        </map>
    </property>
</bean>

i still always get NullPointerException when i try to access the Map

is there a way to debug the framework, everytime i use the debugger it dont step into the spring classes

[Freddy Wong]

is there a way to debug the framework, everytime i use the debugger it dont step into the spring classes

Yes, but you need to have Spring source code in order to step into Spring classes.