Is Map> possible to declare in Spring

Question

I have a class with the following constructor:

public MyClass(Map<String s, Collection<Object>> co){
    //impl
}

I need to invoke it via Spring bean's declarations. I tried to do something like this:

<bean id="toInject" class="path.toSomClass" />

<bean id="myBean" class="path.to.MyClass">
    <constructor-arg>
        <map>
            <entry key="String" 
        value-ref="_WHAT_SHOULD_I_WRITE_HERE_TO_DECLARE_A_COLLECTION_FROM_THE_ONLY_toInject">
        </map>
    </constructor-arg>
</bean>

I'm not concerned about the type of the Collection (It may be a List<T> as well as Set<T>, or anything else implementing Collection<T>).

What is element type in Collection? – LHA Oct 27 '15 at 13:49 — LHA, Oct 27 '15 at 13:49
@Loc They are just `Object`s. – St.Antario Oct 27 '15 at 13:55 — St.Antario, Oct 27 '15 at 13:55

Tunaki · Accepted Answer · 2015-10-27T13:56:24.613

1

You can declare a <list> element as part of the value for the entry, like this:

<bean id="myBean" class="path.to.MyClass">
    <constructor-arg>
        <map>
            <entry key="String">
                <list>
                    <ref bean="toInject" />
                </list>
            </entry>
        </map>
    </constructor-arg>
</bean>

edited Oct 27 '15 at 13:56

answered Oct 27 '15 at 13:50

Tunaki

132,869
46
340
423

score 1 · Answer 2 · answered Oct 27 '15 at 13:51

Dependency injection happens at runtime, so no type arguments exist anymore at that time.

This configuration should work:

<bean id="myBean" class="path.to.MyClass">
    <constructor-arg>
        <map>
            <entry key="String">
                <list>
                     <value>Your value here, or</value>
                     <ref bean="yourBeanHere" />
                </list>
            </entry>
        </map>
    </constructor-arg>
</bean>

Is Map> possible to declare in Spring

2 Answers2