Monthly Archive for May, 2008

It’s even easier than it looks.

<bean id="myList" class="java.util.ArrayList">
    <constructor-arg>
        <list>
            <value type="org.pkg.ExampleEnum">EXAMPLE_ONE</value>
            <value type="org.pkg.ExampleEnum">EXAMPLE_TWO</value>
        </list>
    </constructor-arg>
</bean>

Too much work for you? Well, if you inject a collection into a Java Bean that defines that property with generics, the type definition isn’t even necessary! Spring determines that type from the generic.

Also, if you’re interesting in injecting a map using enums as keys, you may with to utilize the java.util.EnumMap data structure. Inject a HashMap instead of a ArrayList and build an EnumMap in the setter of the bean.

<bean id="javaBean" class="org.pkg.MyBean">
    <property name="exampleMap">
        <map>
            <entry key="EXAMPLE_ONE" value="myValueForExampleOne" />
            <entry key="EXAMPLE_TWO" value="myValueForExampleTwo" />
        </map>
    </property>
</bean>

…

//javaBean...
private Map<ExampleEnum, String> = null;

//public setter creates efficient EnumMap
public void setExampleMap(Map<ExampleEnum, String> simple) {
    this.enumMap = new EnumMap<ExampleEnum, String>(simple);
}