Cannot create copy of Collection type [java.util.ArrayList] - injecting original ...

[calvinta]

Hi,

I am trying to inject a list into a constructor that expects a java.util.List<java.math.BigDecimal> object as the argument. Here is my XML Spring config:

<bean id="myBean" class="MyClass">
<constructor-arg>
<list>
<value>0.913291139</value>
<value>0.086708861</value>
</list>
</constructor-arg>
</bean>

Here is an excerpt of MyClass:

public class MyClass implements MyInterface {

public MyClass(List<BigDecimal> numbers) {
this.numbers = new ArrayList<BigDecimal>(numbers);
}

....
}


However, when my app starts up, I get the following exception:

org.springframework.beans.TypeConverterDelegate: Cannot create copy of Collection type [java.util.ArrayList] - injecting original Collection as-is { java.lang.InstantiationException: mypackage.MyInterface
at java.lang.Class.newInstance0(Class.java:340)
at java.lang.Class.newInstance(Class.java:308)
at org.springframework.beans.TypeConverterDelegate.co nvertToTypedCollection(TypeConverterDelegate.java: 556)
at org.springframework.beans.TypeConverterDelegate.co nvertIfNecessary(TypeConverterDelegate.java:231)
at org.springframework.beans.TypeConverterDelegate.co nvertIfNecessary(TypeConverterDelegate.java:104)

I looked at TypeConverterDelegate. It looks like it tried to make a copy of the list by calling newInstance on java.util.List.class but it failed because java.util.List is abstract.

Does anyone know what is the proper way of injecting a list into a constructor?

Many thanks.

Calvin

[Javaid Bolaky]

Hi Calvin,

Think that it should be working because it worked for me,

Please try to creating only a spring beans with constructor injection of list in another project and see what happens.

It could be some other factors giving you this error.

Thanks