Spring: Inject static member (System.in) via constructor

Question

I wrote some sort of console client for a simple application. To be more flexible, I thought it would be nice to only depend on java.io.Input-/OutputStream, instead of accessing System.in/out directly.

I renamed the class ConsoleClient to StreamClient, added setters and made sure that the instance fields are used instead of System.in/out.

At the moment my client code looks like this:

ApplicationContext appCtx = new ClassPathXmlApplicationContext("...");
StreamClient cc = (StreamClient) appCtx.getBean("streamClient");
cc.setInputStream(System.in);
cc.setOutputStream(System.out);
cc.run();   // start client

Question:

Is there a way to move lines 3 and 4 into the Spring configuration (preferably constructor injection)?

Thanks for your time.

Answer 1

I'm not sure that you can explicitly create a bean using System.out (which I think is what you're asking). However you can create a bean that uses a factory class / method to return an object (in this case System.out)

<bean id="streamOut" class="examples.StreamFactory"
      factory-method="getSystemOut"/>

Answer 2

Use <util:constant ... />:

<util:constant id = "out" static-field="java.lang.System.out" />