Question

I was previously hard coding a path to load a json file like so:

JsonParser parser = jf.createJsonParser(new File("/some/path/here/myapp/WEB-INF/settings.json"));

So I tried to extract it out to a properties file like so, files.properties:

path.to.json=/some/path/here/myapp/WEB-INF/settings.json

Now how can I modify my call to jf.createJsonParser to load the file using the path from the files.properties path.to/json key?

Answer 1

I’m a little confused. Your title indicates that you are looking for a Spring solution, but you are not using IOC here, from what I can tell. Otherwise, you would be injecting the JsonParser bean and not instantiating it within your code.

Without seeing the global structure of what you are doing, I would do the following (assuming that you have Spring properly configured).

applicationContext.xml:

<bean id="jsonParser" factory-bean="<jf bean definition>" factory-method="createJsonParer">
   <constructor-arg>classpath:/settings.json</constructor-arg>
</bean>

Then within your actual class that uses the JsonParser, have it autowired for simplicity sake:

class myClass{
  @Autowired
  JsonParser jsonParser;

  public void myMethod(){
    String data = jsonParser.doSomthingNeatHere()....
  }

}

I’ve assumed that JsonParser is of scope prototype, but you can change it to singleton if that matches your needs more appropriately. As well, I’ve only given you a little pseudo-code to give you the idea of how to allow Spring to manage the life-cycle of the bean as opposed to you instantiating it yourself.

You can read more about Spring 3 and IOC here if you need additional reference.