Using Google Guava's Objects.ToStringHelper

I have a little trick for Guava's com.google.common.base.MoreObjects.toStringHelper(). I configured IntelliJ IDEA to use it when auto-generating toString() methods. I assume you can do the same in Eclipse. Here's how to do it in Intellij:

• go inside a class
• hit Alt + Insert to popup the "Generate" menu
• choose toString()
• click the "Settings" button
• go to the "Templates" tab
• create a new template named "Guava's MoreObjects.toStringHelper()" (I did it by copying the "ToStringBuilder" template)

• change the template to:

  public String toString() {
  #set ($autoImportPackages = "com.google.common.base.MoreObjects")
      return MoreObjects.toStringHelper(this)
  #foreach ($member in $members)
      .add("$member.name", $member.accessor)
  #end
      .toString();
  }
  

• save the template, close the "Settings" and "Generate toString()" windows

• you can now choose the Guava's MoreObjects.toStringHelper() template when generating toString() methods

When you add a new field to the class, simply re-generate the toString() method (IDEA will ask you to confirm that you want to replace the existing toString() method).

MoreObjects.toStringHelper is intended to help you write toString() methods with a consistent format easily, but it gives you control over what fields you include in toString() and should have performance comparable to writing it out manually. reflectionToString is shorter to type, but it doesn't give you explicit control over the included fields and, well, it uses reflection. I don't see it as a better alternative.

As a side note, I think using toStringHelper looks a lot cleaner if you put one add call per line.

Guava docs

There is a plugin http://sourceforge.net/projects/guavaeclipse/ (really small one) which can generate toString methods (and equals hashcode as well) using Guava classes. This is a nice solution because generated methods are really small and do not clutter the class.

It is worth noting that Objects.toStringHelper has been deprecated (to be removed completely in June 2016) in favor of MoreObjects.toStringHelper. I have copied the default Guava template in my Intellij IDE into a new one that uses the MoreObjects instead. Cheers.

Guava docs

Of the available Eclipse plugins, guavaeclipse is still using MoreObjects.toStringHelper, but Jenerate uses MoreObjects.toStringHelper and works like a charm.

Guava docs