How to test Guice Singleton?

Posted by 01 on Stack Overflow See other posts from Stack Overflow or by 01
Published on 2010-05-22T07:21:29Z Indexed on 2010/05/22 7:30 UTC
Read the original article Hit count: 225

Filed under:

guice

|

singleton

|

unit-testing

|

module

|

change

Guice Singletons are weird for me

First I thought that

IService ser = Guice.createInjector().getInstance(IService.class);
System.out.println("ser=" + ser);
ser = Guice.createInjector().getInstance(IService.class);
System.out.println("ser=" + ser);

will work as singleton, but it returns

ser=Service2@1975b59
ser=Service2@1f934ad

its ok, it doesnt have to be easy.

Injector injector = Guice.createInjector();
IService ser = injector.getInstance(IService.class);
System.out.println("ser=" + ser);
ser = injector.getInstance(IService.class);
System.out.println("ser=" + ser);

works as singleton

ser=Service2@1975b59
ser=Service2@1975b59

So i need to have static field with Injector(Singleton for Singletons)

how do i pass to it Module for testing?

© Stack Overflow or respective owner

Related posts about guice

Injection with google guice does not work anymore after obfuscation with proguard

as seen on Stack Overflow - Search for 'Stack Overflow'
Has anyone ever tried to combine the use of google guice with obfuscation (in particular proguard)? The obfuscated version of my code does not work with google guice as guice complains about missing type parameters. This information seems to be erased by the transformation step that proguard does… >>> More
Injecting generics with Guice

as seen on Stack Overflow - Search for 'Stack Overflow'
I am trying to migrate a small project, replacing some factories with Guice (it is my first Guice trial). However, I am stuck when trying to inject generics. I managed to extract a small toy example with two classes and a module: import com.google.inject.Inject; public class Console<T> { … >>> More
Guice and JSF 2

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to use Guice to inject properties of a JSF managed bean. This is all running on Google App Engine (which may or may not be important) I've followed the instructions here: http://code.google.com/docreader/#p=google-guice&s=google-guice&t=GoogleAppEngine One problem is in the… >>> More
What problem does Peaberry for Guice solve?

as seen on Stack Overflow - Search for 'Stack Overflow'
I understand the problem that OSGI solved thanks to this question.... http://stackoverflow.com/questions/106222/what-does-osgi-solve And I am already convinved that Guice is amazing so I'm curious what this OSGI integration for Guice known as "peaberry" is supposed to do, it seems to be popping… >>> More
How test guice injections?

as seen on Stack Overflow - Search for 'Stack Overflow'
I gave to Google Guice the responsability of wiring my objects. But, How can I test if the bindings are working well. For example, suppose we have a class A which has a dependence B. How can I test than B is injected correctly. class A { private B b; public A() {} @Inject public… >>> More

Related posts about singleton

Singleton design pattern vs Singleton beans in Spring container

as seen on Stack Overflow - Search for 'Stack Overflow'
As we all know we have beans as singleton by default in Spring container and if we have a web application based on Spring framework then in that case do we really need to implement Singleton design pattern to hold global data rather than just creating a bean through spring. Please bear with me if… >>> More
Java Singleton Pattern

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm used the Singleton Design Pattern public class Singleton { private static final Singleton INSTANCE = new Singleton(); // Private constructor prevents instantiation from other classes private Singleton() {} public static Singleton getInstance() { return INSTANCE; } } My… >>> More
Static vs Singleton in C# (Difference between Singleton and Static)

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
Recently I have came across a question what is the difference between Static and Singleton classes. So I thought it will be a good idea to share blog post about it.Difference between Static and Singleton classes:A singleton classes allowed to create a only single instance or particular class. That… >>> More
Difference between Singleton implemention using pointer and using static object

as seen on Stack Overflow - Search for 'Stack Overflow'
EDIT: Sorry my question was not clear, why do books/articles prefer implementation#1 over implementation#2? What is the actual advantage of using pointer in implementation of Singleton class vs using a static object? Why do most books prefer this class Singleton { private: static Singleton… >>> More
Trying to change variables in a singleton using a method

as seen on Stack Overflow - Search for 'Stack Overflow'
I am trying to use a singleton to store variables that will be used across multiple view controllers. I need to be able to get the variables and also set them. How do I call a method in a singleton to change the variables stored in the singleton. total+=1079; [var setTotal:total]; where var is… >>> More