java - Providing an object for a field in constructing an object in Guice -

suppose have class z, injects class a:

class z {   @inject   public z(.., arg, ..) {     ..   } } 

suppose class has constructor:

@inject public a(b arg0, c arg1, d arg2) {  ... } 

i want injection work normally, except in special cases, want provide 1 of arguments. e.g., constuct using cobject of c class. note constructed using z.

i want because writing functional tests z, want provide different kinds of fakes depending on test. 1 test file contain 1 kind of fake b, or c, or d.

i recommend using modules.override here, has documentation use functional testing. use sparingly, things can messy , hard-to-follow otherwise, this:

@before public void createinjector() {   this.injector = guice.createinjector(       modules.override(new yourzabcdmodule()).with(new abstractmodule() {         @override public void configure() {           bind(b.class).to(fakeb.class);         }       })); } 

or, in modules.override documentation, use smaller modules more-granular combinations:

@before public void createinjector() {   this.injector = guice.createinjector(       new zamodule(),       new fakebmodule(),       new cmodule(),       new dmodule()); }