Guice Best Practices

• Minimize mutability
• Inject only direct dependencies
• Use the Injector as little as possible (preferably only once)
• Avoid cyclic dependencies
• Avoid static state
• Use @Nullable
• Modules should be fast and side-effect free
• Be careful about I/O in Providers
• Avoid conditional logic in modules
• Keep constructors as hidden as possible
• Avoid binding Closable resources
• Prefer @Provides methods over the binding DSL
• Avoid calling @Provides methods and @Inject constructors directly
• Don't reuse binding annotations (aka @Qualifiers)
• Organize modules by feature, not by class type
• Document the public bindings provided by modules