Introduction

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public JobSupervisor(Provider<JobDAO> jobDaoProvider, Provider<Long> jobTimeoutProvider) {

The Provider<X> interface provides a get() method returning X.  This allows for lazy initialization and/or providing an unknown number of X'es.

Further reading:

• http://www.vogella.com/tutorials/DependencyInjection/article.html
  
• http://square.github.io/dagger/
• http://www.infoq.com/presentations/Dagger

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void Foo() {
int i1=42;
int i2=0;
i2 = f(i1);
int i3 = g(i2);
}

Miscellaneous

Public methods should always check that their arguments follow the JavaDoc restriction with respect to being null, empty, non-negative etc. The ArgumentNotValid class has a number of useful methods for this.

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