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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The general rule is "put declarations only at the beginning of blocks". We allow one exception from this rule, namely declarations that 1) initialize the variable and 2) depend on previous calculations are allowed be further down the block. Example:

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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