#### Utility: compare with alternatives


        There is always *some* alternative to adding a new feature to Guava, even if it's just
        forking Guava yourself.


        We want to see that new features have some significant advantage over the alternatives.
        These advantages can take
        [many forms](https://github.com/google/guava/wiki/PhilosophyExplained#utility), but taking

        // respectively. Using a simple replacement of these patterns will allow them
        // to specify the absolute path to these files in a customized components.xml
        // file. Ideally, we'd do full pattern-evaluation against the sysprops, but this
        // is a first step. There are several replacements below, in order to normalize

# Testing Dependencies with Overrides { #testing-dependencies-with-overrides }

## Overriding dependencies during testing { #overriding-dependencies-during-testing }

There are some scenarios where you might want to override a dependency during testing.

You don't want the original dependency to run (nor any of the sub-dependencies it might have).

That when called, return instances of classes of the same name.

So, you import `Query`, which is a function. And when you call it, it returns an instance of a class also named `Query`.

These functions are there (instead of just using the classes directly) so that your editor doesn't mark errors about their types.

That way you can use your normal editor and coding tools without having to add custom configurations to disregard those errors.

You can also read more about them in the [Wikipedia for Environment Variable](https://en.wikipedia.org/wiki/Environment_variable).

In many cases it's not very obvious how environment variables would be useful and applicable right away. But they keep showing up in many different scenarios when you are developing, so it's good to know about them.

                current.println("        body: |")
                body.eachLine { current.println("          $it") }
            }
            /* Catch any shard failures. These only cause a non-200 response if
             * no shard succeeds. But we need to fail the tests on all of these
             * because they mean invalid syntax or broken queries or something
             * else that we don't want to teach people to do. The REST test

These particular phases in a plugin’s lifecycle can probably be generalized to all plugins so could be something implemented in all plugins. Here we could have the descriptor either point to methods for each of these phases to execute or we could create a lifecycle in Plexus for these phases.

For a particular application plugin there will be a declarative descriptor for that plugin type.

 *
 *  2. If there is a connection in the pool that can satisfy the request it is used. Note that it is
 *     possible for shared exchanges to make requests to different host names! See
 *     [RealConnection.isEligible] for details.
 *
 *  3. Attempt plans from prior connect attempts for this call. These occur as either follow-ups to

Since HTTP requests frequently happen in parallel, connection pooling must be thread-safe.

There is some assistance in the IDE for this plus a lot of validation that is applied at build time and on CI, but it is useful to keep these constraints in mind as well.

See [Gradle runtimes](runtimes.md) for a list of these runtimes and more details.

### Build execution model