In a gradle file, I need to add the dependency of `com.google.guava:guava:16.0`, I can write:

```
compile group: 'com.google.guava', name: 'guava', version: '16.0'

```

without `configuration`.

Or use configuration `default` or `compile` or `runtime` or `test`:

```
compile configuration: 'default', group: 'com.google.guava', name: 'guava', version: '16.0'
compile configuration: 'compile', group: 'com.google.guava', name: 'guava', version: '16.0'
compile configuration: 'runtime', group: 'com.google.guava', name: 'guava', version: '16.0' 
compile configuration: 'test', group: 'com.google.guava', name: 'guava', version: '16.0' 

```

There is no error when I run `gradle compileJava`.

But if I try other values, like `testCompile` or `any-other-value`, it will report:

FAILURE: Build failed with an exception.

```
* What went wrong:
Could not resolve all dependencies for configuration ':compile'.
> Module version :gradle-test:unspecified, configuration 'compile'
  declares a dependency on configuration 'testCompile' which is
  not declared in the module descriptor for com.google.guava:guava:16.0

```

Where can I find the `module descriptor` file and the configurations it declares?

I found the <https://repo1.maven.org/maven2/com/google/guava/guava/16.0/guava-16.0.pom>, is it the `module descriptor`? But I can't find anything about `default/compile/...` configurations.