title: Cannot check for missing property if declared in @ConfigurationProperty
body: <p>We have built a Spring Boot starter that describes it's configuration in a class annotated with @ConfigurationProperties:</p>
  
  <pre><code>@ConfigurationProperties(name = "foo.bar")
  public class FooConfiguration {
      public String baz;
  }
  </code></pre>
  
  <p>Outside the starter I want to perform some action depending on whether the property is <em>not</em> set using the @ConditionalOnProperty annotation:</p>
  
  <pre><code>@Bean
  @ConditionalOnProperty(name = "foo.bar.baz", matchIfMissing=true)
  public FooReplacement moo() {
      return new FooReplacement();
  }
  </code></pre>
  
  <p>However, this condition never matches if the foo.bar.baz property is described in a class annotated with @ConditionProperties. If it's not described in such a class, the @ConditionalOnProperty annotation works just fine.</p>
  
  <p>We are using Spring Boot 1.4</p>
  
  <p>So, is the way Spring Boot is expected to work or have we spotted a bug?</p>