AbstractConfig implements Config { @Override public String toString() { return super.toString(); }  @Override String toString(); @Override String toLoggerString(); Map<String, String> getConfigPropsFromSource(ConfigSource source); Map<String, String> getConfigPropsDefinedUsingFiles(); @Override Properties toProperties(); @Override void toFile(File file); @Override boolean sameAs(Config other); @Override String getAttribute(String name); @Override ConfigSource getAttributeSource(String name); @Override void setAttribute(String name, String value, ConfigSource source); @Override String getAttributeDescription(String name);  }
@Test public void toStringCanBeMocked() { when(abstractConfig.toString()).thenReturn("STRING"); assertThat(abstractConfig.toString()).isEqualTo("STRING"); }