### Question:
PluginMetadataImpl implements PluginMetadata { @Override public void addContentType( String contentType ) { this.contentTypes.add( contentType ); } PluginMetadataImpl( File rootDirectory ); @Override ManifestUpdater getManifestUpdater(); @Override Document getBlueprint(); @Override void setBlueprint( Document blueprint ); @Override void writeBlueprint( String name, OutputStream outputStream ); @Override FileWriter getFileWriter( String path ); @Override OutputStream getFileOutputStream( String path ); @Override void addContentType( String contentType ); @Override List<String> getContentTypes(); @Override void executeAtEnd( Runnable runnable );  }### Answer:
@Test public void testAddContentType() throws Exception { PluginMetadataImpl pluginMetadata = new PluginMetadataImpl( mockRootDirectory ); assertEquals( 0, pluginMetadata.getContentTypes().size() ); pluginMetadata.addContentType( "text/xml" ); assertEquals( 1, pluginMetadata.getContentTypes().size() ); assertEquals( "text/xml", pluginMetadata.getContentTypes().get( 0 ) ); }