}
@Test
public void testWriteFrom() throws Exception {
DataSourceProvider p = new DataSourceProvider();
DataSource ds = new InputStreamDataSource(new ByteArrayInputStream("image".getBytes()),
"image/png");
ByteArrayOutputStream os = new ByteArrayOutputStream();
p.writeTo(ds, DataSource.class, DataSource.class, new Annotation[]{},
MediaType.valueOf("image/png"), new MetadataMap<String, Object>(), os);
assertEquals("image", os.toString());