Book srcBook = new Book();
srcBook.setName("Jakarta Commons Cookbook");
Book destBook = new Book();
PropertyUtils.copyProperties(destBook, srcBook);

// 输出
// Jakarta Commons Cookbook
System.out.println(destBook.getName());
PropertyUtils.copyProperties()将检索源bean中所有的属性,然后将其值分配给目标bean中相同的属性,如果上面的例子中Book bean有一个author属性,类型是Person,这个方法将分配其的references给destBook,也就是说copyProperties()方法不会克隆属性的值.看下面的代码片段

Person author = new Person();
author.setName("Timothy M. O'Brien");
Book srcBook = new Book();
srcBook.setName("Jakarta Commons Cookbook");
srcBook.setAuthor(author);

Book destBook = new Book();
PropertyUtils.copyProperties(destBook, srcBook);

// 结果输出
// Author objects identical
if (srcBook.getAuthor() == destBook.getAuthor()) {
System.out.println("Author objects identical");
}
copyProperties()方法也能将Map中的内容分酌给bean,如果key同目标bean的属性名相同的话

Map srcMap = new HashMap();
srcMap.put("name", "Jakarta Commons Cookbook");
Book destBook = new Book();
PropertyUtils.copyProperties(destBook, srcMap);
// 输出
// Jakarta Commons Cookbook
System.out.println(destBook.getName());