Book book = new Book();
while(rs.next()){
book.setId(rs.getInt("id"));
book.setIsbn(rs.getString("isbn"));
book.setTitle(rs.getString("title"));
book.setCopyright(rs.getString("copyright"));
book.setEditionnumber(rs.getInt("editionNumber"));
book.setImagefile(rs.getString("imageFile"));
book.setPrice(rs.getDouble("price"));
book.setPublisherid(rs.getString("publisherID"));
System.out.println("bookdao lsdjfldsjfld"+book.getImagefile());
lists.add(book);
}
return lists;
--------------------------------------------------------------
Book book = null;
while(rs.next()){
book = new Book();
book.setId(rs.getInt("id"));
book.setIsbn(rs.getString("isbn"));
book.setTitle(rs.getString("title"));
book.setCopyright(rs.getString("copyright"));
book.setEditionnumber(rs.getInt("editionNumber"));
book.setImagefile(rs.getString("imageFile"));
book.setPrice(rs.getDouble("price"));
book.setPublisherid(rs.getString("publisherID"));
System.out.println("bookdao lsdjfldsjfld"+book.getImagefile());
lists.add(book);
book = null;
}
return lists;对于以上两种方式处理的代码,结果却不同。令我疑惑的是,每次System.out.println的值是不同的,但add到list后,
所有的book都是相同的值,就好象是,在add到list时,add的是同一个book对象,这是为什么?
while(rs.next()){
book.setId(rs.getInt("id"));
book.setIsbn(rs.getString("isbn"));
book.setTitle(rs.getString("title"));
book.setCopyright(rs.getString("copyright"));
book.setEditionnumber(rs.getInt("editionNumber"));
book.setImagefile(rs.getString("imageFile"));
book.setPrice(rs.getDouble("price"));
book.setPublisherid(rs.getString("publisherID"));
System.out.println("bookdao lsdjfldsjfld"+book.getImagefile());
lists.add(book);
}
return lists;
--------------------------------------------------------------
Book book = null;
while(rs.next()){
book = new Book();
book.setId(rs.getInt("id"));
book.setIsbn(rs.getString("isbn"));
book.setTitle(rs.getString("title"));
book.setCopyright(rs.getString("copyright"));
book.setEditionnumber(rs.getInt("editionNumber"));
book.setImagefile(rs.getString("imageFile"));
book.setPrice(rs.getDouble("price"));
book.setPublisherid(rs.getString("publisherID"));
System.out.println("bookdao lsdjfldsjfld"+book.getImagefile());
lists.add(book);
book = null;
}
return lists;对于以上两种方式处理的代码,结果却不同。令我疑惑的是,每次System.out.println的值是不同的,但add到list后,
所有的book都是相同的值,就好象是,在add到list时,add的是同一个book对象,这是为什么?
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while(rs.next()){
Book book = new Book();
book.setId(rs.getInt("id"));
book.setIsbn(rs.getString("isbn"));
book.setTitle(rs.getString("title"));
book.setCopyright(rs.getString("copyright"));
book.setEditionnumber(rs.getInt("editionNumber"));
book.setImagefile(rs.getString("imageFile"));
book.setPrice(rs.getDouble("price"));
book.setPublisherid(rs.getString("publisherID"));
System.out.println("bookdao lsdjfldsjfld"+book.getImagefile());
lists.add(book);
}
return lists;
while(rs.next()){
book = new Book();
book.setId(rs.getInt("id"));
book.setIsbn(rs.getString("isbn"));
book.setTitle(rs.getString("title"));
book.setCopyright(rs.getString("copyright"));
book.setEditionnumber(rs.getInt("editionNumber"));
book.setImagefile(rs.getString("imageFile"));
book.setPrice(rs.getDouble("price"));
book.setPublisherid(rs.getString("publisherID"));
System.out.println("bookdao lsdjfldsjfld"+book.getImagefile());
lists.add(book);
book = null;
}
return lists;这种
打印出来的属性值都是不一样的啊,就算是同一个对象 ,但我们已经修改了他的属性值啊?
但最后,lists中,存放的所有对象,他们都有相同的属性值。求解释……