PreparedStatement 模糊匹配 结果却：Parameter index out of range (1 > number of parameters, which is 0)

数据库查询中，我们是这样进行模糊匹配的：


select * from user where 1=1  and username like '%林%' limit 0,20
理所当然的，在java代码中你会这么写：


select * from user where 1=1  and username like '%?%' limit 0,20


ps.setString(1, userCondition.getUsername());
如果真这么写，你就等着扑街吧：Parameter index out of range (1 > number of parameters, which is 0)


这时候怎么破？


select * from user where 1=1  and username like ? limit 0,20


ps.setString(1, "%"+userCondition.getUsername()+"%");