java多条件查询_java web中的多条件查询

要查询的字段有：cname gender cellphone email

首先定义sql的前半段固定代码

"select * from t_customer where 1=1"

当cname选项被选中时，

sql.append(" and cname like ?");

sql查询语句就变成了：

select * from t_customer where 1=1 and cname like ?

当gender也被选中时，sql查询语句就变成了：

select * from t_customer where 1=1 and cname like ? and gender=?

以此类推

public Listquery(Customer criteria) {try{//给出sql模板,为了便于后面添加sql语句

StringBuilder sql =new StringBuilder("select * from t_customer where 1=1");//给出parmas

List parmas = new ArrayList();

String cname=criteria.getCname();if(cname != null && !cname.trim().isEmpty()){

sql.append("and cname like ?");

parmas.add("%" +cname+ "%");

}

String gender=criteria.getGender();if(gender != null && !gender.trim().isEmpty()){

sql.append("and gender=?");

parmas.add(gender);

}

String cellphone=criteria.getCellphone();if(cellphone != null && !cellphone.trim().isEmpty()){

sql.append("and cellphone like ?");

parmas.add("%" +cellphone+ "%");

}

String email=criteria.getEmail();if(email != null && !email.trim().isEmpty()){

sql.append("and email like ?");

parmas.add("%" +email+ "%");

}return qr.query(sql.toString(), new BeanListHandler(Customer.class),parmas.toArray());

}catch(SQLException e){throw newRuntimeException(e);

}

}