Fuzzy query:
- querying the passed name, password attribute column
- need to define a getForListWithCriteriaCustomer (CriteriaCustomer cc) in CustomerDAO interface.
Wherein CriteriaCustomer for packaging query: name, address, phone.
Because the query many times and domain class is not the same, so to make a separate class
- fight SQL:
- SQL："SELECT ID,NAME,PASSWORD FROM CUSTOMER WHERE"+"NAME LIKE ? AND PASSWORD LIKE ? ";
- In order to correctly fill placeholders, rewritten getter CriteriaCustomer of:
- Modify the Servlet : parameter acquisition request; CriteriaCustomer encapsulate the request parameter object, calls getForListWithCriteriaCustomer (CriteriaCustomer cc) Method
step:
1. First, the method to add CustomerDAO interface.
public List<Customer> getListWithCirteriaCustomer(CriteriaCustomer cc);
2. Create a CriteriaCustomer class to encapsulate the member variables
package com.mvcapp.entity;
public class CriteriaCustomer {
private String name;
private String password;
public CriteriaCustomer(String name, String password) {
this.name = name;
this.password = password;
}
public CriteriaCustomer() {
}
public String getName() {
if (name == null){
name="%%";
}else{
name="%"+ name +"%";
}
return name;
}
@Override
public String toString() {
return "CriteriaCustomer{" +
"name='" + name + '\'' +
", password='" + password + '\'' +
'}';
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
if (password == null){
password="%%";
}else{
password="%"+ password +"%";
}
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
3. The implementation of the method implemented in the class CustomerDAOimpl
public List<Customer> getListWithCirteriaCustomer(CriteriaCustomer cc) {
String sql = "SELECT ID,NAME,PASSWORD FROM CUSTOMER WHERE" + " NAME LIKE ? AND PASSWORD LIKE ?";
return getForList(sql,cc.getName(),cc.getPassword());//调用DAO层中方法
}
4. A test may be implemented on this method
@Test
public void testGetListWithCriteriaCustomer(){
CriteriaCustomer criteriaCustomer = new CriteriaCustomer("Y",null);
List<Customer> customers = customerDAO.getListWithCirteriaCustomer(criteriaCustomer);
System.out.println(customers);
}
5. Modify Servlet, modified query method
private void query(HttpServletRequest req,HttpServletResponse resp){
String name = req.getParameter("name");
String password = req.getParameter("password");
CriteriaCustomer criteriaCustomer = new CriteriaCustomer(name,password);
List<Customer> list = customerDAO.getListWithCirteriaCustomer(criteriaCustomer);
req.setAttribute("list",list);
try {
req.getRequestDispatcher("/query.jsp").forward(req,resp);
} catch (ServletException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
effect:
