MyBatis SQL statement mapping File (iii)----parameter passing

1. Single Basic type parameters (String,int, etc.)

A single primitive type parameter that parametertype the value of the corresponding statement to the same type as the parameter. Then use "#{parameter name}" to get

Java code

Parameter username of type string
public User finduser (String usernumber) {         return  (User) Sqlsessiontemplate.selectone ("Finduserbyusernumber", Usernumber);        }

XML code

Corresponds to Paramtertype= "string"
<id= "Finduserbyusernumber"  parametertype= "string"  Resulttype= "user">            select * from User where usernumber = #{usernumber}         </ Select >

2.Java Entity type parameters

Java entity type parameter: Sets the value of the ParameterType to the corresponding Java entity class, and then uses the property name of the #{class} to get

Java code

User entity class
publicvoid  updateUser (user user) {        sqlsessiontemplate.update ("UpdateUser", user);        } 

XML code

Point the ParameterType type to the specific address of the corresponding class (package name + class name), or to the alias (in the Mybatis.xml) file in Typealias
<id= "UpdateUser"  parametertype= "User">             update user set Username=#{username},loginname=#{loginname},loginpassword=#{loginpassword},sex=#{sex}, Birthday=#{birthday} where Usernumber=#{usernumber}        </update>

3. Multiple basic type parameters
In a specific business relationship, it is often necessary to pass multiple parameters, such as: Login-----> Username + password

 public   User Finduser (String loginname, String Loginpassword { //  TODO Auto-gene Rated method stub  map<string,string> map=new  hashmap<string, S        Tring> ();        Map.put ( "LoginName" , LoginName);        Map.put ( "Loginpassword" , Loginpassword);  return  (User) sqlsessiontemplate.selectone ("Loginuser" 

       <id= "Loginuser"  parametertype= "Map"  resulttype  = "User">            select * from User where loginname=#{loginname} and Loginpassword=#{loginpassword }        </Select>

One way to take advantage of Map knowledge multi-parameter transfer, there are other ways to achieve

　

MyBatis SQL statement mapping File (iii)----parameter passing