12_ Complex query 01_mapper proxy implementation

Engineering

"Code Implementation"

"User.java"

 Packagecom. Higgin.Mybatis.po;Importjava.util.Date; Public classUser {//property name corresponds to database table field        Private intID; PrivateString username; PrivateString sex; PrivateDate birthday; PrivateString address; //the corresponding get, set method}

"Usercustom.java"

 Package com. Higgin.Mybatis.po; /* information that can be used to extend a user */  Public class extends user{      // If you need to be able to increase the details              of the expansion here }

"Userqueryvo.java"

 Packagecom. Higgin.Mybatis.po;/*** Requirements: * Complete user information of the aggregate query, the need for incoming query conditions are complex (may also include user information, other information, such as goods, orders, etc.) * for the above requirements, we recommend that you use a custom wrapper type of Pojo * in the wrapper class to wrap the complex query conditions in*/ Public classUserqueryvo {//The required query conditions are packaged here//User Query Criteria    PrivateUsercustom Usercustom; This corresponds to the Usercustomer variable on the top. PublicUsercustom Getusercustom () {returnUsercustom; }     Public voidSetusercustom (Usercustom usercustom) { This. Usercustom =Usercustom; }}

"Usermapper.xml"//configuration is VERY important!!!!! , the namespace must correspond to the corresponding interface name:com. Higgin.Mybatis.mapper.UserMapper

 <Mappernamespace= "com. Higgin.Mybatis.mapper.UserMapper ">    <!--Comprehensive query for user information (complex query) #{usercustom.sex}: Remove the "gender" value from the Pojo wrapper object #{usercusotm.username}: Remove the user name from the Pojo wrapper class  -     <SelectID= "Finduserlist"ParameterType= "com. Higgin.Mybatis.po. Userqueryvo"Resulttype= "com. Higgin.Mybatis.po. usercustom">SELECT * from USER WHERE user.sex =#{usercustom.sex} and user.username like '%${usercustom.usern ame}% ' </Select> </Mapper>

"Usermapper.java" interface, methods in the Usermapper.java interface: method names in Finduserlist and Usermapper.xml are consistent

 Package com. Higgin.Mybatis.mapper; Import java.util.List; Import com. Higgin.Mybatis.po.User; Import com. Higgin.Mybatis.po.UserCustom; Import com. Higgin.Mybatis.po.UserQueryVo;  Public Interface usermapper {        // User Information Comprehensive query finduserlistpublic    throws Exception;
}

"Sqlmappercongfg.xml"//Add a load file, this file will be loaded in the test class

<!---    <mappers>        <  Resource = "Sqlmap/user.xml" />        <  resource= "Mapper/usermapper.xml"/>    </  Mappers>

"Usermappertest.java"//test class

 Public classUsermappertest {Privatesqlsessionfactory sqlsessionfactory; @Before Public voidSetUp ()throwsException {//Create Sqlsessionfactory//mybatis configuration fileString resource= "Sqlmapconfig.xml"; //get configuration file streamInputStream inputstream=Resources.getresourceasstream (Resource); //creating a session factory, passing in MyBatis profile informationsqlsessionfactory=NewSqlsessionfactorybuilder (). Build (InputStream); }/*** Comprehensive complex query of user information *@throwsException*/@Test Public voidTestfinduserlist ()throwsException {sqlsession sqlsession=sqlsessionfactory.opensession (); //creates a Usermapper object that MyBatis automatically generates mapper proxy objectsUsermapper Usermapper=sqlsession.getmapper (Usermapper.class); //Create wrapper objects, set query criteriaUserqueryvo userqueryvo=NewUserqueryvo (); Usercustom Usercustom=NewUsercustom (); Usercustom.setsex ("1"); Usercustom.setusername ("6");                Userqueryvo.setusercustom (Usercustom); //methods for calling UsermapperList<usercustom> list=usermapper.finduserlist (USERQUERYVO);    System.out.println (List.size ()); }}

"Run Results"

"Debug list data, all genders are" 1 ", Username contains" 6 "Data sets"

12_ Complex query 01_mapper proxy implementation