MyBatis 無論是 resultType 還是 resultMap 都需要一個(gè)實(shí)體例如我們這樣一個(gè)SQL<mapper namespace="com.savorgames.dao.MemberMapper">   <select id="test" resultType="com.savorgames.domain.Member">       SELECT username,password FROM "user";  </select></mapper>Member實(shí)體public class Member {        private int uid;    private String username;    private String password;    private String email;    private String nickname;        public int getUid() {        return uid;    }    public void setUid(int uid) {        this.uid = uid;    }    public String getUsername() {        return username;    }    public void setUsername(String username) {        this.username = username;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    public String getEmail() {        return email;    }    public void setEmail(String email) {        this.email = email;    }    public String getNickname() {        return nickname;    }    public void setNickname(String nickname) {        this.nickname = nickname;    }}結(jié)果集映射MapperList<Member>現(xiàn)在問題來了，做restful服務(wù)器時(shí)候，將實(shí)體轉(zhuǎn)換成 json 會(huì)出現(xiàn)大量空值 并暴露數(shù)據(jù)庫表字段，傳輸?shù)膉son也相對(duì)變大了例如：[{"uid":0,"username":"阿斯達(dá)","password":null,"email":null,"nickname":null},{"uid":0,"username":"阿薩法","password":null,"email":null,"nickname":null},{"uid":0,"username":"阿斯達(dá)","password":null,"email":null,"nickname":null},{"uid":0,"username":"啊實(shí)打?qū)嵉?quot;,"password":null,"email":null,"nickname":null},{"uid":0,"username":"阿斯達(dá)啊","password":null,"email":null,"nickname":null},{"uid":0,"username":"是打算打","password":null,"email":null,"nickname":null},{"uid":0,"username":"阿斯達(dá)","password":"12312312","email":null,"nickname":null}]總不能每一個(gè)sql語句都寫一個(gè)實(shí)體類吧，如何靈活的處理 MyBatis 結(jié)果集，只返回查詢字段？