How to convert DTD to XSD with Ibatis sqlmap2

Question

I using Java 8 and Struts Framework. I want to convert from DTD to XSD, i.e. remove <!DOCTYPE..., in the sqlMapConfig.xml and sqlMap.xml files. However, there doesn't appear to be an alternative XSD file link for http://ibatis.apache.org/dtd/sql-map-2.dtd. Additionally, there is also a missing !DOCTYPE error. Is there any way to fix this?

sqlMapConfig.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMapConfig
        PUBLIC "-//ibatis.apache.org//DTD SQL Map Config 2.0//EN"
        "http://ibatis.apache.org/dtd/sql-map-config-2.dtd">

<sqlMapConfig>
    <settings useStatementNamespaces="true"/>

    <sqlMap resource="sql/sql.xml"/>
</sqlMapConfig>

sqlMap.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE sqlMap
        PUBLIC "-//ibatis.apache.org//DTD SQL Map 2.0//EN"
        "http://ibatis.apache.org/dtd/sql-map-2.dtd">

<sqlMap namespace="sql">

    <resultMap id="personMap" class="com.example.model.Person">
        <result property="name" column="name" />
        <result property="id" column="id" />
    </resultMap>

    <resultMap id="playerMap" class="com.example.model.Player">
        <result property="name" column="name" />
        <result property="id" column="player_id" />
        <result property="email" column="email" />
        <result property="password" column="password" />
        <result property="avatarUrl" column="avatar_url" />
    </resultMap>

    <resultMap id="matchMap" class="com.example.model.Match">
        <result property="id" column="match_id" />
        <result property="p1" column="p1_id" select="sql.getPlayerById" />
        <result property="p2" column="p2_id" select="sql.getPlayerById" />
        <result property="p1Score" column="p1_score" />
        <result property="p2Score" column="p2_score" />
        <result property="date" column="date" />
    </resultMap>

    <select id="getById" parameterClass="java.lang.String" resultMap="sql.personMap">
        select * from person where id = #id#
    </select>

    <select id="getPlayerById" parameterClass="java.lang.String" resultMap="sql.playerMap">
        select * from player where player_id = #id#
    </select>

    <select id="getPlayers"  resultMap="sql.playerMap">
        select * from player
    </select>

    <select id="getByEmail"  resultMap="sql.playerMap">
        select * from player where email = #email#
    </select>

    <select id="getByEmailAndPassword" parameterClass="java.util.Map" resultMap="sql.playerMap">
        select * from player where email = #email# and password = md5(#password#)
    </select>

    <insert id="insertRegistration" parameterClass="com.example.model.Player">
        insert into player
        (name, email, password, avatar_url)
        values
        (#name#, #email#, md5(#password#), #avatarUrl#)
        <selectKey resultClass="java.lang.String"  keyProperty="id">
            SELECT LAST_INSERT_ID()
        </selectKey>
    </insert>

    <insert id="insertMatch" parameterClass="com.example.model.Match">
        insert into matches
        (p1_id, p2_id, p1_score, p2_score, date)
        values
        (#p1.id#, #p2.id#, #p1Score#, #p2Score#, #date#)
        <selectKey resultClass="java.lang.String"  keyProperty="id">
            SELECT LAST_INSERT_ID()
        </selectKey>
    </insert>


    <select id="getMatchesByPlayer"  resultMap="sql.matchMap">
        select * from matches where p1_id = 1 OR  p2_id = #playerId#
    </select>

    <select id="getMatchesByPlayerByDateDesc"  resultMap="sql.matchMap">
        select * from matches where p1_id = #playerId# OR  p2_id = #playerId# order by date desc
    </select>

</sqlMap>

I have checked various sources and tried many methods, but most of the time I receive the following error:

Error processing XML. Cause: org.xml.sax.SAXParseException; lineNumber: 6; columnNumber: 76; Document root element "xs:schema" must match the DOCTYPE root "null".