controller:


byte[] blob = commonService.getPersonImage(bean.getIdCard());

String base64 = new String(blob));


service:

TableBean bean = getSqlSessionTemplate().selectOne("getPersonImage", idCard);
return bean.getBlob();


bean:

public Class tableBean {
private byte[] blob; //误区:不要用java.sql.Blob之类的
get..
set..
}


xml:

<select id="getPersonImage" parameterType="java.lang.String" resultType="tableBean">
SELECT blobColumn FROM tableName WHERE idCard=#{idCard,jdbcType=VARCHAR}
</select>


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