字符串属性转变List属性存入数据库

项目中有系统IP字段，现将string转List存入数据库，每个功能块持久层实现方法不一样(分为jpa和mp)

jpa：

 @Convert(converter = JpaConverterListJson.class)
    private List<String> hostIp;

public class JpaConverterListJson implements AttributeConverter<Object, String> {
    @Override
    public String convertToDatabaseColumn(Object o) {
        return JSON.toJSONString(o);
    }

    @Override
    public Object convertToEntityAttribute(String s) {
        //兼容历史数据
        if (!JSONUtil.isJson(s)) {
            return new JSONArray(Arrays.asList(s));
        }
        return JSON.parseArray(s);
    }

 ps:貌似@Lob也可以直接保存，没试过

 

mp:

@TableField(typeHandler = ArrayTypeHandler.class)
private List<String> hostIp;

@MappedTypes(List.class)
@MappedJdbcTypes(JdbcType.VARCHAR)
public class ArrayTypeHandler extends BaseTypeHandler<List> {

    @Override
    public void setNonNullParameter(PreparedStatement preparedStatement, int i, List list, JdbcType jdbcType) throws SQLException {
        preparedStatement.setString(i, JSON.toJSONString(list));
    }

    @Override
    public List getNullableResult(ResultSet resultSet, String s) throws SQLException {
        //兼容历史数据
        if (!JSONUtil.isJson(resultSet.getString(s))) {
            return new JSONArray(Arrays.asList(resultSet.getString(s)));
        }
        return JSON.parseArray(resultSet.getString(s));

    }

    @Override
    public List getNullableResult(ResultSet resultSet, int i) throws SQLException {
        JSONArray jsonArray = JSONArray.parseArray(resultSet.getString(i));
        return jsonArray;
    }

    @Override
    public List getNullableResult(CallableStatement callableStatement, int i) throws SQLException {
        JSONArray jsonArray = JSONArray.parseArray(callableStatement.getString(i));
        return jsonArray;
    }

//单这样查询获取不到，mp查询跟增改使用的ResultMap是不同的 //注解的typeHandler只生效于insert和update,要生效select必须@TableName(autoResultMap=true)
//但在自定义查询中添加了autoResultMap也没有用，还要在配置里加上map，查询结果指向它

<resultMap id="BaseResultMap" type="com.jk.cmdb.setting.entity.CmdbPc">
    <result column="host_ip" property="hostIp"
            typeHandler="com.jk.moinc.framework.ArrayTypeHandler"/>
</resultMap>

 

https://www.jianshu.com/p/1fbaff7fb187

https://github.com/baomidou/mybatis-plus/issues/357

 

jpa:

https://greenhtml.com/archives/153.html

https://blog.csdn.net/losfog/article/details/88046161

 

ps：如果是自定义的数组字段，是无法直接存入数据库也无法通过上述方式，那么存储转json字符串,取出转jsonArray