Mybatis将实体中数组元素转为JSON字符串存储

Mybatis将实体中数组元素转为JSON字符串存储

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.Data;
import org.apache.ibatis.type.JdbcType;
import org.util.JsonArrayTypeHandler;

import javax.validation.constraints.NotBlank;
import javax.validation.constraints.NotEmpty;


/**
 * 业务流程相关信息表
 * @author yangkaixiao
 * @since 2023-12-22
 */
@Data
@TableName(value = "entity", autoResultMap = true)
@ApiModel(value = "entity对象", description = "业务流程相关信息表")
public class Entity{

	/**
	 * ID
	 */
	@ApiModelProperty(value = "ID")
	@TableId(value = "id", type = IdType.ID_WORKER_STR)
	private String id;
	/**
	 * 相关业务ID，批量操作会出现多个ID
	 */
	@NotEmpty(message = "相关业务ID为空")
	@TableField(value = "relation_id", jdbcType = JdbcType.LONGNVARCHAR, typeHandler = JsonArrayTypeHandler.class)
	@ApiModelProperty(value = "相关业务ID")
	private String[] relationId;

	/**
	 * 相关业务数据
	 */
	@NotEmpty(message = "相关业务数据为空")
    @TableField(value = "relation_data", jdbcType = JdbcType.LONGNVARCHAR, typeHandler = JsonArrayTypeHandler.class)
	@ApiModelProperty(value = "相关业务数据")
	private Object[] relationData;
}

import cn.hutool.core.convert.ConvertException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.json.JsonMapper;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;

import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

/**
 * json数组类型转换器
 * @author yangkaixiao
 * @since 2023-12-22
 */
public class JsonArrayTypeHandler implements TypeHandler<Object[]> {

    private final Class<Object[]> valueType;

    public JsonArrayTypeHandler(Class<Object[]> valueType) {
        if (valueType == null) {
            throw new IllegalArgumentException("参数类型不能为空");
        }
        this.valueType = valueType;
    }

    @Override
    public void setParameter(PreparedStatement preparedStatement, int index, Object[] value, JdbcType jdbcType) throws SQLException {
        if (value == null) {
            preparedStatement.setNull(index, jdbcType.TYPE_CODE);
        } else {
            try {
                preparedStatement.setString(index, new JsonMapper().writeValueAsString(value));
            } catch (Exception e) {
                throw new ConvertException("对象数组转JSON字符串发生异常");
            }
        }
    }

    @Override
    public Object[] getResult(ResultSet resultSet, String columnName) throws SQLException {
        return this.convertValue(resultSet.getString(columnName));
    }

    @Override
    public Object[] getResult(ResultSet resultSet, int index) throws SQLException {
        return this.convertValue(resultSet.getString(index));
    }

    @Override
    public Object[] getResult(CallableStatement callableStatement, int index) throws SQLException {
        return this.convertValue(callableStatement.getString(index));
    }

    /**
     * 转换json字符串为对象数组
     * @param jsonValue json字符串
     * @return 对象数组
     */
    private Object[] convertValue(String jsonValue) {
        try {
            if (jsonValue == null) {
                return null;
            }
            return new ObjectMapper().readValue(jsonValue, valueType);
        } catch (Exception e) {
            throw new ConvertException("JSON字符串转对象数组发生异常");
        }
    }
}