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package com.example.demo.handler;import com.example.demo.common.BaseIntEnum;import org.apache.ibatis.type.BaseTypeHandler;import org.apache.ibatis.type.JdbcType;import org.apache.ibatis.type.MappedJdbcTypes;import org.apache.ibatis.type.MappedTypes;import java.sql.*;/** * @Author lyr * @create 2020/12/19 20:48 */@MappedJdbcTypes(JdbcType.INTEGER)@MappedTypes(BaseIntEnum.class)// @Componentpublic  class BaseEnumTypeHandler
   
     extends BaseTypeHandler
    
      {
       /**     * 枚举数组的 类     */    private final Class
     
       enumClazz;    /**     * 枚举数组     */    private final E[] values;    /**     * 遇到空对象是否设置默认值     */    private E defaultEnum;    private E codeOf(int code) {
           for (E e : values) {
               if (e.getValue() == code) {
                   return e;            }        }        return null;    }    public BaseEnumTypeHandler(Class
      
        enumClazz) {
           if (enumClazz == null) {
               throw new IllegalArgumentException("base enum TypeHandler enum class cannot be null !@!!!");        }        this.enumClazz = enumClazz;        values = enumClazz.getEnumConstants();        if (values!=null && values.length>0) {
               defaultEnum = (E)values[0].getValueWhenObjectFieldNull();            // System.out.println(defaultEnum);        }    }    @Override    public void setNonNullParameter(PreparedStatement preparedStatement, int i, E e, JdbcType jdbcType) throws SQLException {
           // preparedStatement.set        preparedStatement.setInt(i, e.getValue());    }    @Override    public void setParameter(PreparedStatement ps, int i, E parameter, JdbcType jdbcType) throws SQLException {
           if (parameter==null)            parameter = defaultEnum;        super.setParameter(ps, i, parameter, jdbcType);    }    /**     * 可以空的对象     *     * @param resultSet     * @param s     * @return     * @throws SQLException     */    @Override    public E getNullableResult(ResultSet resultSet, String s) throws SQLException {
           int code = resultSet.getInt(s);        return resultSet.wasNull() ? defaultEnum : codeOf(code);    }    @Override    public E getNullableResult(ResultSet resultSet, int i) throws SQLException {
           int code = resultSet.getInt(i);        return resultSet.wasNull() ? defaultEnum : codeOf(code);    }    @Override    public E getNullableResult(CallableStatement callableStatement, int i) throws SQLException {
           int code = callableStatement.getInt(i);        return callableStatement.wasNull() ? defaultEnum : codeOf(code);    }}
      
     
    
   

通用枚举接口

package com.example.demo.common;/** * @Author lyr * @create 2020/12/19 20:37 */public interface BaseIntEnum
   
    > {
       /**     * 存入数据库的值     * @return     */    int getValue();    /**     * 当遇到 field 为 null 对象时候，是否设置默认值     * @return     */    E getValueWhenObjectFieldNull();    /**     * @return 打印的名字     */    String getDisplayName();}
   

例子：

package com.example.demo.common;import lombok.AllArgsConstructor;import lombok.Getter;import lombok.ToString;/** * @Author lyr * @create 2020/12/19 20:37 */@AllArgsConstructor@Getter@ToStringpublic enum SexIntEnum implements BaseIntEnum
   
     {
       MAN(1,"男"),    GIRL(0,"女生"),    UNKNOWN(-1,"人妖");    private Integer code;    private String message;    /**     * 存入数据库的值     *     * @return     */    @Override    public int getValue() {
           return code;    }    /**     * 当遇到 null 对象时候，是否设置默认值     *     * @return     */    @Override    public SexIntEnum getValueWhenObjectFieldNull() {
           return UNKNOWN;    }    /**     * @return 打印的名字     */    @Override    public String getDisplayName() {
           return toString();    }}
   

配置

yml demo

mybatis:  mapper-locations: classpath:/mapper/**/*.xml  type-aliases-package: com.example.demo.pojo  configuration:    map-underscore-to-camel-case: true  type-handlers-package: com.example.demo.handler.BaseEnumTypeHandler

Junit demo

@Resource    private StudentMapper studentMapper;    @Test    void iiiii() {
           studentMapper.insert(new Student());    }

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