1. 参考mybatis-plus
mybatis Java对象、list和json转换 网上好多不靠谱,参考mybatis-plus中@TableField,mybatis中自定义实现
这样不需要对象中属性字符串接收,保存到表中,都是转义字符,使用时还要手动转换为对象或者List
使用时直接添加注解,比较方便//对象,也可以JSONObject@TableOperateField(typeHandler = JacksonTypeHandler.class)private SysWarnNotesysWarnNote;//List,泛型也可以是Object,,这样比较随便了@TableOperateField(typeHandler = JacksonListTypeHandler.class)private List<SysWarnNote> sysWarnNote;
2. 仿照mybatis-plus自定义注解TableOperateField
package com.yl.cache.annotation;import org.apache.ibatis.type.TypeHandler;
import org.apache.ibatis.type.UnknownTypeHandler;import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** TableOperateField注解,用于mybatis insert或者update表时自动给字段赋值* <p>使用方法* <pre>* @TableOperateField(value=TableOperateField.OperateType.Insert)* private Date createTime;* </pre>** @author liuxubo* @date 2023/7/23 14:39*/
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.FIELD})
public @interface TableOperateField {/*** 操作字段类型** @return*/OperateType value() default OperateType.None;/*** 类型处理器 (该默认值不代表会按照该值生效)* @return*/Class<? extends TypeHandler> typeHandler() default UnknownTypeHandler.class;/*** 操作sql类型*/public enum OperateType {None,Insert,Delete,Update,Select,InsertOrUpdate,;}}
3. 新增、修改日期自动填充
新增、修改时,创建时间和修改时间,手动填充不优雅,使用数据库默认值时间会和系统时间不一致情况 ,这里模仿mybatis-plus实现
package com.yl.cache.interceptor;import com.yl.cache.annotation.TableOperateField;
import com.yl.cache.annotation.TableOperateField.OperateType;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.SqlCommandType;
import org.apache.ibatis.plugin.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Plugin;
import org.apache.ibatis.plugin.Signature;
import org.springframework.stereotype.Component;import java.lang.reflect.Field;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.Date;
import java.util.Properties;/*** 表字段自动填充值拦截类** @author liuxubo* @date 2023/7/23 14:56*/
@Slf4j
@Component //使用 mybatis-spring-boot-starter 会自动注入 识别 mybatis的Interceptor 接口实现类
@Intercepts({@Signature(type = org.apache.ibatis.executor.Executor.class, method = "update", args = {MappedStatement.class, Object.class})})
public class TableOperateInterceptor implements Interceptor {@Overridepublic Object intercept(Invocation invocation) throws Throwable {MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0];// 获取 SQL 命令SqlCommandType sqlCommandType = mappedStatement.getSqlCommandType();
// log.info("{}", sqlCommandType);// 获取参数Object parameter = invocation.getArgs()[1];// 获取私有成员变量Field[] declaredFields = parameter.getClass().getDeclaredFields();if (parameter.getClass().getSuperclass() != null) {Field[] superField = parameter.getClass().getSuperclass().getDeclaredFields();declaredFields = ArrayUtils.addAll(declaredFields, superField);}for (Field field : declaredFields) {TableOperateField tableOperateField = field.getAnnotation(TableOperateField.class);if (tableOperateField == null) {continue;}// insertif (tableOperateField.value().equals(TableOperateField.OperateType.Insert) || tableOperateField.value().equals(OperateType.InsertOrUpdate)) {if (SqlCommandType.INSERT.equals(sqlCommandType)) {setFieldDateValue(parameter, field);}}// updateif (tableOperateField.value().equals(TableOperateField.OperateType.Update) || tableOperateField.value().equals(TableOperateField.OperateType.InsertOrUpdate)) {if (SqlCommandType.UPDATE.equals(sqlCommandType)) {field.setAccessible(true);setFieldDateValue(parameter, field);}}}return invocation.proceed();}/*** 设置时间值** @param parameter bean对象* @param field field对象* @throws IllegalAccessException*/private static void setFieldDateValue(Object parameter, Field field) throws IllegalAccessException {field.setAccessible(true);if (field.getType().equals(LocalDateTime.class)) {field.set(parameter, LocalDateTime.now());} else if (field.getType().equals(LocalDate.class)) {field.set(parameter, LocalDate.now());} else {field.set(parameter, new Date());}}/*** 生成MyBatis拦截器代理对象*/@Overridepublic Object plugin(Object target) {if (target instanceof org.apache.ibatis.executor.Executor) {return Plugin.wrap(target, this);}return target;}/*** 设置插件属性(直接通过Spring的方式获取属性,所以这个方法一般也用不到)* 项目启动的时候数据就会被加载*/@Overridepublic void setProperties(Properties properties) {}
}
4. 测试新增、修改日期自动填充
@Data
public class User {/*** 创建时间*/@TableOperateField(value = TableOperateField.OperateType.Insert)private LocalDateTime createTime;/*** 更新时间*/@TableOperateField(value = OperateType.InsertOrUpdate)private LocalDateTime updateTime;
}
5. Java实体类、List和表中json转换处理器
package com.yl.cache.handler;import org.apache.commons.lang3.StringUtils;
import org.apache.ibatis.type.BaseTypeHandler;
import org.apache.ibatis.type.JdbcType;import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;/*** mybatis-plus 内置 AbstractJsonTypeHandler** @author liuxubo* @date 2023/8/1 0:08*/
public abstract class AbstractJsonTypeHandler<T> extends BaseTypeHandler<T> {@Overridepublic void setNonNullParameter(PreparedStatement ps, int i, T parameter, JdbcType jdbcType) throws SQLException {ps.setString(i, toJson(parameter));}@Overridepublic T getNullableResult(ResultSet rs, String columnName) throws SQLException {final String json = rs.getString(columnName);return StringUtils.isBlank(json) ? null : parse(json);}@Overridepublic T getNullableResult(ResultSet rs, int columnIndex) throws SQLException {final String json = rs.getString(columnIndex);return StringUtils.isBlank(json) ? null : parse(json);}@Overridepublic T getNullableResult(CallableStatement cs, int columnIndex) throws SQLException {final String json = cs.getString(columnIndex);return StringUtils.isBlank(json) ? null : parse(json);}/*** 将表中字段值为json字符串解析为Java对象** @param json 表中字段值为json字符串* @return:T*/protected abstract T parse(String json);/*** 将Java对象序列化为json字符串保存到表中** @param obj Java对象* @return:java.lang.String*/protected abstract String toJson(T obj);
}
package com.yl.cache.handler;import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.yl.cache.annotation.TableOperateField;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;/*** Jackson 实现 JSON 字段类型处理器* <p> List、Map、自定义对象,转换为json字符串存储到数据库,查询出来的时候自动转换为相应的对象** @author hubin* @since 2019-08-25*/
@Slf4j
@MappedTypes({Object.class})
@MappedJdbcTypes({JdbcType.VARCHAR, JdbcType.CHAR, JdbcType.NCHAR, JdbcType.LONGVARCHAR})
public class JacksonTypeHandler extends AbstractJsonTypeHandler<Object> {private static ObjectMapper OBJECT_MAPPER;private final Class<?> type;/*** 构造函数** @param type 指定类型* @date:2023/7/31 17:52*/public JacksonTypeHandler(Class<?> type) {if (log.isTraceEnabled()) {log.trace("JacksonTypeHandler(" + type + ")");}Objects.requireNonNull(type, "Type argument cannot be null");this.type = type;}@Overrideprotected Object parse(String json) {try {return getObjectMapper().readValue(json, type);} catch (IOException e) {throw new RuntimeException(e);}}@Overrideprotected String toJson(Object obj) {try {return getObjectMapper().writeValueAsString(obj);} catch (JsonProcessingException e) {throw new RuntimeException(e);}}public static ObjectMapper getObjectMapper() {if (null == OBJECT_MAPPER) {OBJECT_MAPPER = new ObjectMapper();}return OBJECT_MAPPER;}public static void setObjectMapper(ObjectMapper objectMapper) {Objects.requireNonNull(objectMapper, "ObjectMapper should not be null");JacksonTypeHandler.OBJECT_MAPPER = objectMapper;}/*** 查找实体类中含有注解 @TableOperateField(typeHandler = JacksonTypeHandler.class) 的字段** @param clazz class* @return 实体类中含有注解 @TableOperateField(typeHandler = JacksonTypeHandler.class) 的字段列表*/public static List<Type> findJsonValueFieldName(Class<?> clazz) {if (clazz != null) {return Arrays.stream(clazz.getDeclaredFields()).filter(field -> field.isAnnotationPresent(TableOperateField.class)&& JacksonTypeHandler.class.isAssignableFrom(field.getAnnotation(TableOperateField.class).typeHandler())).map(Field::getGenericType).collect(Collectors.toList());}return Collections.EMPTY_LIST;}}package com.yl.cache.handler;import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.yl.cache.annotation.TableOperateField;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;import java.io.IOException;
import java.lang.reflect.Field;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;/*** Jackson 实现 JSON 字段类型处理器* <p> List、Map、自定义对象,转换为json字符串存储到数据库,查询出来的时候自动转换为相应的对象** @author hubin* @since 2019-08-25*/
@Slf4j
@MappedTypes({List.class})
@MappedJdbcTypes({JdbcType.VARCHAR, JdbcType.CHAR, JdbcType.NCHAR, JdbcType.LONGVARCHAR})
public class JacksonListTypeHandler extends AbstractJsonTypeHandler<List<Object>> {private static ObjectMapper OBJECT_MAPPER;private final Class<?> type;/*** 构造函数** @param type 指定类型* @date:2023/7/31 17:52*/public JacksonListTypeHandler(Class<?> type) {if (log.isTraceEnabled()) {log.trace("JacksonTypeHandler(" + type + ")");}Objects.requireNonNull(type, "Type argument cannot be null");this.type = type;}@Overrideprotected List<Object> parse(String json) {try {return getObjectMapper().readValue(json, List.class);} catch (IOException e) {throw new RuntimeException(e);}}@Overrideprotected String toJson(List<Object> obj) {try {return getObjectMapper().writeValueAsString(obj);} catch (JsonProcessingException e) {throw new RuntimeException(e);}}public static ObjectMapper getObjectMapper() {if (null == OBJECT_MAPPER) {OBJECT_MAPPER = new ObjectMapper();}return OBJECT_MAPPER;}public static void setObjectMapper(ObjectMapper objectMapper) {Objects.requireNonNull(objectMapper, "ObjectMapper should not be null");JacksonListTypeHandler.OBJECT_MAPPER = objectMapper;}/*** 查找实体类中含有注解 @TableOperateField(typeHandler = JacksonTypeHandler.class) 的字段** @param clazz class* @return 实体类中含有注解 @TableOperateField(typeHandler = JacksonTypeHandler.class) 的字段列表*/public static List<Type> findJsonValueFieldName(Class<?> clazz) {if (clazz != null) {return Arrays.stream(clazz.getDeclaredFields()).filter(field -> field.isAnnotationPresent(TableOperateField.class)&& JacksonListTypeHandler.class.isAssignableFrom(field.getAnnotation(TableOperateField.class).typeHandler())).map(Field::getGenericType).collect(Collectors.toList());}return Collections.EMPTY_LIST;}}
package com.yl.cache.handler;import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature;
import com.yl.cache.annotation.TableOperateField;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.MappedJdbcTypes;
import org.apache.ibatis.type.MappedTypes;import java.lang.reflect.Field;
import java.lang.reflect.Type;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;/*** Fastjson 实现 JSON 字段类型处理器** @author hubin* @since 2019-08-25*/
@Slf4j
@MappedTypes({Object.class})
@MappedJdbcTypes({JdbcType.VARCHAR, JdbcType.CHAR, JdbcType.NCHAR, JdbcType.LONGVARCHAR})
public class FastjsonTypeHandler extends AbstractJsonTypeHandler<Object> {private final Class<?> type;public FastjsonTypeHandler(Class<?> type) {if (log.isTraceEnabled()) {log.trace("FastjsonTypeHandler(" + type + ")");}Objects.requireNonNull(type, "Type argument cannot be null");this.type = type;}@Overrideprotected Object parse(String json) {return JSON.parseObject(json, type);}@Overrideprotected String toJson(Object obj) {return JSON.toJSONString(obj, SerializerFeature.WriteMapNullValue,SerializerFeature.WriteNullListAsEmpty, SerializerFeature.WriteNullStringAsEmpty);}/*** 查找实体类中含有注解 @TableOperateField(typeHandler = FastjsonTypeHandler.class) 的字段** @param clazz class* @return EnumValue字段*/public static List<Type> findJsonValueFieldName(Class<?> clazz) {if (clazz != null) {return Arrays.stream(clazz.getDeclaredFields()).filter(field -> field.isAnnotationPresent(TableOperateField.class)&& FastjsonTypeHandler.class.isAssignableFrom(field.getAnnotation(TableOperateField.class).typeHandler())).map(Field::getGenericType).collect(Collectors.toList());}return Collections.EMPTY_LIST;}
}
6. 注册处理类
自定义配置扫描包type-json-package,指定扫描范围
mybatis:mapper-locations: classpath:mappers/*.xmltype-aliases-package: com.yl.cache.entityconfiguration:map-underscore-to-camel-case: truetype-json-package: com.yl.cache.entity
配置类
package com.yl.cache.config;import com.yl.cache.handler.FastjsonTypeHandler;
import com.yl.cache.handler.JacksonListTypeHandler;
import com.yl.cache.handler.JacksonTypeHandler;
import lombok.extern.slf4j.Slf4j;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandlerRegistry;
import org.mybatis.spring.boot.autoconfigure.ConfigurationCustomizer;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.type.ClassMetadata;
import org.springframework.core.type.classreading.CachingMetadataReaderFactory;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;
import sun.reflect.generics.reflectiveObjects.ParameterizedTypeImpl;import java.io.IOException;
import java.lang.reflect.Type;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;
import java.util.stream.Collectors;/*** MyBatis配置自定义 typeHandler 推荐实现ConfigurationCustomizer接口配置方式** @author liuxb* @date 2021/12/19 18:17*/
@Slf4j
@org.springframework.context.annotation.Configuration
public class CommonMyBatisConfig implements ConfigurationCustomizer {private static final ResourcePatternResolver RESOURCE_PATTERN_RESOLVER = new PathMatchingResourcePatternResolver();private static final MetadataReaderFactory METADATA_READER_FACTORY = new CachingMetadataReaderFactory();@Value("${mybatis.type-json-package:}")private String typeJsonPackage;@Overridepublic void customize(Configuration configuration) {// 设置null也返回configuration.setCallSettersOnNulls(true);// 设置一行都为null也返回configuration.setReturnInstanceForEmptyRow(true);configuration.setJdbcTypeForNull(JdbcType.NULL);TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry();//如果给定扫描json类包,注册类名为属性含有 @TableOperateField(typeHandler = JacksonTypeHandler.class)的实体类if (StringUtils.hasLength(typeJsonPackage)) {Set<Class<?>> classes = scanClasses(typeJsonPackage, null);if (classes.isEmpty()) {log.warn("Can't find class in '[" + typeJsonPackage + "]' package. Please check your configuration.");return;}Set<Type> jacksonTypes = classes.stream().map(cls -> JacksonTypeHandler.findJsonValueFieldName(cls)).flatMap(types -> types.stream()).collect(Collectors.toSet());registerTypeHandler(typeHandlerRegistry, jacksonTypes, JacksonTypeHandler.class);Set<Type> fastJsonTypes = classes.stream().map(cls -> FastjsonTypeHandler.findJsonValueFieldName(cls)).flatMap(types -> types.stream()).collect(Collectors.toSet());registerTypeHandler(typeHandlerRegistry, fastJsonTypes, FastjsonTypeHandler.class);Set<Type> jacksonListTypes = classes.stream().map(cls -> JacksonListTypeHandler.findJsonValueFieldName(cls)).flatMap(types -> types.stream()).collect(Collectors.toSet());registerTypeHandler(typeHandlerRegistry, jacksonListTypes, JacksonListTypeHandler.class);}}/*** 注册自定义类型处理器** @param typeHandlerRegistry* @param types 类型*/private void registerTypeHandler(TypeHandlerRegistry typeHandlerRegistry, Set<Type> types, Class typeHandlerClass) {if (!types.isEmpty()) {log.info("mybatis register json type handler {}", types);types.forEach(type -> {//集合类String typeName = type.getTypeName();if(typeName.contains("java.util.List<") && typeName.endsWith(">")){Class<?> rawType = ((ParameterizedTypeImpl) type).getRawType();typeHandlerRegistry.register(rawType, typeHandlerClass);}else{//实体类Class<?> clazz = (Class<?>) type;if (org.apache.commons.lang3.ClassUtils.isPrimitiveOrWrapper(clazz) || String.class.equals(clazz)) {throw new RuntimeException("请检查@TableOperateField(typeHandler = JacksonTypeHandler.class)标记的属性类型");}typeHandlerRegistry.register(clazz, typeHandlerClass);}});}}/*** 根据包路径和指定类的子类,获取当前包和子包下的全部类** @param packagePatterns 指定包* @param assignableType 父类* @return*/private Set<Class<?>> scanClasses(String packagePatterns, Class<?> assignableType) {Set<Class<?>> classes = new HashSet<>();try {String[] packagePatternArray = StringUtils.tokenizeToStringArray(packagePatterns, ConfigurableApplicationContext.CONFIG_LOCATION_DELIMITERS);for (String packagePattern : packagePatternArray) {Resource[] resources = RESOURCE_PATTERN_RESOLVER.getResources(ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX+ ClassUtils.convertClassNameToResourcePath(packagePattern) + "/**/*.class");for (Resource resource : resources) {try {ClassMetadata classMetadata = METADATA_READER_FACTORY.getMetadataReader(resource).getClassMetadata();Class<?> clazz = Resources.classForName(classMetadata.getClassName());if (assignableType == null || assignableType.isAssignableFrom(clazz)) {classes.add(clazz);}} catch (Throwable e) {log.warn("Cannot load the '" + resource + "'. Cause by " + e.toString());}}}} catch (IOException e) {log.warn("scan " + packagePatterns + ", io error");}return classes;}}
7. 测试 保证增删改查接口都能正常
CREATE TABLE `user` (`id` int NOT NULL AUTO_INCREMENT COMMENT '主键id(自增)',`sys_warn_note` varchar(100) DEFAULT NULL COMMENT '系统告警信息',`create_time` datetime NOT NULL,`update_time` datetime NOT NULL COMMENT '更新时间',PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='测试用户表'上送json字符串,JSONObject 接收,表字段为varchar,text,json类型都可以,使用mysql8
http://localhost:8080/jobWarnMessage/add
{"code": "006","sysWarnNote": {"address": "北京大雨了"}}
@Data
public class User{@TableOperateField(typeHandler = JacksonTypeHandler.class)private JSONObject sysWarnNote;
}
也可以为List
@Data
public class SysWarnNote {private String name;private String content;
}
@Data
public class User{@TableOperateField(typeHandler = JacksonListTypeHandler.class)private List<SysWarnNote> sysWarnNote;
}