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文章目录
- ObjectMapperUtil
ObjectMapperUtil
import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.SerializationFeature;
import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;import java.io.IOException;
import java.util.Map;/*** bean 映射工具类*/
@Slf4j
public final class ObjectMapperUtil {private static ObjectMapper objectMapper = new ObjectMapper();static {objectMapper.registerModule(new JavaTimeModule())// 是否需要排序.configure(SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS, true)// 忽略空bean转json的错误.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false)// 取消默认转换timestamps形式.configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false)// 序列化的时候，过滤null属性.setSerializationInclusion(Include.NON_NULL)// 忽略在json字符串中存在，但在java对象中不存在对应属性的情况，防止错误.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES)// 忽略空bean转json的错误.disable(SerializationFeature.FAIL_ON_EMPTY_BEANS)// the parameter WRITE_DATES_AS_TIMESTAMPS tells the mapper to represent a Date as a String in JSON.disable(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS);}private ObjectMapperUtil() {}/*** 对象转json字符串** @param obj 对象* @param <T> 对象泛型* @return json字符串*/public static <T> String obj2Json(T obj) {if (obj == null) {return null;}try {return obj instanceof String ? (String) obj : objectMapper.writeValueAsString(obj);} catch (Exception e) {log.warn("对象解析为json字符串异常", e);}return null;}/*** Obj转Map* @param obj 对象* @param <T> 对象泛型* @return Map集合*/public static <T> Map obj2Map(T obj) {if (obj == null) {return null;}try {return objectMapper.readValue(obj2Json(obj),Map.class);} catch (Exception e) {log.warn("对象解析为Map异常", e);}return null;}/*** 对象转bytes** @param obj 对象* @param <T> 对象泛型* @return json字符串*/public static <T> byte[] obj2Bytes(T obj) {if (obj == null) {return null;}try {return objectMapper.writeValueAsBytes(obj);} catch (Exception e) {log.warn("对象解析为byte数组异常", e);}return null;}/*** 对象转json字符串，并进行格式化** @param obj 对象* @param <T> 对象泛型* @return 格式化后的json字符串*/public static <T> String obj2JsonPretty(T obj) {if (obj == null) {return null;}try {return obj instanceof String ? (String) obj : objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(obj);} catch (Exception e) {log.warn("对象解析为json字符串异常", e);}return null;}/*** json转对象* 这里有一个坑，例如List<User> list = stringObj(str,Class<List> data);这里会有问题** @param jsonStr json字符串* @param clazz 对象* @param <T> 对象泛型* @return 反序列化后的对象*/public static <T> T str2Obj(String jsonStr, Class<T> clazz) {if (StringUtils.isBlank(jsonStr) || null == clazz) {return null;}try {return clazz.equals(String.class) ? (T) jsonStr : objectMapper.readValue(jsonStr, clazz);} catch (Exception e) {log.warn("json字符串解析为对象异常", e);return null;}}/*** 复杂对象反序列化* 使用例子List<User> list = JsonUtil.string2Obj(str, new TypeReference<List<User>>() {});** @param str json对象* @param typeReference 引用类型* @param <T> 返回值类型* @return 反序列化对象*/public static <T> T str2Obj(String str, TypeReference<T> typeReference) {if (StringUtils.isBlank(str) || typeReference == null) {return null;}try {return (T) (typeReference.getType().equals(String.class) ? str : objectMapper.readValue(str, typeReference));} catch (IOException e) {log.warn("json字符串解析为对象错误", e);return null;}}/*** 复杂对象反序列化* 使用例子List<User> list = JsonUtil.string2Obj(str, List.class, User.class);** @param str json对象* @param collectionClass 定义的class类型* @param elementClass 子元素的class类型* @param <T> 返回值类型* @return 反序列化对象*/public static <T> T str2Obj(String str, Class<?> collectionClass, Class<?>... elementClass) {JavaType javaType = objectMapper.getTypeFactory().constructParametricType(collectionClass, elementClass);try {return objectMapper.readValue(str, javaType);} catch (IOException e) {log.warn("json字符串解析为对象错误", e);return null;}}/*** 对象转换 && 对象深复制** @param obj 源对象* @param clazz 目标对象引用类型* @param <T> 返回值类型* @return T*/public static <T> T convert(Object obj, TypeReference<T> clazz) {try {return objectMapper.convertValue(obj, clazz);} catch (Exception e) {log.warn("对象转换异常", e);}return null;}/*** 对象转换 && 对象深复制** @param obj 源对象* @param clazz 目标对象类型* @param <T> 返回值类型* @return T*/public static <T> T convert(Object obj, Class<T> clazz) {try {return objectMapper.convertValue(obj, clazz);} catch (Exception e) {log.warn("对象转换异常", e);}return null;}/*** 对象转bytes** @param obj 对象* @param <T> 对象泛型* @return 字节数组*/public static <T> byte[] objToBytes(T obj) {if (obj == null) {return null;}try {return objectMapper.writeValueAsBytes(obj);} catch (Exception e) {log.warn("对象解析为byte数组异常", e);}return null;}}
