JsonUtil ?jakson工具类

package com.mmall.util;import com.google.common.collect.Lists;import com.mmall.pojo.Category;import com.mmall.pojo.TestPojo;import com.mmall.pojo.User;import lombok.extern.slf4j.Slf4j;import org.apache.commons.lang.StringUtils;import org.codehaus.jackson.map.DeserializationConfig;import org.codehaus.jackson.map.ObjectMapper;import org.codehaus.jackson.map.SerializationConfig;import org.codehaus.jackson.map.annotate.JsonSerialize.Inclusion;import org.codehaus.jackson.type.JavaType;import org.codehaus.jackson.type.TypeReference;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Date;import java.util.HashMap;import java.util.List;import java.util.Map;/** * Created by geely */@Slf4jpublic class JsonUtil { ???private static ObjectMapper objectMapper = new ObjectMapper(); ???static{ ???????//对象的所有字段全部列入 ???????objectMapper.setSerializationInclusion(Inclusion.ALWAYS); ???????//取消默认转换timestamps形式 ???????objectMapper.configure(SerializationConfig.Feature.WRITE_DATES_AS_TIMESTAMPS,false); ???????//忽略空Bean转json的错误 ???????objectMapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS,false); ???????//所有的日期格式都统一为以下的样式，即yyyy-MM-dd HH:mm:ss ???????objectMapper.setDateFormat(new SimpleDateFormat(DateTimeUtil.STANDARD_FORMAT)); ???????//忽略 在json字符串中存在，但是在java对象中不存在对应属性的情况。防止错误 ???????objectMapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES,false); ???} ???public static <T> String obj2String(T obj){ ???????if(obj == null){ ???????????return null; ???????} ???????try { ???????????return obj instanceof String ? (String)obj : ?objectMapper.writeValueAsString(obj); ???????} catch (Exception e) { ???????????log.warn("Parse Object to String error",e); ???????????return null; ???????} ???} ???public static <T> String obj2StringPretty(T obj){ ???????if(obj == null){ ???????????return null; ???????} ???????try { ???????????return obj instanceof String ? (String)obj : ?objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(obj); ???????} catch (Exception e) { ???????????log.warn("Parse Object to String error",e); ???????????return null; ???????} ???} ???public static <T> T string2Obj(String str,Class<T> clazz){ ???????if(StringUtils.isEmpty(str) || clazz == null){ ???????????return null; ???????} ???????try { ???????????return clazz.equals(String.class)? (T)str : objectMapper.readValue(str,clazz); ???????} catch (Exception e) { ???????????log.warn("Parse String to Object error",e); ???????????return null; ???????} ???} ???public static <T> T string2Obj(String str, TypeReference<T> typeReference){ ???????if(StringUtils.isEmpty(str) || typeReference == null){ ???????????return null; ???????} ???????try { ???????????return (T)(typeReference.getType().equals(String.class)? str : objectMapper.readValue(str,typeReference)); ???????} catch (Exception e) { ???????????log.warn("Parse String to Object error",e); ???????????return null; ???????} ???} ???public static <T> T string2Obj(String str,Class<?> collectionClass,Class<?>... elementClasses){ ???????JavaType javaType = objectMapper.getTypeFactory().constructParametricType(collectionClass,elementClasses); ???????try { ???????????return objectMapper.readValue(str,javaType); ???????} catch (Exception e) { ???????????log.warn("Parse String to Object error",e); ???????????return null; ???????} ???} ???public static void main(String[] args) { ???????TestPojo testPojo = new TestPojo(); ???????testPojo.setName("Geely"); ???????testPojo.setId(666); ???????//{"name":"Geely","id":666} ???????String json = "{\"name\":\"Geely\",\"color\":\"blue\",\"id\":666}"; ???????TestPojo testPojoObject = JsonUtil.string2Obj(json,TestPojo.class);// ???????String testPojoJson = JsonUtil.obj2String(testPojo);// ???????log.info("testPojoJson:{}",testPojoJson); ???????log.info("end");// ???????User user = new User();// ???????user.setId(2);// ???????user.setEmail("geely@happymmall.com");// ???????user.setCreateTime(new Date());// ???????String userJsonPretty = JsonUtil.obj2StringPretty(user);// ???????log.info("userJson:{}",userJsonPretty);// ???????User u2 = new User();// ???????u2.setId(2);// ???????u2.setEmail("geelyu2@happymmall.com");//////// ???????String user1Json = JsonUtil.obj2String(u1);//// ???????String user1JsonPretty = JsonUtil.obj2StringPretty(u1);//// ???????log.info("user1Json:{}",user1Json);//// ???????log.info("user1JsonPretty:{}",user1JsonPretty);////// ???????User user = JsonUtil.string2Obj(user1Json,User.class);////// ???????List<User> userList = Lists.newArrayList();// ???????userList.add(u1);// ???????userList.add(u2);//// ???????String userListStr = JsonUtil.obj2StringPretty(userList);//// ???????log.info("==================");//// ???????log.info(userListStr);////// ???????List<User> userListObj1 = JsonUtil.string2Obj(userListStr, new TypeReference<List<User>>() {// ???????});////// ???????List<User> userListObj2 = JsonUtil.string2Obj(userListStr,List.class,User.class); ???????System.out.println("end"); ???}}