无法使用jackson API将json字符串映射到java对象
我正在编写一个web服务(服务器+客户端)。我能够创建一个服务,它会返回以下json无法使用jackson API将json字符串映射到java对象,java,json,web-services,rest,jackson,Java,Json,Web Services,Rest,Jackson,我正在编写一个web服务(服务器+客户端)。我能够创建一个服务,它会返回以下json { "cities": { "city": [ { "name": "New Delhi", "population": "19M", "telephonecode": "011" }, { "name": "Mumbai", "popu
{
"cities": {
"city": [
{
"name": "New Delhi",
"population": "19M",
"telephonecode": "011"
},
{
"name": "Mumbai",
"population": "21M",
"telephonecode": "022"
},
{
"name": "Chennai",
"population": "10M",
"telephonecode": "044"
}
]
}
}
我的POJO是
@XmlRootElement(name = "cities")
public class RestFulCities {
List<RestFulCity> restFulCityList;
@XmlElement(name = "city")
public List<RestFulCity> getRestFulCityList() {
return restFulCityList;
}
public void setRestFulCityList(List<RestFulCity> restFulCityList) {
this.restFulCityList = restFulCityList;
}
}
@XmlRootElement(name = "city")
public class RestFulCity {
private String name;
private String telephonecode;
private String population;
public RestFulCity(String name, String telephonecode, String population) {
this.name = name;
this.telephonecode = telephonecode;
this.population = population;
}
public RestFulCity(City city) {
this.name = city.getName();
this.telephonecode = city.getTelephonecode();
this.population = city.getPopulation();
}
@XmlElement
public String getName() {
return name;
}
@XmlElement
public String getTelephonecode() {
return telephonecode;
}
@XmlElement
public String getPopulation() {
return population;
}
}
但问题是:我得到了以下例外
org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "cities"(Class com.techartifact.example.spring.model.RestFulCities), not marked as ignorable
at [Source: java.io.StringReader@1d35bf2; line: 1, column: 12] (through reference chain: com.techartifact.example.spring.model.RestFulCities["cities"])
当我使用以下属性时:
@JsonIgnoreProperties(ignoreUnknown = true)
虽然我没有得到异常,但是我的restFulCityList为null,这是不需要的
请提供帮助您正在使用JAXB注释,因此需要使用正确的模块正确配置
ObjectMapper
;你需要这个项目。使用您喜爱的依赖关系管理系统添加它,并按如下方式使用:
JaxbAnnotationModule module = new JaxbAnnotationModule();
// configure as necessary
objectMapper.registerModule(module);
注意:这是给Jackson 2.x的。默认情况下,Jackson1.x支持JAXB,但该版本不再受支持,并且考虑到您有这个问题,您可能正在使用Jackson2.x
更新:JAXB注释非常适合与XML系统进行互操作,但如果可以的话,您应该真正使用Jackson自己的注释。这样就不需要jaxb模块和ObjectMapper
的配置。此外,Jackson中的某些功能只能通过其注释提供,因为在JAXB中没有等效功能。找到了解决方案
使用以下代码:
JSONObject primary_contact = new JSONObject(s);
String s1 = primary_contact.getString("cities");
JSONObject primary_contact1 = new JSONObject(s1);
String s2 = primary_contact1.getString("city");
List<City> citiesList = new ObjectMapper().readValue(s2, new TypeReference<List<City>>() { });
public class Client {
static final String REST_URI = "http://localhost:8080/springrest/rest/";
static final String CITIES = "cities";
static final String CITIES_BHUVAN = "cities/bhuvan";
static final String BHUVAN = "bhuvan";
static final String BHUVAN_BHUVAN = "bhuvan/bhuvan";
public static void main(String[] args) throws JSONException {
String s = "";
WebClient plainAddClient = WebClient.create(REST_URI);
plainAddClient.path(CITIES).accept("application/json");
s = plainAddClient.get(String.class);
try {
JSONObject primary_contact = new JSONObject(s);
String s1 = primary_contact.getString("cities");
JSONObject primary_contact1 = new JSONObject(s1);
String s2 = primary_contact1.getString("city");
List<City> citiesList = new ObjectMapper().readValue(s2, new TypeReference<List<City>>() { });
for(City city : citiesList) {
System.out.println("----------START---------");
System.out.println(city.getName());
System.out.println(city.getPopulation());
System.out.println(city.getTelephonecode());
System.out.println("---------END----------");
}
} catch (JsonParseException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
WebClient xmlAddClient = WebClient.create(REST_URI);
xmlAddClient.path(CITIES_BHUVAN).accept("application/json");
s = xmlAddClient.get(String.class);
System.out.println(s);
WebClient plainSubClient = WebClient.create(REST_URI);
plainSubClient.path(BHUVAN).accept("application/json");
s = plainSubClient.get(String.class);
System.out.println(s);
WebClient xmlSubClient = WebClient.create(REST_URI);
xmlSubClient.path(BHUVAN_BHUVAN).accept("application/json");
s = xmlSubClient.get(String.class);
System.out.println(s);
}
}
JSONObject primary\u contact=新的JSONObject;
字符串s1=主要联系人.getString(“城市”);
JSONObject primary_contact1=新JSONObject(s1);
字符串s2=主触点1.getString(“城市”);
List citiesList=new ObjectMapper().readValue(s2,new TypeReference(){});
客户端代码应为:
JSONObject primary_contact = new JSONObject(s);
String s1 = primary_contact.getString("cities");
JSONObject primary_contact1 = new JSONObject(s1);
String s2 = primary_contact1.getString("city");
List<City> citiesList = new ObjectMapper().readValue(s2, new TypeReference<List<City>>() { });
public class Client {
static final String REST_URI = "http://localhost:8080/springrest/rest/";
static final String CITIES = "cities";
static final String CITIES_BHUVAN = "cities/bhuvan";
static final String BHUVAN = "bhuvan";
static final String BHUVAN_BHUVAN = "bhuvan/bhuvan";
public static void main(String[] args) throws JSONException {
String s = "";
WebClient plainAddClient = WebClient.create(REST_URI);
plainAddClient.path(CITIES).accept("application/json");
s = plainAddClient.get(String.class);
try {
JSONObject primary_contact = new JSONObject(s);
String s1 = primary_contact.getString("cities");
JSONObject primary_contact1 = new JSONObject(s1);
String s2 = primary_contact1.getString("city");
List<City> citiesList = new ObjectMapper().readValue(s2, new TypeReference<List<City>>() { });
for(City city : citiesList) {
System.out.println("----------START---------");
System.out.println(city.getName());
System.out.println(city.getPopulation());
System.out.println(city.getTelephonecode());
System.out.println("---------END----------");
}
} catch (JsonParseException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
WebClient xmlAddClient = WebClient.create(REST_URI);
xmlAddClient.path(CITIES_BHUVAN).accept("application/json");
s = xmlAddClient.get(String.class);
System.out.println(s);
WebClient plainSubClient = WebClient.create(REST_URI);
plainSubClient.path(BHUVAN).accept("application/json");
s = plainSubClient.get(String.class);
System.out.println(s);
WebClient xmlSubClient = WebClient.create(REST_URI);
xmlSubClient.path(BHUVAN_BHUVAN).accept("application/json");
s = xmlSubClient.get(String.class);
System.out.println(s);
}
}
公共类客户端{
静态最终字符串REST_URI=”http://localhost:8080/springrest/rest/";
静态最终字符串CITIES=“CITIES”;
静态最终字符串CITIES_BHUVAN=“CITIES/BHUVAN”;
静态最终字符串BHUVAN=“BHUVAN”;
静态最终字符串BHUVAN_BHUVAN=“BHUVAN/BHUVAN”;
公共静态void main(字符串[]args)抛出JSONException{
字符串s=“”;
WebClient plainAddClient=WebClient.create(REST\u URI);
plainAddClient.path(CITIES.accept(“application/json”);
s=plainAddClient.get(String.class);
试一试{
JSONObject primary_contact=新的JSONObject;
字符串s1=主要联系人.getString(“城市”);
JSONObject primary_contact1=新JSONObject(s1);
字符串s2=主触点1.getString(“城市”);
List citiesList=new ObjectMapper().readValue(s2,new TypeReference(){});
for(城市:citiesList){
System.out.println(“------------START----------”);
System.out.println(city.getName());
System.out.println(city.getPopulation());
System.out.println(city.getTelephonecode());
System.out.println(“------结束------------”;
}
}捕获(JSONParsee异常){
e、 printStackTrace();
}捕获(JsonMappingException e){
e、 printStackTrace();
}捕获(IOE异常){
e、 printStackTrace();
}
WebClient xmlAddClient=WebClient.create(REST\u URI);
xmlAddClient.path(CITIES_BHUVAN).accept(“application/json”);
s=xmlAddClient.get(String.class);
系统输出打印项次;
WebClient printsubclient=WebClient.create(REST\u URI);
plainSubClient.path(BHUVAN.accept)(“应用程序/json”);
s=plainSubClient.get(String.class);
系统输出打印项次;
WebClient xmlSubClient=WebClient.create(REST\u URI);
xmlSubClient.path(BHUVAN_BHUVAN).accept(“application/json”);
s=xmlSubClient.get(String.class);
系统输出打印项次;
}
}
为什么有两次@XmlRootElement(name=“city”)
?您还没有使用@XmlRootElement(name=“cities”)
定义任何内容,我认为这应该是列表