我使用Codehaus Jackson将json数据转换为带有对象数组的POJO。 我遇到了对象数组的问题。我收到的错误如“无法反序列化实例......超出START_ARRAY标记”。
以下是我的代码
{
"tripType": "OneWay",
"tripInfos":[
{
"from":"EARTH",
"to":"MOON",
"fromSchedule":"2015-12-21T04:30:00",
"toSchedule":"2015-12-21T06:50:00"
},
{
"from":"MOON",
"to":"MARS",
"fromSchedule":"2015-12-21T03:30:00",
"toSchedule":"2015-12-21T011:10:00"
},
{
"from":"VENUS",
"to":"KEPLER",
"fromSchedule":"2015-12-21T01:30:00",
"toSchedule":"2015-12-21T22:30:00"
},
{
"from":"EARTH",
"to":"SUN",
"fromSchedule":"2015-12-20T02:30:00",
"toSchedule":"2015-12-29T15:10:00"
}
],
"adultFare":{
"paxType":"ADT",
"baseFare":"1000",
"totalFeesAndTaxes":"300",
"totalAmount":"1300.00"
},
"childFare":{
"paxType":"CHD",
"baseFare":"750",
"totalFeesAndTaxes":"250",
"totalAmount":"1000.00"
},
"infantFare":{
"paxType":"INF",
"baseFare":"250",
"totalFeesAndTaxes":"25",
"totalAmount":"275.00"
},
"adultCount":"1",
"childCount":"1",
"infantCount":"2"
}
package com.jgtt.samples;
import java.util.*;
import org.codehaus.jackson.annotate.JsonProperty;
public class JacksonFlightItineraryPrice {
private String tripType;
@JsonProperty("tripInfos")
private JacksonFlightItineraryPrice.TripInfo tripInfos;
private JacksonFlightItineraryPrice.PaxFare adultFare;
private JacksonFlightItineraryPrice.PaxFare childFare;
private JacksonFlightItineraryPrice.PaxFare infantFare;
private short adultCount;
private short childCount;
private short infantCount;
public JacksonFlightItineraryPrice() {}
public String getTripType() {
return (this.tripType);
}
public void setTripType(String tripType) {
this.tripType = tripType;
}
public JacksonFlightItineraryPrice.TripInfo getTripInfos() {
return (this.tripInfos);
}
public void setTripInfos(JacksonFlightItineraryPrice.TripInfo tripInfos) {
this.tripInfos = tripInfos;
}
public JacksonFlightItineraryPrice.PaxFare getAdultFare() {
return (this.adultFare);
}
public void setAdultFare(JacksonFlightItineraryPrice.PaxFare adultFare) {
this.adultFare = adultFare;
}
public JacksonFlightItineraryPrice.PaxFare getChildFare() {
return (this.childFare);
}
public void setChildFare(JacksonFlightItineraryPrice.PaxFare childFare) {
this.childFare = childFare;
}
public JacksonFlightItineraryPrice.PaxFare getInfantFare() {
return (this.infantFare);
}
public void setInfantFare(JacksonFlightItineraryPrice.PaxFare infantFare) {
this.infantFare = infantFare;
}
public short getAdultCount() {
return (this.adultCount);
}
public void setAdultCount(short adultCount) {
this.adultCount = adultCount;
}
public short getChildCount() {
return (this.childCount);
}
public void setChildCount(short childCount) {
this.childCount = childCount;
}
public short getInfantCount() {
return (this.infantCount);
}
public void setInfantCount(short infantCount) {
this.infantCount = infantCount;
}
public static class TripInfo {
private List<JacksonFlightItineraryPrice.FlightInfoParameter> flightInfoParameters;
public List getFlightInfoParameters() {
return (this.flightInfoParameters);
}
public void setFlightInfoParameters(List flightInfoParameters) {
this.flightInfoParameters = flightInfoParameters;
}
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("[\n");
if(null != flightInfoParameters){
sb.append(" flightInfoParameters:\n");
boolean isFirst = true;
for(FlightInfoParameter f : flightInfoParameters){
if(!isFirst){
sb.append(",\n");
}
sb.append(f);
isFirst = false;
}
sb.append("\n");
}
else {
sb.append(" flightInfoParameters=null\n");
}
sb.append("]");
return sb.toString();
}
}
public static class FlightInfoParameter {
private String from;
private String to;
private String fromSchedule;
private String toSchedule;
public String getFrom() {
return from;
}
public void setFrom(String from) {
this.from = from;
}
public String getTo() {
return to;
}
public void setTo(String to) {
this.to = to;
}
public String getFromSchedule() {
return fromSchedule;
}
public void setFromSchedule(String fromSchedule) {
this.fromSchedule = fromSchedule;
}
public String getToSchedule() {
return toSchedule;
}
public void setToSchedule(String toSchedule) {
this.toSchedule = toSchedule;
}
@Override
public String toString() {
return "User [ "+from+"(" + fromSchedule + ") -> " + to + "(" + toSchedule + ") ]";
}
}
public static class PaxFare {
private String paxType;
private Double baseFare;
private Double totalFeesAndTaxes;
private Double totalAmount;
public String getPaxType() {
return paxType;
}
public void setPaxType(String paxType) {
this.paxType = paxType;
}
public Double getBaseFare() {
return baseFare;
}
public void setBaseFare(Double baseFare) {
this.baseFare = baseFare;
}
public Double getTotalFeesAndTaxes() {
return totalFeesAndTaxes;
}
public void setTotalFeesAndTaxes(Double totalFeesAndTaxes) {
this.totalFeesAndTaxes = totalFeesAndTaxes;
}
public Double getTotalAmount() {
return totalAmount;
}
public void setTotalAmount(Double totalAmount) {
this.totalAmount = totalAmount;
}
@Override
public String toString() {
return "User [paxType=" + paxType + ", baseFare=" + baseFare + ", totalFeesAndTaxes" + totalFeesAndTaxes + ", totalAmount=" + totalAmount + "]";
}
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append("[\n");
sb.append(" tripType=" + tripType + ",\n");
sb.append(" tripInfos=" + tripInfos + ",\n");
sb.append(" adultFare=" + adultFare + ",\n");
sb.append(" childFare=" + childFare + ",\n");
sb.append(" infantFare=" + infantFare + ",\n");
sb.append(" adultCount=" + adultCount + ",\n");
sb.append(" childCount=" + childCount + ",\n");
sb.append(" infantCount=" + infantCount + "\n]");
return sb.toString();
}
}
package com.jgtt.samples;
import java.util.*;
import java.io.File;
import java.io.IOException;
import org.codehaus.jackson.JsonGenerationException;
import org.codehaus.jackson.map.ObjectMapper;
import org.codehaus.jackson.map.JsonMappingException;
import org.codehaus.jackson.type.TypeReference;
import org.codehaus.jackson.map.type.CollectionType;
import org.codehaus.jackson.map.type.TypeFactory;
public class JacksonExample {
private static void flightJsonToPojo(){
ObjectMapper mapper = new ObjectMapper();
try {
String file_url = "d:\\Work files\\Java Test Codes\\Jackson\\flightItineraryPrice.json";
File jsonFile = new File(file_url);
JacksonFlightItineraryPrice flightInfo = mapper.readValue(jsonFile, JacksonFlightItineraryPrice.class);
System.out.println(flightInfo);
} catch (JsonGenerationException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
flightJsonToPojo();
}
}
我遇到问题的json数据中唯一的部分是“tripInfos”，因为它的值是对象的arraylist。如果我删除tripInfos ......一切正常......但我真的也需要它。
希望有人能给我指路：）
答案 0 :(得分：1)
班级JacksonFlightItineraryPrice有一个属性tripInfos，不是数组：
@JsonProperty("tripInfos")
private JacksonFlightItineraryPrice.TripInfo tripInfos;
且TripInfo flightInfoParameters List为List<JacksonFlightItineraryPrice.FlightInfoParameter>
但是你的json tripInfos是一个JacksonFlightItineraryPrice.FlightInfoParameter的数组。
相反它应该是：
{
"tripType": "OneWay",
"tripInfos": {
"flightInfoParameters" : [
{
"from":"EARTH",
"to":"MOON",
"fromSchedule":"2015-12-21T04:30:00",
"toSchedule":"2015-12-21T06:50:00"
},
{
"from":"MOON",
"to":"MARS",
"fromSchedule":"2015-12-21T03:30:00",
"toSchedule":"2015-12-21T011:10:00"
},
{
"from":"VENUS",
"to":"KEPLER",
"fromSchedule":"2015-12-21T01:30:00",
"toSchedule":"2015-12-21T22:30:00"
},
{
"from":"EARTH",
"to":"SUN",
"fromSchedule":"2015-12-20T02:30:00",
"toSchedule":"2015-12-29T15:10:00"
}
]
},
"adultFare":{
"paxType":"ADT",
"baseFare":"1000",
"totalFeesAndTaxes":"300",
"totalAmount":"1300.00"
},
"childFare":{
"paxType":"CHD",
"baseFare":"750",
"totalFeesAndTaxes":"250",
"totalAmount":"1000.00"
},
"infantFare":{
"paxType":"INF",
"baseFare":"250",
"totalFeesAndTaxes":"25",
"totalAmount":"275.00"
},
"adultCount":"1",
"childCount":"1",
"infantCount":"2"
}
或者如果您无法更改JSON，那么在JacksonFlightItineraryPrice中，属性tripInfos应该是FlightInfoParameter的列表：
@JsonProperty("tripInfos")
private List<JacksonFlightItineraryPrice.FlightInfoParameter> tripInfos;