我需要你的帮助才能理解为什么在我的方法中对象分配会返回Stack Overflow错误。
以下是方法：
public String toJson(){
JSONObject json;
json = new JSONObject(this); //error happens here...
return json.toString();
}
此类中的所有代码：
package com.neocloud.model;
import java.io.Serializable;
import com.amazonaws.util.json.JSONObject;
import com.neocloud.amazon.AwsSns;
import com.neocloud.model.dao.DeviceDAO;
import com.neocloud.model.dao.GroupDAO;
import com.neocloud.model.dao.SubscriptionDAO;
public class Subscription implements Serializable{
private static final long serialVersionUID = -3901714994276495605L;
private long id;
private Device dispositivo;
private Group grupo;
private String subscription;
public Subscription(){
clear();
}
public void clear(){
id = 0;
subscription = "";
grupo = new Group();
dispositivo = new Device();
}
public String toJson(){
JSONObject json;
json = new JSONObject(this); //error happens here...
return json.toString();
}
public String registerDB(boolean registrarSNS){
GroupDAO gDAO = new GroupDAO();
DeviceDAO dDAO = new DeviceDAO();
gDAO.selectById(this.grupo);
dDAO.selectById(this.dispositivo);
if (registrarSNS)
registerSNS(this.dispositivo.getEndPointArn(), this.grupo.getTopicArn());
SubscriptionDAO sDAO = new SubscriptionDAO();
return sDAO.insert(this);
}
public String registerSNS(String endpointArn, String topicArn){
String resposta;
AwsSns sns = AwsSns.getInstance();
resposta = ""+sns.addSubscriptionToTopic(endpointArn, topicArn);
setSubscription(resposta);
return resposta;
}
public String delete(){
AwsSns sns = AwsSns.getInstance();
SubscriptionDAO sDAO = new SubscriptionDAO();
sDAO.selectById(this);
sns.deleteSubscriptionFromTopic(this.subscription);
return sDAO.delete(this);
}
public long getId() {
return id;
}
public void setId(long id) {
if (this.id != id)
this.id = id;
}
public String getSubscription() {
return subscription;
}
public void setSubscription(String subscription) {
if (subscription != null){
if (!this.subscription.equals(subscription))
this.subscription = subscription;
}else
this.subscription = new String();
}
public Device getDispositivo() {
return dispositivo;
}
public void setDispositivo(Device dispositivo) {
if (dispositivo != null){
if (dispositivo.getId() != this.dispositivo.getId())
this.dispositivo = dispositivo;
}else
this.dispositivo = new Device();
}
public Group getGrupo() {
return grupo;
}
public void setGrupo(Group grupo) {
if (grupo != null){
if (grupo.getId() != this.grupo.getId())
this.grupo = grupo;
}else
this.grupo = new Group();
}
}
这是Device类：
package com.neocloud.model;
import java.io.Serializable;
import java.util.ArrayList;
import com.amazonaws.util.json.JSONException;
import com.amazonaws.util.json.JSONObject;
import com.neocloud.amazon.AwsSns;
import com.neocloud.model.dao.DeviceDAO;
import com.neocloud.model.enums.EEnvironment;
import com.neocloud.model.enums.EProduct;
import com.neocloud.model.enums.ESystem;
public class Device implements Serializable{
private static final long serialVersionUID = 8515474788917476721L;
private long id;
private String development;
private String SSL = "tls://gateway.push.apple.com:2195";
private String feedback = "tls://feedback.push.apple.com:2196";
private String sandboxSSL = "tls://gateway.sandbox.push.apple.com:2195";
private String sandboxFeedback = "tls://feedback.sandbox.push.apple.com:2196";
private String message;
private String endPointArn;
private String deviceToken;
private EProduct appID;
private String appVersion;
private String deviceUID;
private String deviceName;
private String deviceModel;
private String deviceVersion;
private boolean pushBadge;
private boolean pushAlert;
private boolean pushSound;
private ESystem system;
private EEnvironment environment;
private ArrayList<Subscription> subscriptions;
private String deviceUser;
public Device(){
clear();
}
public String deleteToken(){
/*
*
* terminar aqui ainda...
*
DeviceDAO dDAO = new DeviceDAO();
AwsSns sns = AwsSns.getInstance();
sns.deleteDeviceEndpoint(getEndPointArn());
ArrayList<String> subscriptions = dDAO.getSubscriptionsFromEndpointArn(this);
for (int i=0; i<subscriptions.size();i++){
sns.deleteSubscriptionFromTopic(subscriptions.get(i));
}
return dDAO.delete(this);
*/ return "";
}
public String updateToken(){
if ((system == ESystem.IOS) && (deviceToken.length() != 64))
return "deviceTokenlen64";
AwsSns sns = AwsSns.getInstance();
String jsonResposta = ""+sns.updateDeviceEndpoint(getEndPointArn(), deviceToken);
DeviceDAO dDAO = new DeviceDAO();
dDAO.update(this);
return jsonResposta;
}
public String registerDevice(){
if (appVersion.length() == 0)
return "applen0";
if (deviceUID.length() > 40)
return "deviceUID40";
if ((system == ESystem.IOS) && (deviceToken.length() != 64))
return "deviceTokenlen64";
if (deviceName.length() == 0)
return "deviceNamelen0";
if (deviceModel.length() == 0)
return "deviceModellen0";
if (deviceVersion.length() == 0)
return "deviceVersionlen0";
AwsSns sns = AwsSns.getInstance();
String jsonResposta = null;
switch (getAppID()) {
case MODULE: {
if (system == ESystem.IOS)
jsonResposta = ""+sns.createDeviceEndpoint(deviceToken, Constants.ENDPOINTMODULEIOS);
else if (system == ESystem.ANDROID)
jsonResposta = ""+sns.createDeviceEndpoint(deviceToken, Constants.ENDPOINTMODULEANDROID);
break;
}
case HOSTPRO: {
if (system == ESystem.IOS)
jsonResposta = ""+sns.createDeviceEndpoint(deviceToken, Constants.ENDPOINTHOSTPROIOS);
else if (system == ESystem.ANDROID)
jsonResposta = ""+sns.createDeviceEndpoint(deviceToken, Constants.ENDPOINTHOSTPROANDROID);
break;
}
case CONNEXOON: {
if (system == ESystem.IOS)
jsonResposta = ""+sns.createDeviceEndpoint(deviceToken, Constants.ENDPOINTCONNEXOONIOS);
else if (system == ESystem.ANDROID)
jsonResposta = ""+sns.createDeviceEndpoint(deviceToken, Constants.ENDPOINTCONNEXOONANDROID);
break;
}
case TAHOMA: {
break;
}
case MINIBOX: {
break;
}
case NONE: {
}
default: {
}
}
if (jsonResposta != null){
JSONObject json;
try {
jsonResposta = jsonResposta.replace("}", "\"}").replace("arn", "\"arn");
jsonResposta = jsonResposta.replace("{EndPointArn:", "{\"EndPointArn\":");
json = new JSONObject(jsonResposta);
setEndPointArn(json.getString("EndpointArn"));
} catch (JSONException e) {
e.printStackTrace();
}
}
Subscription subscription;
switch (getAppID()){
case MODULE: {
subscription = new Subscription();
subscription.getGrupo().setId(19);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICMODULEGERAL);
subscriptions.add(subscription);
if (system == ESystem.IOS){
subscription = new Subscription();
subscription.getGrupo().setId(25);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICMODULEIOS);
subscriptions.add(subscription);
}
else if (system == ESystem.ANDROID){
subscription = new Subscription();
subscription.getGrupo().setId(22);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICMODULEANDROID);
subscriptions.add(subscription);
}
break;
}
case HOSTPRO: {
subscription = new Subscription();
subscription.getGrupo().setId(10);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICHOSTPROGERAL);
subscriptions.add(subscription);
if (system == ESystem.IOS){
subscription = new Subscription();
subscription.getGrupo().setId(16);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICHOSTPROIOS);
subscriptions.add(subscription);
}
else if (system == ESystem.ANDROID){
subscription = new Subscription();
subscription.getGrupo().setId(13);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICHOSTPROANDROID);
subscriptions.add(subscription);
}
break;
}
case CONNEXOON: {
subscription = new Subscription();
subscription.getGrupo().setId(1);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICCONNEXOONGERAL);
subscriptions.add(subscription);
if (system == ESystem.IOS){
subscription = new Subscription();
subscription.getGrupo().setId(7);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICCONNEXOONIOS);
subscriptions.add(subscription);
}
else if (system == ESystem.ANDROID){
subscription = new Subscription();
subscription.getGrupo().setId(4);
subscription.registerSNS(getEndPointArn(), Constants.ENDPOINTTOPICCONNEXOONANDROID);
subscriptions.add(subscription);
}
break;
}
case TAHOMA: {
break;
}
case MINIBOX: {
break;
}
case NONE: {
}
default: {
}
}
DeviceDAO dDAO = new DeviceDAO();
return dDAO.insert(this);
}
public void clear(){
development = "";
message = "";
endPointArn = "";
deviceToken = "";
appID = EProduct.NONE;
appVersion = "";
deviceUID = "";
deviceName = "";
deviceModel = "";
deviceVersion = "";
pushBadge = false;
pushAlert = false;
pushSound = false;
system = ESystem.NONE;
environment = EEnvironment.HOMOLOGATION;
subscriptions = new ArrayList<Subscription>();
deviceUser = "";
}
public String toJson(){
JSONObject json;
json = new JSONObject(this);
return json.toString();
}
public String getDevelopment() {
return development;
}
public void setDevelopment(String development) {
if (development != null){
if (!development.equals(this.development))
this.development = development;
}
this.development = new String();
}
public String getSSL() {
return SSL;
}
public void setSSL(String sSL) {
if (sSL != null){
if (!sSL.equals(this.SSL))
this.SSL = sSL;
}
else
this.SSL = new String();
}
public String getFeedback() {
return feedback;
}
public void setFeedback(String feedback) {
if (feedback != null){
if (!feedback.equals(this.feedback))
this.feedback = feedback;
}
this.feedback = new String();
}
public String getSandboxSSL() {
return sandboxSSL;
}
public void setSandboxSSL(String sandboxSSL) {
if (sandboxSSL != null){
if (!sandboxSSL.equals(this.sandboxSSL))
this.sandboxSSL = sandboxSSL;
}else
this.sandboxSSL = new String();
}
public String getSandboxFeedback() {
return sandboxFeedback;
}
public void setSandboxFeedback(String sandboxFeedback) {
if (sandboxFeedback != null){
if (!sandboxFeedback.equals(this.sandboxFeedback))
this.sandboxFeedback = sandboxFeedback;
}else
this.sandboxFeedback = new String();
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
if (message != null){
if (!message.equals(this.message))
this.message = message;
}else
this.message = new String();
}
public String getEndPointArn() {
return endPointArn;
}
public void setEndPointArn(String createPlatformEndpointResult) {
if (createPlatformEndpointResult != null){
if (!createPlatformEndpointResult.equals(this.endPointArn))
this.endPointArn = createPlatformEndpointResult;
}else
this.endPointArn = new String();
}
public String getDeviceToken() {
return deviceToken;
}
public void setDeviceToken(String deviceToken) {
if (deviceToken != null){
if (!deviceToken.equals(this.deviceToken))
this.deviceToken = deviceToken;
}else
this.deviceToken = new String();
}
public EProduct getAppID() {
return appID ;
}
public void setAppID(EProduct appID){
if (appID != this.appID)
this.appID = appID;
}
public String getAppVersion() {
return appVersion;
}
public void setAppVersion(String appVersion) {
if (appVersion != null){
if (!appVersion.equals(this.appVersion))
this.appVersion = appVersion;
}else
this.appVersion = new String();
}
public String getDeviceUID() {
return deviceUID;
}
public void setDeviceUID(String deviceUID) {
if (deviceUID != null){
if (!deviceUID.equals(this.deviceUID))
this.deviceUID = deviceUID;
}else
this.deviceUID = new String();
}
public String getDeviceName() {
return deviceName;
}
public void setDeviceName(String deviceName) {
if (deviceName != null){
if (!deviceName.equals(this.deviceName))
this.deviceName = deviceName;
}else
this.deviceName = new String();
}
public String getDeviceModel() {
return deviceModel;
}
public void setDeviceModel(String deviceModel) {
if (deviceModel != null){
if (!deviceModel.equals(this.deviceModel))
this.deviceModel = deviceModel;
}else
this.deviceModel = new String();
}
public String getDeviceVersion() {
return deviceVersion;
}
public void setDeviceVersion(String deviceVersion) {
if (deviceVersion != null){
if (!deviceVersion.equals(this.deviceVersion))
this.deviceVersion = deviceVersion;
}else
this.deviceVersion = new String();
}
public boolean isPushBadge() {
return pushBadge;
}
public void setPushBadge(boolean pushBadge) {
if (pushBadge != this.pushBadge)
this.pushBadge = pushBadge;
}
public boolean isPushAlert() {
return pushAlert;
}
public void setPushAlert(boolean pushAlert) {
if (pushAlert != this.pushAlert)
this.pushAlert = pushAlert;
}
public boolean isPushSound() {
return pushSound;
}
public void setPushSound(boolean pushSound) {
if (this.pushSound != pushSound)
this.pushSound = pushSound;
}
public ESystem getSystem() {
return system;
}
public void setTipoSmartphone(ESystem system) {
if (system != this.system)
this.system = system;
}
public EEnvironment getEnvironment() {
return environment;
}
public void setEnvironment(EEnvironment environment) {
if (environment != this.environment)
this.environment = environment;
}
public long getId() {
return id;
}
public void setId(long id) {
if (this.id != id)
this.id = id;
}
public void setSystem(ESystem system) {
if (system != this.system)
this.system = system;
}
public ArrayList<Subscription> getSubscriptions() {
return subscriptions;
}
public void setSubscriptions(ArrayList<Subscription> subscriptions) {
if (subscriptions != null)
this.subscriptions = subscriptions;
else
this.subscriptions = new ArrayList<Subscription>();
}
public String getDeviceUser() {
return deviceUser;
}
public void setDeviceUser(String deviceUser) {
if (deviceUser != null){
if (!deviceUser.equals(this.deviceUser))
this.deviceUser = deviceUser;
}else
this.deviceUser = new String();
}
}
这是Group类：
package com.neocloud.model;
import java.io.Serializable;
import java.util.ArrayList;
import com.amazonaws.util.json.JSONException;
import com.amazonaws.util.json.JSONObject;
import com.neocloud.amazon.AwsSns;
import com.neocloud.model.dao.GroupDAO;
public class Group implements Serializable{
private static final long serialVersionUID = -5032857327241801763L;
private long id;
private String nome;
private String topicArn;
public Group(){
this.clear();
}
public void clear(){
this.id = 0;
this.nome = new String();
this.topicArn = new String();
}
public String registerGrupo(){
AwsSns snsClient = AwsSns.getInstance();
String topic = ""+snsClient.createTopic(this.nome);
JSONObject json;
String jsonResposta = topic;
try {
jsonResposta = jsonResposta.replace("}", "\"}").replace("arn", "\"arn");
jsonResposta = jsonResposta.replace("{TopicArn:", "{\"TopicArn\":");
json = new JSONObject(jsonResposta);
setTopicArn(json.getString("TopicArn"));
} catch (JSONException e) {
e.printStackTrace();
}
GroupDAO grupoDAO = new GroupDAO();
return grupoDAO.insert(this);
}
public String deleteGrupo(){
AwsSns snsClient = AwsSns.getInstance();
GroupDAO grupoDAO = new GroupDAO();
ArrayList<Group> grupos = grupoDAO.select(this);
if (grupos.size() > 0){
for (int i = 0; i<grupos.size(); i++){
this.topicArn = grupos.get(i).getTopicArn();
this.nome = grupos.get(i).getNome();
this.id = grupos.get(i).getId();
snsClient.deleteTopic(this.topicArn);
}
return grupoDAO.delete(this);
}
return "-1";
}
public String toJson(){
JSONObject json;
json = new JSONObject(this);
return json.toString();
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getNome() {
return nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public String getTopicArn() {
return topicArn;
}
public void setTopicArn(String topicArn) {
this.topicArn = topicArn;
}
}
这是Tomcat日志：
线程中的异常＆＃34; http-bio-8080-exec-5＆＃34; java.lang.StackOverflowError at java.lang.reflect.Executable。（未知来源）at java.lang.reflect.Method。（未知来源）at java.lang.reflect.Method.copy（未知来源）at java.lang.reflect.ReflectAccess.copyMethod（未知来源）at sun.reflect.ReflectionFactory.copyMethod（未知来源）at java.lang.Class.copyMethods（未知来源）at java.lang.Class.getMethods（未知来源）at com.amazonaws.util.json.JSONObject.populateMap（JSONObject.java:930） 在com.amazonaws.util.json.JSONObject。（JSONObject.java:285）at com.amazonaws.util.json.JSONObject.wrap（JSONObject.java:1540）at at com.amazonaws.util.json.JSONObject.populateMap（JSONObject.java:960）
感谢您的帮助！
答案 0 :(得分：1)
可能是对象中的循环引用。
答案 1 :(得分：1)
json = new JSONObject(this);
你正在尝试JSONify这个
id = 0;
subscription = "";
grupo = new Group();
dispositivo = new Device();
我认为，不知何故，JSONify Group和Device无法理解。你能告诉我们这些课程的代码吗？
更新：在Subscription.clear()方法中，您会影响new Group()＆amp;一个new Device()。创建new Device()时，方法Device.clear()会被调用并创建new ArrayList<Subscription>()，该方法会调用方法Subscription.clear()，这会影响new Group() 1}}＆amp;一个new Device()等等。您无限循环，这就是您收到StackOverflow错误的原因。很遗憾，您订阅的是一个由订阅的ArrayList组成的Group，它也是由Groups等组成的。
答案 2 :(得分：0)
也许你有一个循环参考......
Object a = X;
Object c = Y;
a.prop = Y;
c.prop2 = X;
然后，你的JSON（a）是
{
prop : {
prop2 : {
prop : Y (Y have prop2 again)
/*infinite..*/
}
}
}