运行第二个创建对象的活动并将其存储到ArrayList内的Singleton内
从广告Activity返回第一个Activity时，我收到此错误。
logcat的：
10-09 15:00:48.125: E/AndroidRuntime(4266): FATAL EXCEPTION: main
10-09 15:00:48.125: E/AndroidRuntime(4266): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.nanospark.cnc/com.nanospark.cnc.ContactCreateActivity}: java.lang.RuntimeException: Failed to invoke public org.joda.time.Chronology() with no args
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.ActivityThread.access$600(ActivityThread.java:141)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.os.Handler.dispatchMessage(Handler.java:99)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.os.Looper.loop(Looper.java:137)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.ActivityThread.main(ActivityThread.java:5103)
10-09 15:00:48.125: E/AndroidRuntime(4266): at java.lang.reflect.Method.invokeNative(Native Method)
10-09 15:00:48.125: E/AndroidRuntime(4266): at java.lang.reflect.Method.invoke(Method.java:525)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-09 15:00:48.125: E/AndroidRuntime(4266): at dalvik.system.NativeStart.main(Native Method)
10-09 15:00:48.125: E/AndroidRuntime(4266): Caused by: java.lang.RuntimeException: Failed to invoke public org.joda.time.Chronology() with no args
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.ConstructorConstructor$3.construct(ConstructorConstructor.java:107)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:173)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:95)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:183)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$1.read(ReflectiveTypeAdapterFactory.java:95)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.ReflectiveTypeAdapterFactory$Adapter.read(ReflectiveTypeAdapterFactory.java:183)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.TypeAdapterRuntimeTypeWrapper.read(TypeAdapterRuntimeTypeWrapper.java:40)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:81)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.bind.CollectionTypeAdapterFactory$Adapter.read(CollectionTypeAdapterFactory.java:60)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.Gson.fromJson(Gson.java:805)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.Gson.fromJson(Gson.java:770)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.Gson.fromJson(Gson.java:719)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.nanospark.cnc.GlobalData.retrieveGlobalDataFromStorage(GlobalData.java:92)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.nanospark.cnc.ContactCreateActivity.onCreate(ContactCreateActivity.java:38)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.Activity.performCreate(Activity.java:5133)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
10-09 15:00:48.125: E/AndroidRuntime(4266): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
10-09 15:00:48.125: E/AndroidRuntime(4266): ... 11 more
10-09 15:00:48.125: E/AndroidRuntime(4266): Caused by: java.lang.InstantiationException: can't instantiate class org.joda.time.Chronology
10-09 15:00:48.125: E/AndroidRuntime(4266): at java.lang.reflect.Constructor.constructNative(Native Method)
10-09 15:00:48.125: E/AndroidRuntime(4266): at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
10-09 15:00:48.125: E/AndroidRuntime(4266): at com.google.gson.internal.ConstructorConstructor$3.construct(ConstructorConstructor.java:104)
10-09 15:00:48.125: E/AndroidRuntime(4266): ... 27 more
执行JSON编写的Singleton代码：
public void storeGlobalData(Context context){
mPrefs = context.getSharedPreferences("com.nanospark.cnc", Context.MODE_PRIVATE);
preferenceEditor = mPrefs.edit();
Gson gson = new Gson();
//Transform the ArrayLists into JSON Data.
String machineProfileListJSON = gson.toJson(getMachineProfileList());
String contactInfoListJSON = gson.toJson(getContactInfoList());
String eventInfoListJSON = gson.toJson(getEventInfoList());
preferenceEditor.putString("machineProfileListJSONData", machineProfileListJSON);
preferenceEditor.putString("contactInfoListJSONData", contactInfoListJSON);
preferenceEditor.putString("eventInfoListJSONData", eventInfoListJSON);
//Commit the changes.
preferenceEditor.commit();
}
public void retrieveGlobalDataFromStorage(Context context){
mPrefs = context.getSharedPreferences("com.nanospark.cnc", Context.MODE_PRIVATE);
if(mPrefs.contains("machineProfileListJSONData")){
Gson gson = new Gson();
String machineProfileListJSON = mPrefs.getString("machineProfileListJSONData", "");
String contactInfoListJSON = mPrefs.getString("contactInfoListJSONData", "");
String eventInfoListJSON = mPrefs.getString("eventInfoListJSONData", "");
Type machineProfileListType = new TypeToken<ArrayList<MachineProfile>>() {}.getType();
machineProfileList = (gson.fromJson(machineProfileListJSON, machineProfileListType));
Type contactInfoListType = new TypeToken<ArrayList<ContactInfo>>() {}.getType();
contactInfoList = gson.fromJson(contactInfoListJSON, contactInfoListType );
Type eventListType = new TypeToken<ArrayList<Event>>() {}.getType();
eventInfoList = gson.fromJson(eventInfoListJSON, eventListType);
}
}
报告尝试撰写的事件类：
package com.nanospark.cnc;
import java.util.ArrayList;
import org.joda.time.LocalDate;
import org.joda.time.LocalTime;
public class ReportEvent extends Event {
public ReportEvent(String eventTitle,String eventDescription,int assignedPin, String trackingType,
LocalDate startDate, LocalDate endDate, boolean watchAllDay,
LocalTime startTime, LocalTime endTime, ArrayList<String> selectedDays,
ArrayList<ContactInfo> selectedContact, String formatChoice,
ReportTimeSpec reportTimingConfig) {
super(eventTitle,eventDescription, assignedPin, trackingType, startDate, endDate, watchAllDay,
startTime, endTime, selectedDays, selectedContact, formatChoice,
reportTimingConfig);
// TODO Auto-generated constructor stub
}
}
报告事件扩展的通用事件类：
package com.nanospark.cnc;
import java.util.ArrayList;
import java.util.Calendar;
import org.joda.time.LocalDate;
import org.joda.time.LocalTime;
public class Event {
String eventTitle;
String eventDescription;
int assignedPin;
String trackingType;
LocalDate startDate;
LocalDate endDate;
boolean watchAllDay;
LocalTime startTime;
LocalTime endTime;
ArrayList<String> selectedDays = new ArrayList<String>();
ArrayList<ContactInfo> selectedContact = new ArrayList<ContactInfo>();
String formatChoice;
ReportTimeSpec reportTimingConfigs;
public Event(){
}
public Event(String eventTitle, String eventDescription, int assignedPin, String trackingType,
LocalDate startDate, LocalDate endDate, boolean watchAllDay,
LocalTime startTime, LocalTime endTime, ArrayList<String> selectedDays,
ArrayList<ContactInfo> selectedContact, String formatChoice, ReportTimeSpec reportTimingConfigs) {
this.eventTitle = eventTitle;
this.eventDescription = eventDescription;
this.assignedPin = assignedPin;
this.trackingType = trackingType;
this.startDate = startDate;
this.endDate = endDate;
this.watchAllDay = watchAllDay;
this.startTime = startTime;
this.endTime = endTime;
this.selectedDays = selectedDays;
this.selectedContact = selectedContact;
this.formatChoice = formatChoice;
this.reportTimingConfigs = reportTimingConfigs;
}
public String getEventTitle() {
return eventTitle;
}
public void setEventTitle(String eventTitle) {
this.eventTitle = eventTitle;
}
public String getEventDescription() {
return eventDescription;
}
public void setEventDescription(String eventDescription) {
this.eventDescription = eventDescription;
}
public ReportTimeSpec getReportTimingConfigs() {
return reportTimingConfigs;
}
public void setReportTimingConfigs(ReportTimeSpec reportTimingConfigs) {
this.reportTimingConfigs = reportTimingConfigs;
}
public int getAssignedPin() {
return assignedPin;
}
public void setAssignedPin(int assignedPin) {
this.assignedPin = assignedPin;
}
public String getTrackingType() {
return trackingType;
}
public void setTrackingType(String trackingType) {
this.trackingType = trackingType;
}
public LocalDate getStartDate() {
return startDate;
}
public void setStartDate(LocalDate startDate) {
this.startDate = startDate;
}
public LocalDate getEndDate() {
return endDate;
}
public void setEndDate(LocalDate endDate) {
this.endDate = endDate;
}
public boolean isWatchAllDay() {
return watchAllDay;
}
public void setWatchAllDay(boolean watchAllDay) {
this.watchAllDay = watchAllDay;
}
public LocalTime getStartTime() {
return startTime;
}
public void setStartTime(LocalTime startTime) {
this.startTime = startTime;
}
public LocalTime getEndTime() {
return endTime;
}
public void setEndTime(LocalTime endTime) {
this.endTime = endTime;
}
public ArrayList<String> getSelectedDays() {
return selectedDays;
}
public void setSelectedDays(ArrayList<String> selectedDays) {
this.selectedDays = selectedDays;
}
public ArrayList<ContactInfo> getSelectedContact() {
return selectedContact;
}
public void setSelectedContact(ArrayList<ContactInfo> selectedContact) {
this.selectedContact = selectedContact;
}
public String getFormatChoice() {
return formatChoice;
}
public void setFormatChoice(String formatChoice) {
this.formatChoice = formatChoice;
}
public ReportTimeSpec getReportTimeSpec() {
return reportTimingConfigs;
}
public void setReportTimeSpec(ReportTimeSpec reportTimingConfigs) {
this.reportTimingConfigs = reportTimingConfigs;
}
@Override
public String toString(){
return this.eventTitle;
}
}
答案 0 :(得分：16)
来自https://github.com/gkopff/gson-javatime-serialisers的转换器用于来自Java8的 java.time 类，例如java.time.LocalDate。
但是你需要来自第三方库的 org.joda.time 类的转换器。您可以为它创建自定义转换器，例如：
转换为 org.joda.time.LocalDate
public class LocalDateSerializer implements JsonDeserializer<LocalDate>, JsonSerializer<LocalDate>
{
private static final DateTimeFormatter DATE_FORMAT = ISODateTimeFormat.date();
@Override
public LocalDate deserialize(final JsonElement je, final Type type,
final JsonDeserializationContext jdc) throws JsonParseException
{
final String dateAsString = je.getAsString();
if (dateAsString.length() == 0)
{
return null;
}
else
{
return DATE_FORMAT.parseLocalDate(dateAsString);
}
}
@Override
public JsonElement serialize(final LocalDate src, final Type typeOfSrc,
final JsonSerializationContext context)
{
String retVal;
if (src == null)
{
retVal = "";
}
else
{
retVal = DATE_FORMAT.print(src);
}
return new JsonPrimitive(retVal);
}
}
转换为 org.joda.time.LocalTime
public class LocalTimeSerializer implements JsonDeserializer<LocalTime>, JsonSerializer<LocalTime>
{
private static final DateTimeFormatter TIME_FORMAT = ISODateTimeFormat.timeNoMillis();
@Override
public LocalTime deserialize(final JsonElement je, final Type type,
final JsonDeserializationContext jdc) throws JsonParseException
{
final String dateAsString = je.getAsString();
if (dateAsString.length() == 0)
{
return null;
}
else
{
return TIME_FORMAT.parseLocalTime(dateAsString);
}
}
@Override
public JsonElement serialize(final LocalTime src, final Type typeOfSrc,
final JsonSerializationContext context)
{
String retVal;
if (src == null)
{
retVal = "";
}
else
{
retVal = TIME_FORMAT.print(src);
}
return new JsonPrimitive(retVal);
}
}
用法
public void retrieveGlobalDataFromStorage(Context context)
{
// ...
final GsonBuilder builder = new GsonBuilder()
.registerTypeAdapter(LocalDate.class, new LocalDateSerializer())
.registerTypeAdapter(LocalTime.class, new LocalTimeSerializer());
final Gson gson = builder.create();
// ...