如何从特定日期的哈希表中删除数据
我想从特定日期的哈希表中删除数据，哈希表的类型（字符串，矢量）。最初我检查如果散列表包含usrDate如果是的话我需要删除所有的数据frm散列表仅用于usrDate，并添加新的数据是listEvents.But其他日期的散列表中的包含不应该被删除。如何从特定日期的哈希表中删除数据
listEvents.addElement(eventBean);//new data is here
for (int i = 0; i < listEvents.size();i++) {
EventData e = (EventData)listEvents.elementAt(i);
}
//checking if hashtable has given date
if (listUserEvents.containsKey(usrDate)) {
Vector info = (Vector)listUserEvents.get(usrDate);
info.addElement(eventBean);
listUserEvents.put(usrDate,info);
} else {
listUserEvents.put(usrDate,listEvents);
}
我只是想的listEvents添加到哈希表在指定日期的，不影响Hashtable将有一些其他的日期数据的其他数据。
private Hashtable getEvents(String usrDate, String timezone) {
try {
listUserEvents = getUserInfo();
listEvents = new Vector();
Calendar calendarLocalEvent = Calendar.getInstance();
// fetches time zone
TimeZone timeZoneEvent = calendarLocalEvent.getTimeZone();
System.out.println("Time Zone first-->"
+ timeZoneEvent.getDefault());
if (timezone.equals(timeZoneEvent.getDefault())) {
;
} else {
TimeZone timeZoneChange = TimeZone.getTimeZone(timezone);
System.out.println("Time Zone change-->" +timeZoneChange);
Device.setTimeZone(timeZoneChange);
}
EventList eventList = (EventList) PIM.getInstance().openPIMList(
PIM.EVENT_LIST, PIM.READ_ONLY);
Enumeration events = eventList.items();
while (events.hasMoreElements()) {
System.out.println("in while");
Event event = (Event) events.nextElement();
if (eventList.isSupportedField(Event.START)
&& event.countValues(Event.START) > 0)
{
long start = event.getDate(Event.START, 0);
SimpleDateFormat sdf = new SimpleDateFormat(
"MMM dd,yyyy HH:mm");
SimpleDateFormat sdf_start = new SimpleDateFormat("HH:mm");
SimpleDateFormat sdf_start_min = new SimpleDateFormat("HH");
String dateString = sdf.formatLocal(start);
String timeString = sdf_start.formatLocal(start);
String hour = sdf_start_min.formatLocal(start);
SimpleDateFormat sdf1 = new SimpleDateFormat("MMM dd,yyyy");
String date = sdf1.formatLocal(start);
System.out.println("dates are :" + date +"user" + usrDate);
if (usrDate.equalsIgnoreCase(date)) {
System.out.println("dates are equal:" +date);
EventData eventBean = new EventData();
if (eventList.isSupportedField(Event.END)
&& event.countValues(Event.END) > 0) {
long end = event.getDate(Event.END, 0);
SimpleDateFormat sdform = new SimpleDateFormat(
"MMM dd, yyyy HH:mm");
SimpleDateFormat sdfTime = new SimpleDateFormat(
"HH:mm");
SimpleDateFormat sdfhr = new SimpleDateFormat("HH");
String dateString1 =sdform.formatLocal(end);
String timeString1 =sdfTime.formatLocal(end);
String hr = sdfhr.formatLocal(end);
eventBean.setStartHr(hour);
eventBean.setEndHr(hr);
eventBean.setStartTime(timeString);
eventBean.setEndTime(timeString1);
eventBean.setStartDate(dateString);
eventBean.setEndDate(dateString1);
// Dialog.alert("equal startdate" + dateString);
// Dialog.alert("equal end date"+ dateString1);
}
if (eventList.isSupportedField(Event.LOCATION)
&& event.countValues(Event.LOCATION) > 0) {
String location = event
.getString(Event.LOCATION, 0);
eventBean.setLocation(location);
// Dialog.alert("equal location"+ location);
}
if (eventList.isSupportedField(Event.SUMMARY)
&& event.countValues(Event.SUMMARY) > 0) {
String subject = event.getString(Event.SUMMARY, 0);
eventBean.setSummary(subject);
// Dialog.alert("equal subject" +subject);
}
eventBean.setUserDate(usrDate);
eventBean.setTimeZone(timezone);
listEvents.addElement(eventBean);
System.out.println("the size bf hashis"
+ listEvents.size());
for (int i = 0; i < listEvents.size();i++) {
EventData e = (EventData)listEvents.elementAt(i);
System.out.println("so thesummary is ::"
+ e.getSummary());
}
// for(int i=0;i<listUserEvents.size();i++){
if (listUserEvents.containsKey(usrDate)) {
// listUserEvents.remove(usrDate);
Vector info = (Vector)listUserEvents.get(usrDate);
System.out.println("the size in getEvents is"
+ info.size());
if(info.contains(usrDate)){
System.out.println("in info");
}
info.addElement(eventBean);
System.out.println("vector size info is"
+ info.size());
listUserEvents.put(usrDate,info);
} else {
System.out.println("in else of getevent" +listEvents.size());
listUserEvents.put(usrDate,listEvents);
}
// }
} else {
// Dialog.alert("not equal");
}
}
}
Device.setTimeZone(timeZoneEvent);
Calendar calendarLocalLastEvent = Calendar.getInstance();
// fetches time zone
TimeZone timeZoneEventLast =calendarLocalLastEvent.getTimeZone();
System.out.println("Time Zone last-->"
+ timeZoneEventLast.getDefault());
} catch (PIMException e) {
// //Dialog.alert(e.getMessage());
}
System.out.println("size in hashtable " + listUserEvents.size());
return listUserEvents;
}
它必须是这样的
for(int i = 0; i<listUserEvents.size();i++)
{
if (listUserEvents.containsKey(usrDate)){
listUserEvents.remove(usrDate);
}
}
它不能正常工作我已经在这里复制了整个函数http://codepad.org/6hFplePX – 2012-03-21 19:12:40
我在这里粘贴了代码 – 2012-03-21 19:15:04
你可以用main方法粘贴整个类吗？我认为这将有助于我和他人在主要职位 – bentham 2012-03-21 19:30:08
这里是如何工作的一个简单的例子：
Hashtable<String, Integer> numbers = new Hashtable<String, Integer>();
numbers.put("one", 1);
numbers.put("two", 2);
if (numbers.containsKey("two")) {
numbers.put("two", 222);
}
什么是你在遇到困难吗？另外你的钥匙是什么类型的？是java.util.Date还是别的？
散列表是类型（字符串向量
我有代码somethinh在http://codepad.org/6hFplePX，删除是给出例外 – 2012-03-21 19:05:53
我已粘贴码 – 2012-03-21 19:15:22
那么，无论你的散列表键是否必须是日期，或者你需要迭代所有的散列表条目。如果你想删除一个条目，使用'remove（key）'将其删除。 – 2012-03-21 18:24:32
你的问题不清楚。你在哪里面临这个问题？ – 2012-03-21 18:27:00
@HotLicks我已经使用删除（键），但它的功能工作，你可以请修改的代码段和示例 – 2012-03-21 18:29:49