facing problem with List iteration in drools
GoodsShipment has the list of GoodsItems and
GoodsItem has the list of Documents
my requirement is, need to check atleast one document is available or no.
iam tried this
but failed
writen a class to checking purpose
public class CheckDocument {
public boolean flag = false;
public CheckPreviousDocument() {
}
public boolean getPreviousDocument(GoodsShipment goodsshipment) {
List<GoodsItem> list = goodsshipment.getGoodsItems();
Iterator<GoodsItem> itr = list.iterator();
while (itr.hasNext()) {
GovernmentAgencyGoodsItem document = itr.next();
if (document.getDocuments().size() > 0) {
flag = true;
break;
}
}
return flag;
}
}
rule "previousDocuments minimum 1"
when
$o: GoodsShipment()
%x: CheckPreviousDocuments(previousDocuments($o) == false)
then
insert(-------------)
end
can anyone please help me..
thanks in advance
Your code is somewhat unusual, but thus rule should do. Note that I have used Document as the type for the elements in the list returned by GovernmentAgencyGoodsItem.getDocuments().
rule atLeastOne
when
$gs: GoodsShipment()
List( size > 0 )
from accumulate ( $gi: GoodsItem() from $gs.getGoodsItems() and
$d: Document() from $gi.getDocuments();
collectList( $d ) )
then
// $gs contains at least one Document
end
Related
I don't understand why how HashSet works in this question
Here's the link to this problem https://leetcode.com/problems/two-sum-iv-input-is-a-bst/
Here's the solution to this problem
the codes are
public class Solution {
public boolean findTarget(TreeNode root, int k) {
Set < Integer > set = new HashSet();
Queue < TreeNode > queue = new LinkedList();
queue.add(root);
while (!queue.isEmpty()) {
if (queue.peek() != null) {
TreeNode node = queue.remove();
if (set.contains(k - node.val))
return true;
set.add(node.val);
queue.add(node.right);
queue.add(node.left);
} else
queue.remove();
}
return false;
}
}
Why we need to declare another HashSet for this problem? Do we put all the tree node in the hashset? Why this step is not shown in the code?
Also, since we didn't explicitly put any value in the set, how can we code for "set. contains()"? Am I missing some basics for hashset?
From the code, we simply traversed the tree using an extra queue and then we add the valid value/answer into the hashset. But we only need to return the boolean answer for this question. Thats why I am confused.
I am new to RxJava2.
I am trying to get a list of Transaction object both from cache and from server.
I want to compare the server value to cache value and if the server value is the same, then ignore it.
I was able to do it easily using .scan() because we can return null and when null is returned from the .scan() the value got ignored(filtered).
RxJava 1
private Observable<List<Transaction>> getTransactionsFromCacheAndServer() {
return Observable.concat(
getTransactionsFromCache(),
getTransactionsFromServer()
)
.scan((p1, p2) -> {
if (p1 == null && p2 != null) {
return p2;
} else if (p1 != null && !isListSame(p1, p2)) {
return p2;
} else {
return null;
}
});
}
With RxJava 2, since I cannot return null anymore, things are not easy.
RxJava 2
private Observable<List<Transaction>> getTransactionsFromCacheAndServer() {
return Observable.concat(
getTransactionsFromCache(),
getTransactionsFromServer()
)
.map(FilterObject::new)
.scan((filterObject1, filterObject2) -> {
List<Transaction> p1 = (List<Transaction>)filterObject1.value;
List<Transaction> p2 = (List<Transaction>)filterObject2.value;
if (p1.size() == 0 && p2.size() > 0) {
return filterObject2;
} else if (!isListSame(p1, p2)) {
return filterObject2;
} else {
filterObject2.filter = true;
return filterObject2;
}
})
.filter(filterObject -> !filterObject.filter)
.map(filterObject -> (List<Transaction>)filterObject.value);
}
Where FilterObject is:
public class FilterObject {
public Object value;
public boolean filter;
public FilterObject(Object value) {
this.value = value;
}
}
Even though I can achieve the same thing using above method, it seems very ugly. Also I had to include two maps which might not be so performance friendly.
Is there a simple/clean way to achieve what I want?
I don't think there is a generic solution to this problem, since an empty list and a list that needs to be filtered (which happens to be empty in all cases) are two different things (the output of the scan) and needs to be handled differently.
However, in your particular case you never emit an empty list, except maybe for the first output.
(I am using String instead Transaction, shouldn't matter)
private Observable<List<String>> getTransactionsFromCacheAndServer() {
return Observable.concat(
getTransactionsFromCache(),
getTransactionsFromServer()
)
.filter(list -> !list.isEmpty())
// If you prefer a consistent empty list over the first
// empty list emission getting filtered
.startWith((List<String>) Collections.EMPTY_LIST)
// Newly emitted value cannot be empty, it only depends only on the comparison
.distinctUntilChanged(this::isListSame);
}
That's the closest I could get with as few operators as possible. Hope it solves your problem.
Based on andras' answer, I modified little bit to achieve what I want.
private Observable<List<String>> getTransactionsFromCacheAndServer() {
return Observable.concat(
getTransactionsFromCache(),
getTransactionsFromServer()
)
.filter(list -> !list.isEmpty())
.distinctUntilChanged(this::isListSame)
.switchIfEmpty(Observable.just(new ArrayList<>()));
}
Andreas' answer will always receive an empty list and then a real data.
My solution above will receive:
1. Data from cache (and then data from server if different)
2. Empty list if both cache and server returns Empty list.
I am trying to look up record using if I have the key then use Find if not use Where
private ApplicationDbContext db = new ApplicationDbContext();
public bool DeactivatePrice(int priceId = 0, string sponsorUserName = "")
{
var prices = db.BeveragePrices;
// if we have an id then find
if (priceId != 0)
{
prices = prices.Find(priceId);
}
else
{
prices = prices.Where(b => b.UserCreated == sponsorUserName);
}
if (prices != null)
{
// do something
}
return true;
I get the following error for
prices = prices.Find(priceId);
Cannot convert app.Model.BeveragePrices from system.data.entity.dbset
I am copying the pattern from this answer but something must be different.
Seems you forgot to put a predicate inside the Find function call. Also you need to do ToList on the collection. The second option is a lot more efficient. The first one gets the whole collection before selection.
Another note commented by #Alla is that the find returns a single element. So I assume another declaration had been made for 'price' in the first option I state down here.
price = prices.ToList.Find(b => b.PriceId == priceId);
Or
prices = prices.Select(b => b.PriceId == priceId);
I assume the field name is PriceId.
i have an app which has btn to preview report made in crystal report. I added Dataset as datasource of the report and dragged datatable from the toolbox and added the fields I need as columns. I got the instruction from this link http://aspalliance.com/2049_Use_LINQ_to_Retrieve_Data_for_Your_Crystal_Reports.2. This is my 2nd report the first one works and did not encounter any prob at all that is why i am confused, not to mention it also has nullable column. the error says: DataSet does not support System.Nullable<>.
private void ShowReportView()
{
string reportFile = "JudgeInfoFMReport.rpt";
ObservableCollection<tblJudgeFileMaint> judgeFileMaintList;
judgeFileMaintList = GenerateReport();
if (judgeFileMaintList.Count > 0)
{
CrystalReportViewerUC crview2 = new CrystalReportViewerUC();
crview2.SetReportPathFile(reportFile, judgeFileMaintList);
crview2.ShowDialog();
}
else
{
System.Windows.MessageBox.Show("No record found.", module, MessageBoxButton.OK, MessageBoxImage.Information);
}
}
private ObservableCollection<tblJudgeFileMaint> GenerateReport()
{
var result = FileMaintenanceBusiness.Instance.GetAllJudgeInfoList();
return new ObservableCollection<tblJudgeFileMaint>(result);
}
The error is in the part where I set datasource report.SetDataSource
public bool SetReportPathFile(string reportPathFile, IEnumerable enumerable)
{
string reportFolder = #"\CrystalReportViewer\Reports\";
string filename = System.Windows.Forms.Application.StartupPath + reportFolder + reportPathFile; // "\\Reports\\CrystalReports\\DateWiseEmployeeInfoReport.rpt";
ReportPathFile = filename;
report.Load(ReportPathFile);
report.SetDataSource(enumerable);
report.SetDatabaseLogon("sa", "admin007");
bRet = true;
}
_IsLoaded = bRet;
return bRet;
}
I read some answers and says I should set the null value to DBNUll which I did in the properties window of each column if it is nullable. Can anyone help me please? thanks
Your question can be seen in this post, but in a generic way ... that way you can pass an Object to a DataSet typed!
.NET - Convert Generic Collection to DataTable
figured it out. by using a collectionextention, copied somewhere, I forgot the link. Os to whoever it is who made the class, credits to you.
class method looks like this.
public statis class CollectionExtension {
public static DataSet ToDataSet<T>(this IEnumerable<T> collection, string dataTableName)
{
if (collection == null)
{
throw new ArgumentNullException("collection");
}
if (string.IsNullOrEmpty(dataTableName))
{
throw new ArgumentNullException("dataTableName");
}
DataSet data = new DataSet("NewDataSet");
data.Tables.Add(FillDataTable(dataTableName, collection));
return data;
}
}
then you can use it by doing this in getting your source to your report:
private DataSet GenerateNeutralContEducReport(string dsName)
{
var contEduHistoryList = FileMaintenanceBusiness.Instance.GetManyNeutralFMContEducHistoryInfobyKeyword(CurrentNeutralFM.NeutralID, "NeutralID").ToList();
return CollectionExtensions.ToDataSet<tblContinuingEducationHistory>(contEduHistoryList, dsName);
}
I found little help from the other proposed answers but this solution worked.
A different way to solve this problem is to make the data column nullable.
DataColumn column = new DataColumn("column", Type.GetType("System.Int32"));
column.AllowDBNull = true;
dataTable.Columns.Add(column);
https://learn.microsoft.com/en-us/dotnet/api/system.data.datacolumn.allowdbnull?view=netcore-3.1
foreach (PropertyDescriptor property in properties)
{
dt.Columns.Add(property.Name, Nullable.GetUnderlyingType(property.PropertyType) ?? property.PropertyType);
}
So how does one obtain the previous value of a custom field in a Jira IssueEventListener? I am writing a custom handler for the issueUpdated(IssueEvent) event and I would like to alter the handler's behavior if a certain custom field has changed. To detect the type of change I would like to compare the previous and current values.
(I'm am not asking about how to obtain its current value - I know how to get that from the related Issue)
I am developing against Jira 4.0.2 on Windows.
Is the best way to scan the change history for the last known value?
List changes = changeHistoryManager.getChangeHistoriesForUser(issue, user);
I'm assuming the original poster is writing a JIRA plugin with Java. I cannot be certain of how to accomplish this task in JIRA v4.0.2, but here is how I managed to do so with JIRA v5.0.2 (the solutions may very well be the same):
public void workflowEvent( IssueEvent event )
{
Long eventTypeId = event.getEventTypeId();
if( eventTypeId.equals( EventType.ISSUE_UPDATED_ID ) )
{
List<GenericValue> changeItemList = null;
try
{
changeItemList = event.getChangeLog().getRelated( "ChildChangeItem" );
}
catch( GenericEntityException e )
{
// Error or do what you need to do here.
e.printStackTrace();
}
if( changeItemList == null )
{
// Same deal here.
return;
}
Iterator<GenericValue> changeItemListIterator = changeItemList.iterator();
while( changeItemListIterator.hasNext() )
{
GenericValue changeItem = ( GenericValue )changeItemListIterator.next();
String fieldName = changeItem.get( "field" ).toString();
if( fieldName.equals( customFieldName ) ) // Name of custom field.
{
Object oldValue = changeItem.get( "oldvalue" );
Object newValue = changeItem.get( "newvalue" );
}
}
}
}
Some possible key values for changeItem are:
newvalue
oldstring
field
id
fieldtype
newstring
oldvalue
group
For many of the custom field types Object oldValue is probably just a String. But I don't think that's true for every case.
Try this example :
String codeProjetOldValue= "";
List<GenericValue> changeItemList = issueEvent.getChangeLog().getRelated("ChildChangeItem");
for (GenericValue genericValue : changeItemList) {
if(champCodeProjet.equals(genericValue.get("field"))){
codeProjetOldValue=genericValue.getString("oldstring");
break;
}
}
Note that : champCodeProjet is the name of customfield.