Added check to ensure that only dividend transactions have an ex-date

Issue: #5439

Author: buchen

name.abuchen.portfolio/META-INF/services/name.abuchen.portfolio.checks.Check

@@ -14,3 +14,4 @@ name.abuchen.portfolio.checks.impl.FixWrongTransfersCheck
 name.abuchen.portfolio.checks.impl.FixDepositsWithSecurityCheck
 name.abuchen.portfolio.checks.impl.NegativeExchangeRateCheck
 name.abuchen.portfolio.checks.impl.MissingTransactionDateCheck
+name.abuchen.portfolio.checks.impl.OnlyDividendsCanHaveExDateCheck

name.abuchen.portfolio/src/name/abuchen/portfolio/checks/impl/OnlyDividendsCanHaveExDateCheck.java

@@ -0,0 +1,31 @@
+package name.abuchen.portfolio.checks.impl;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import name.abuchen.portfolio.checks.Check;
+import name.abuchen.portfolio.checks.Issue;
+import name.abuchen.portfolio.model.AccountTransaction;
+import name.abuchen.portfolio.model.Client;
+
+public class OnlyDividendsCanHaveExDateCheck implements Check
+{
+    @Override
+    public List<Issue> execute(Client client)
+    {
+        var answer = new ArrayList<Issue>();
+
+        for (var account : client.getAccounts())
+        {
+            for (var tx : account.getTransactions())
+            {
+                if (tx.getExDate() != null && tx.getType() != AccountTransaction.Type.DIVIDENDS)
+                {
+                    tx.setExDate(null);
+                }
+            }
+        }
+
+        return answer;
+    }
+}