feat: Add better API to configure maximum allowed rows (#12466)

* feat: Add better API to configure maximum allowed rows

* Add unit test

Co-authored-by: Olli Tietäväinen <ollit@vaadin.com>

2 files changed, 22 insertions, 4 deletions

diff --git a/server/src/main/java/com/vaadin/data/provider/DataCommunicator.java b/server/src/main/java/com/vaadin/data/provider/DataCommunicator.java
index 8d974c85d3..097cef622d 100644
--- a/server/src/main/java/com/vaadin/data/provider/DataCommunicator.java
+++ b/server/src/main/java/com/vaadin/data/provider/DataCommunicator.java
@@ -60,7 +60,7 @@ import elemental.json.JsonObject;
 public class DataCommunicator<T> extends AbstractExtension {
 
     private Registration dataProviderUpdateRegistration;
-    private static final int MAXIMUM_ALLOWED_ROWS = 500;
+    private int maximumAllowedRows = 500;
 
     /**
      * Simple implementation of collection data provider communication. All data
@@ -316,14 +316,24 @@ public class DataCommunicator<T> extends AbstractExtension {
     }
 
     /**
-     * Set the maximum allowed rows to be fetched in one query.
+     * Get the maximum allowed rows to be fetched in one query.
      * 
      * @return Maximum allowed rows for one query.
      * @since 8.14.1
      */
     protected int getMaximumAllowedRows() {
-        return MAXIMUM_ALLOWED_ROWS;
-    }    
+        return maximumAllowedRows;
+    }
+
+    /**
+     * Set the maximum allowed rows to be fetched in one query.
+     * 
+     * @param maximumAllowedRows Maximum allowed rows for one query.
+     * @since
+     */
+    public void setMaximumAllowedRows(int maximumAllowedRows) {
+        this.maximumAllowedRows = maximumAllowedRows;
+    }
 
     /**
      * Triggered when rows have been dropped from the client side cache.
diff --git a/server/src/test/java/com/vaadin/data/provider/DataCommunicatorTest.java b/server/src/test/java/com/vaadin/data/provider/DataCommunicatorTest.java
index ed681f298d..fda867eeef 100644
--- a/server/src/test/java/com/vaadin/data/provider/DataCommunicatorTest.java
+++ b/server/src/test/java/com/vaadin/data/provider/DataCommunicatorTest.java
@@ -322,4 +322,12 @@ public class DataCommunicatorTest {
         communicator.onRequestRows(0, communicator.getMaximumAllowedRows() + 10,
                 0, 0);
     }
+
+    @Test
+    public void requestTooMuchRowsOverride() {
+        TestDataCommunicator communicator = new TestDataCommunicator();
+        int maxRows = communicator.getMaximumAllowedRows();
+        communicator.setMaximumAllowedRows(maxRows + 100);
+        communicator.onRequestRows(0, maxRows + 10, 0, 0);
+    }
 }