[Smhi] Ensure trailing zeroes are removed before updating channels (#11353)

* Ensure unnecessary trailing zeroes are removed, to avoid issues with transformations.

Signed-off-by: Anders Alfredsson <andersb86@gmail.com>

* Change to use setScale()

Signed-off-by: Anders Alfredsson <andersb86@gmail.com>

bundles/org.openhab.binding.smhi/src/main/java/org/openhab/binding/smhi/internal/SmhiHandler.java

@@ -15,6 +15,7 @@ package org.openhab.binding.smhi.internal;
 import static org.openhab.binding.smhi.internal.SmhiBindingConstants.*;
 
 import java.math.BigDecimal;
+import java.math.RoundingMode;
 import java.time.ZoneOffset;
 import java.time.ZonedDateTime;
 import java.util.ArrayList;
@@ -218,7 +219,7 @@ public class SmhiHandler extends BaseThingHandler {
                     newState = new QuantityType<>(value.get(), MetricPrefix.MILLI(SIUnits.METRE));
                     break;
                 default:
-                    newState = new DecimalType(value.get());
+                    newState = new DecimalType(value.get().setScale(0, RoundingMode.DOWN));
             }
         }
 

bundles/org.openhab.binding.smhi/src/test/java/org/openhab/binding/smhi/internal/SmhiTest.java

@@ -18,12 +18,14 @@ import static org.openhab.binding.smhi.internal.SmhiBindingConstants.*;
 import java.io.IOException;
 import java.io.InputStream;
 import java.math.BigDecimal;
+import java.math.RoundingMode;
 import java.time.ZonedDateTime;
 
 import org.eclipse.jdt.annotation.NonNullByDefault;
 import org.eclipse.jdt.annotation.Nullable;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
+import org.openhab.core.library.types.DecimalType;
 
 /**
  * @author Anders Alfredsson - Initial contribution
@@ -101,7 +103,8 @@ public class SmhiTest {
         assertEquals(0, pcat0.compareTo(BigDecimal.valueOf(0)));
         assertEquals(0, pmean0.compareTo(BigDecimal.valueOf(0)));
         assertEquals(0, pmedian0.compareTo(BigDecimal.valueOf(0)));
-        assertEquals(0, wsymb0.compareTo(BigDecimal.valueOf(2)));
+        assertEquals(0, wsymb0.compareTo(BigDecimal.valueOf(20)));
+        assertEquals("20", new DecimalType(wsymb0.setScale(0, RoundingMode.DOWN)).toString());
 
         Forecast forecast1 = timeSeries1.getForecast(TIME.plusHours(1), 0).orElseThrow(AssertionError::new);