Reflectively invoke RowMetadata.getColumnMetadatas.

We now use reflection to call RowMetadata.getColumnMetadatas to avoid NoSuchMethodError when using R2DBC 0.9 as the return type has changed in newer R2DBC versions.

Closes #699

Author: mp911de

src/main/java/org/springframework/data/r2dbc/convert/MappingR2dbcConverter.java

@@ -647,7 +647,7 @@ private Object extractGeneratedIdentifier(Row row, RowMetadata metadata, String
 			return row.get(idColumnName);
 		}
 
-		Iterable<? extends ColumnMetadata> columns = metadata.getColumnMetadatas();
+		Iterable<? extends ColumnMetadata> columns = RowMetadataUtils.getColumnMetadata(metadata);
 		Iterator<? extends ColumnMetadata> it = columns.iterator();
 
 		if (it.hasNext()) {

src/main/java/org/springframework/data/r2dbc/convert/RowMetadataUtils.java

@@ -18,6 +18,11 @@
 import io.r2dbc.spi.ColumnMetadata;
 import io.r2dbc.spi.RowMetadata;
 
+import java.lang.reflect.Method;
+
+import org.springframework.lang.Nullable;
+import org.springframework.util.ReflectionUtils;
+
 /**
  * Utility methods for {@link io.r2dbc.spi.RowMetadata}
  *
@@ -26,6 +31,9 @@
  */
 class RowMetadataUtils {
 
+	private static final @Nullable Method getColumnMetadatas = ReflectionUtils.findMethod(RowMetadata.class,
+			"getColumnMetadatas");
+
 	/**
 	 * Check whether the column {@code name} is contained in {@link RowMetadata}. The check happens case-insensitive.
 	 *
@@ -35,12 +43,32 @@ class RowMetadataUtils {
 	 */
 	public static boolean containsColumn(RowMetadata metadata, String name) {
 
-		for (ColumnMetadata columnMetadata : metadata.getColumnMetadatas()) {
+		Iterable<? extends ColumnMetadata> columns = getColumnMetadata(metadata);
+
+		for (ColumnMetadata columnMetadata : columns) {
 			if (name.equalsIgnoreCase(columnMetadata.getName())) {
 				return true;
 			}
 		}
 
 		return false;
 	}
+
+	/**
+	 * Return the {@link Iterable} of {@link ColumnMetadata} from {@link RowMetadata}.
+	 *
+	 * @param metadata the metadata object to inspect.
+	 * @return
+	 * @since 1.4.1
+	 */
+	@SuppressWarnings("unchecked")
+	public static Iterable<? extends ColumnMetadata> getColumnMetadata(RowMetadata metadata) {
+
+		if (getColumnMetadatas != null) {
+			// Return type of RowMetadata.getColumnMetadatas was updated with R2DBC 0.9.
+			return (Iterable<? extends ColumnMetadata>) ReflectionUtils.invokeMethod(getColumnMetadatas, metadata);
+		}
+
+		return metadata.getColumnMetadatas();
+	}
 }