Added a helper method to return the version

Author: egonw

org.bridgedb/src/main/java/org/bridgedb/BridgeDb.java

@@ -16,8 +16,11 @@
 //
 package org.bridgedb;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Properties;
 
 /**
  * Central access point for connecting to IDMappers.
@@ -69,4 +72,23 @@ public static void register(String protocol, Driver driver)
 	{
 		drivers.put(protocol, driver);
 	}
+
+    private static volatile String version;
+
+    /**
+     * Returns the version of BridgeDb.
+     */
+    public static String getVersion() {
+        if (version != null) return version;
+        try (InputStream stream = BridgeDb.class.getResourceAsStream("/version.props")) {
+            Properties props = new Properties();
+            props.load(stream);
+            version = props.getProperty("bridgedb.version");
+            return version;
+        } catch (IOException exception) {
+            exception.printStackTrace();
+        }
+        return null;
+    }
+
 }

org.bridgedb/src/test/java/org/bridgedb/BridgeDbTest.java

@@ -0,0 +1,26 @@
+/* Copyright (c) 2025 Egon Willighagen <egonw@users.sf.net>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and limitations under the License.
+ */
+package org.bridgedb;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.junit.jupiter.api.Test;
+
+public class BridgeDbTest {
+
+	@Test
+	public void testVersion() {
+		String version = BridgeDb.getVersion();
+		assertNotNull(version);
+		assertTrue(version.startsWith("3."));
+	}
+}