test: Added tests for VideoCapture constructors in java

modules/videoio/misc/java/test/VideoCaptureTest.java

@@ -35,10 +35,30 @@ public class VideoCaptureTest extends OpenCVTestCase {
         assertFalse(capture.isOpened());
     }
 
-    public void testVideoCapture() {
+    public void testDefaultConstructor() {
         capture = new VideoCapture();
         assertNotNull(capture);
         assertFalse(capture.isOpened());
     }
 
+    public void testConstructorWithFilename() {
+        capture = new VideoCapture("some_file.avi");
+        assertNotNull(capture);
+    }
+
+    public void testConstructorWithFilenameAndExplicitlySpecifiedAPI() {
+        capture = new VideoCapture("some_file.avi", Videoio.CAP_ANY);
+        assertNotNull(capture);
+    }
+
+    public void testConstructorWithIndex() {
+        capture = new VideoCapture(0);
+        assertNotNull(capture);
+    }
+
+    public void testConstructorWithIndexAndExplicitlySpecifiedAPI() {
+        capture = new VideoCapture(0, Videoio.CAP_ANY);
+        assertNotNull(capture);
+    }
+
 }