Added BatchMessageTest for https://issues.redhat.com/browse/JGRP-2788

tests/junit-functional/org/jgroups/tests/BatchMessageTest.java

@@ -0,0 +1,57 @@
+package org.jgroups.tests;
+
+import org.jgroups.*;
+import org.jgroups.util.ByteArray;
+import org.jgroups.util.ByteArrayDataInputStream;
+import org.jgroups.util.MyReceiver;
+import org.jgroups.util.Util;
+import org.testng.annotations.Test;
+
+import java.io.DataInput;
+import java.nio.ByteBuffer;
+
+/**
+ * Tests {@link BatchMessage}
+ * @author Bela Ban
+ * @since  5.3.7, 5.4
+ */
+@Test(groups=Global.FUNCTIONAL)
+public class BatchMessageTest extends MessageTestBase {
+    protected static final Address SRC=Util.createRandomAddress("X"), DEST=Util.createRandomAddress("A");
+    protected static final Message M1=create(DEST, 10, false, false);
+    protected static final Message M2=create(DEST, 1000, true, true);
+    protected static final Message M3=new EmptyMessage(DEST);
+
+    protected static final MessageFactory MF=new DefaultMessageFactory();
+
+    public void testCreation() {
+        BatchMessage msg=new BatchMessage(DEST, SRC, new Message[]{M1,M2,M3}, 3);
+        assert msg.getNumberOfMessages() == 3;
+        assert msg.getLength() == M1.getLength() + M2.getLength() + M3.getLength();
+    }
+
+    /** https://issues.redhat.com/browse/JGRP-2788 */
+    public void testSendMulticast() throws Exception {
+        try(JChannel a=new JChannel(Util.getTestStack()).name("A");
+            JChannel b=new JChannel(Util.getTestStack()).name("B")) {
+            MyReceiver<Message> r1=new MyReceiver<Message>().rawMsgs(true);
+            MyReceiver<Message> r2=new MyReceiver<Message>().rawMsgs(true);
+            a.connect(BatchMessageTest.class.getSimpleName());
+            b.connect(BatchMessageTest.class.getSimpleName());
+            Util.waitUntilAllChannelsHaveSameView(2000, 100, a,b);
+            BatchMessage msg=new BatchMessage(DEST, SRC, new Message[]{M1,M2,M3}, 3);
+            a.send(msg);
+            Util.waitUntil(2000, 100, () -> r1.size() == 1 && r2.size() == 1);
+        }
+
+    }
+
+
+    protected static Message create(Address dest, int length, boolean nio, boolean direct) {
+        if(!nio)
+            return new BytesMessage(dest, new byte[length]).setSrc(SRC);
+        return direct? new NioMessage(dest, ByteBuffer.allocateDirect(length)).setSrc(SRC) :
+          new NioMessage(dest, ByteBuffer.allocate(length)).setSrc(SRC);
+    }
+
+}