Adding test of windows generator with masking

jetty-websocket/websocket-core/src/test/java/org/eclipse/jetty/websocket/protocol/GeneratorTest.java

@@ -5,6 +5,8 @@ import static org.hamcrest.Matchers.*;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
 
+import org.eclipse.jetty.util.BufferUtil;
+import org.eclipse.jetty.websocket.api.WebSocketPolicy;
 import org.junit.Assert;
 import org.junit.Test;
 
@@ -43,4 +45,71 @@ public class GeneratorTest
         Assert.assertThat("Created Parts",totalParts,is(expectedParts));
         Assert.assertThat("Created Bytes",totalBytes,is(payload.length + expectedHeaderSize));
     }
+
+    @Test
+    public void testWindowedGenerateWithMasking()
+    {
+        byte payload[] = new byte[10240];
+        Arrays.fill(payload,(byte)0x55);
+
+        byte mask[] = new byte[]
+                { 0x2A, (byte)0xF0, 0x0F, 0x00 };
+
+        WebSocketFrame frame = WebSocketFrame.binary(payload);
+        frame.setMask(mask);
+
+        int totalParts = 0;
+        int totalBytes = 0;
+        int windowSize = 2929; // important, use an odd # window size to test masking across window barriers
+        int expectedHeaderSize = 8;
+        int expectedParts = (int)Math.ceil((double)(payload.length + expectedHeaderSize) / windowSize);
+
+        // Buffer to capture generated bytes
+        ByteBuffer completeBuf = ByteBuffer.allocate(payload.length + expectedHeaderSize);
+        BufferUtil.clearToFill(completeBuf);
+
+        // Generate and capture generator output
+        Generator generator = new UnitGenerator();
+
+        boolean done = false;
+        while (!done)
+        {
+            Assert.assertThat("Too many parts",totalParts,lessThan(20));
+
+            ByteBuffer buf = generator.generate(windowSize,frame);
+            // System.out.printf("Generated buf.limit() = %,d%n",buf.limit());
+
+            totalBytes += buf.remaining();
+            totalParts++;
+
+            BufferUtil.put(buf,completeBuf);
+
+            done = (frame.remaining() <= 0);
+        }
+
+        Assert.assertThat("Created Parts",totalParts,is(expectedParts));
+        Assert.assertThat("Created Bytes",totalBytes,is(payload.length + expectedHeaderSize));
+
+        // Parse complete buffer.
+        WebSocketPolicy policy = WebSocketPolicy.newServerPolicy();
+        Parser parser = new Parser(policy);
+        FrameParseCapture capture = new FrameParseCapture();
+        parser.setIncomingFramesHandler(capture);
+
+        BufferUtil.flipToFlush(completeBuf,0);
+        parser.parse(completeBuf);
+
+        // Assert validity of frame
+        WebSocketFrame actual = capture.getFrames().get(0);
+        Assert.assertThat("Frame.opcode",actual.getOpCode(),is(OpCode.BINARY));
+        Assert.assertThat("Frame.payloadLength",actual.getPayloadLength(),is(payload.length));
+
+        // Validate payload content for proper masking
+        ByteBuffer actualData = actual.getPayload().slice();
+        Assert.assertThat("Frame.payload.remaining",actualData.remaining(),is(payload.length));
+        while (actualData.remaining() > 0)
+        {
+            Assert.assertThat("Actual.payload[" + actualData.position() + "]",actualData.get(),is((byte)0x55));
+        }
+    }
 }