code: @Test public void poolSingleHttpConnection() throws IOException {
    ConnectionPool pool=new ConnectionPool(1,KEEP_ALIVE_DURATION_MS);
    Connection connection=pool.get(httpAddress);
    assertNull(connection);
    connection=new Connection(null,new Route(httpAddress,Proxy.NO_PROXY,httpSocketAddress,true));
    connection.connect(200,200,null);
    assertEquals(0,pool.getConnectionCount());
    pool.recycle(connection);
    assertEquals(1,pool.getConnectionCount());
    assertEquals(1,pool.getHttpConnectionCount());
    assertEquals(0,pool.getSpdyConnectionCount());
    Connection recycledConnection=pool.get(httpAddress);
    assertEquals(connection,recycledConnection);
    assertTrue(recycledConnection.isAlive());
    recycledConnection=pool.get(httpAddress);
    assertNull(recycledConnection);
  }
  