static void checkClosed(TestCloseable... closeables) {
            for (TestCloseable closeable : closeables)
                assertTrue(closeable.closed, "Close not invoked for " + closeable.id);
        }
Expectation setter for multiple reads where each one reads random bytes to the buffer.

@param channelMock           The mocked FileChannel object
@param bufferSize            The buffer size
@return Expected buffer string
@throws IOException          If an I/O error occurs
clients/src/test/java/org/apache/kafka/common/utils/UtilsTest.java