### Question:
GzipUtil { public static byte[] decompress(byte[] bytes) { if (bytes == null) { throw new NullPointerException("bytes is null"); } ByteArrayOutputStream out = new ByteArrayOutputStream(); try (GZIPInputStream gunzip = new GZIPInputStream(new ByteArrayInputStream(bytes))) { byte[] buffer = new byte[BUFFER_SIZE]; int n; while ((n = gunzip.read(buffer)) > -1) { out.write(buffer, 0, n); } return out.toByteArray(); } catch (IOException e) { throw new RuntimeException("gzip decompress error", e); } } private  GzipUtil(); static byte[] compress(byte[] bytes); static byte[] decompress(byte[] bytes);  }### Answer:
@Test public void test_decompress() { Assertions.assertThrows(NullPointerException.class, () -> { GzipUtil.decompress(null); }); Assertions.assertThrows(RuntimeException.class, () -> { GzipUtil.decompress(new byte[0]); }); Assertions.assertThrows(RuntimeException.class, () -> { byte[] bytes = {0x1, 0x2}; GzipUtil.decompress(bytes); }); }