/** Verify that using a ByteArrayInputStream does not allocate a new byte array. */
@Test
public void testByteArrayInputStream() throws Exception {
byte[] bytes = new byte[8];
InputStream input = new ByteArrayInputStream(bytes);
try {
byte[] bytesRead = StreamUtil.getBytesFromStream(input);
assertTrue(Arrays.equals(bytes, bytesRead));
} finally {
Closeables.close(input, true);
}
}
/** Verify that using an offset with ByteArrayInputStream still produces correct output. */
@Test
public void testByteArrayInputStreamWithOffset() throws Exception {
byte[] bytes = new byte[] {0, 1, 2, 3, 4};
InputStream input = new ByteArrayInputStream(bytes, 1, 4);
try {
byte[] bytesRead = StreamUtil.getBytesFromStream(input);
byte[] expectedBytes = new byte[] {1, 2, 3, 4};
assertTrue(Arrays.equals(expectedBytes, bytesRead));
} finally {
Closeables.close(input, true);
}
}
@Test
public void testSuccessfulSkip() throws Exception {
InputStream inputStream = mock(InputStream.class);
when(inputStream.skip(anyLong())).thenReturn(2L);
assertEquals(10, StreamUtil.skip(inputStream, 10));
InOrder order = inOrder(inputStream);
order.verify(inputStream).skip(10);
order.verify(inputStream).skip(8);
order.verify(inputStream).skip(6);
order.verify(inputStream).skip(4);
order.verify(inputStream).skip(2);
verifyNoMoreInteractions(inputStream);
}
@Test
public void testUnsuccessfulSkip() throws Exception {
InputStream inputStream = mock(InputStream.class);
when(inputStream.skip(anyLong())).thenReturn(3L, 5L, 0L, 6L, 0L);
when(inputStream.read()).thenReturn(3, -1);
assertEquals(15, StreamUtil.skip(inputStream, 20));
InOrder order = inOrder(inputStream);
order.verify(inputStream).skip(20);
order.verify(inputStream).skip(17);
order.verify(inputStream).skip(12);
order.verify(inputStream).read();
order.verify(inputStream).skip(11);
order.verify(inputStream).skip(5);
order.verify(inputStream).read();
verifyNoMoreInteractions(inputStream);
}
private void checkFileInputStream(int size) throws IOException {
byte[] bytesToWrite = new byte[size];
for (int i = 0; i < size; i++) {
bytesToWrite[i] = (byte) i; // It's okay to truncate
}
File tmpFile = File.createTempFile("streamUtil", "test");
InputStream input = null;
OutputStream output = null;
try {
output = new FileOutputStream(tmpFile);
output.write(bytesToWrite);
output.close();
input = new FileInputStream(tmpFile);
byte[] bytesRead = StreamUtil.getBytesFromStream(input);
assertTrue(Arrays.equals(bytesToWrite, bytesRead));
} finally {
Closeables.close(input, true);
Closeables.close(output, false);
assertTrue(tmpFile.delete());
}
}