Check out example codes for "write input stream to file java". It will help you in understanding the concepts better.

Code Example 1

InputStream pdf = // greate some input stream data
try (FileOutputStream outputStream = new FileOutputStream(new File("/Users/kirkbrown/documents/my.pdf"))) {

			int read;
			byte[] bytes = new byte[1024];

			while ((read = pdf.read(bytes)) != -1) {
				outputStream.write(bytes, 0, read);
			}
		}

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