Favourite tutorials for developers
In previous article, we show how to compress a file in Gzip format. This article shows how to decompress a Gzip file. We copy the GZIPInputStream into a FileOutputStream to decompress a Gzip file. Instead, we can use NIO File.copy to copy a file. Also we can decompress a Gzip file into a byte[] directly without saving it into a local file.
This article shows how to convert an object to byte[] or byte array and vice versa in Java. The example show how to use ByteArrayOutputStream and ObjectOutputStream to convert an object to byte[]. The example show how to use ByteArrayInputStream and ObjectInputStream to convert byte[] back to an object.
This article shows a few ways to save a byte[] into a file. For JDK 1.7 and above, the NIO Files.write is the simplest solution to save byte[] to a file. FileOutputStream is the best alternative. If we have Apache Commons IO, try FileUtils.
In Java, we can use Files.readAllBytes(path) to convert a File object into a byte[]. Before Java 7, we can initiate a new byte[] with a predefined size (same with the file length), and use FileInputStream to read the file data into the new byte[]. We also can use FileUtils from Apache Commons IO to read the file.
In Java, we can use ByteArrayInputStream to convert a String to an InputStream. We will examine how to use ByteArrayInputStream to convert a String to an InputStream and saves it into a file.
This article shows a few ways to convert an java.io.InputStream to a String. We will examine a few ways: using ByteArrayOutputStream, using InputStream#readAllBytes (Java 9), using InputStreamReader + StringBuilder, InputStreamReader + BufferedReader, using Java 8 BufferedReader#lines, using Apache Commons IO.
In Java, we can use str.getBytes(StandardCharsets.UTF_8) to convert a String into a byte[]. And we can use new String(bytes, StandardCharsets.UTF_8) to convert byte[] to a String.
In Java, we can use new String(bytes, StandardCharsets.UTF_8) to convert a byte[] to a String. For text or character data, we use new String(bytes, StandardCharsets.UTF_8) to convert the byte[] to a String directly. However, for cases that byte[] is holding the binary data like the image or other non-text data, the best practice is to convert the byte[] into a Base64 encoded string.
This article shows you a few ways to convert byte arrays or byte[] to a hexadecimal (base 16 or hex) string representative. String.format, Integer.toHexString, Apache Commons Codec – commons-codec, Spring Security Crypto – spring-security-crypto, Bitwise shifting and masking. (educational purposes)
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