What Is NIO? In NIO, we deal with channels and buffers for I/O operations. A channel, like a stream represents a connection between a data source/sink and a Java program for data transfer. A channel provides a two-way data transfer facility. We can use a channel to read data as well as to…

JAR API JAR API includes classes for working with a manifest file. An object of the Manifest class represents a manifest file. You create a Manifest object in your code as follows: Manifest manifest = new Manifest(); We can read entries from a manifest file and write entries to it. To add…

Manifest File A JAR file may optionally contain a manifest file named MANIFEST.MF in the META-INF directory. The manifest file contains information about the JAR file and its entries. A manifest file can contain information about the CLASSPATH setting for the JAR file, and its main entry class. The main entry class…

JAR File Format JAR (Java Archive) is a file format based on the ZIP file format. It is used to bundle resources, class files, sound files, images, etc. for a Java application or applet. It also provides data compression. A JAR file as a special kind of a ZIP file. You can digitally…

Java has direct support for the ZIP file format. Typically, we would be using the following four classes from the java.util.zip package to work with the ZIP file format: ZipEntry ZipInputStream ZipOutputStream ZipFile A ZipEntry object represents an entry in an archive file in a ZIP file format. A zip…

Checksum Java provides an Adler32 class in the java.util.zip package to compute the Adler-32 checksum for bytes of data. We need to call the update() method of this class to pass bytes to it. There is also another class named CRC32 in the same package, which lets you compute a checksum…

We define the sequence of characters that are considered tokens by defining delimiter characters. The StringTokenizer class is in the java.util package. The StreamTokenizer class is in the java.io package. A StringTokenizer breaks a string into tokens whereas a StreamTokenizer gives we access to the tokens in a character-based stream. StringTokenizer …

To read numbers from the standard input, we have to read it as a string and parse it to a number. The Scanner class in java.util package reads and parses a text, based on a pattern, into primitive types and strings. The text source can be an InputStream, a file…

The purpose of the Console class is to make the interaction between a Java program and the console easier. The Console class is a utility class in the java.io package that gives access to the system console. The console is not guaranteed to be accessible in a Java program on…