Use RSA for File Encryption and Decryption in Java
“If you can’t do anything about it, laugh like hell.”
― David Cook
RSA (Rivest–Shamir–Adleman) is an asymmetric encryption algorithm widely used in public-key cryptography today. The word asymmetric denotes the use of a pair of keys for encryption – a public key and a private key. When data is encrypted by one key, it can only be decrypted using the other key. The public key is publicized and the private key is kept secret.
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Learn how to use AES for encryption and decryption in Java
“There’s as many atoms in a single molecule of your DNA as there are stars in the typical galaxy. We are, each of us, a little universe.” ― Neil deGrasse Tyson, Cosmos
The Advanced Encryption Standard (AES) is a standard for encryption and decryption that has been approved by the U.S. NIST (National Institute of Standards and Technology) in 2001. It is more secure than the previous encryption standard DES (Data Encryption Standard) and 3DES (Triple-DES). You should be using AES for all symmetric encryption needs in preference to DES and 3DES (which are now deprecated).
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Learn how to get details of columns in an SQL query with JDBC.
An earlier article covered the basics of JDBC (Java DataBase Connectivity) and how to perform SQL queries on a MySQL database. Frequently, it is useful to obtain more information about the columns in a query. These include: the number of columns, column names and types, etc. Maybe you want to build a GUI table showing the results of a query, which requires the names of the columns and more. This article will show you how to retrive the information using JDBC.
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A simple tutorial showing the basics of using JDBC database API.
“A man’s true character comes out when he’s drunk.”
― Charlie Chaplin
JDBC stands for Java DataBase Connectivity and is the standard API (application programming interface) java provides for working with databases. JDBC, as a standard, is built into the java platform. To connect with and use a database, you need an additional component called a jdbc driver, which is specific to the type of database you are working with, such as MySQL, SQL Server, etc. In other words, the JDBC API consists of a small number of classes and a bunch of interfaces, the implementation provided by the actual database vendor. This is illustrated by the figure below.
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Learn about the Python yield statement which is used to create generators.
“Count your age by friends, not years. Count your life by smiles, not tears.”
― John Lennon
Python provides an yield statement which allows you to create generator functions. What is a generator function and how does the yield statement help with it? Let us find out in this article.
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“Everything must be made as simple as possible. But not simpler.”
― Albert Einstein
Learn how to zip a folder in Java
“Quotation, n: The act of repeating erroneously the words of another.”
― Ambrose Bierce, The Unabridged Devil’s Dictionary
Java provides good support for reading and writing zip files. In this article, let us learn how to create a zip file from the contents of a folder in java.
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A Tutorial covering the basics of Java Calendar and Date Manipulation
“Let us tenderly and kindly cherish therefore, the means of knowledge. Let us dare to read, think, speak, and write .”
― John Adams
Java provides a Calendar class for performing data manipulation. A closely related class is the Date class, used to represent a specific instant in time starting from epoch (January 1, 1970 00:00:00.000 GMT). Let use learn how we can use these two classes for date and time manipulation.
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Learn the intricacies of Java Number to String Conversion and vice-versa.
“It is a good thing for an uneducated man to read books of quotations.”
― Winston S. Churchill
Number conversion is a frequent need while programming. You may have a need to convert from a hex string, decimal string or octal string. Or maybe you are using a number from a different base. The reverse conversion is also required many times: converting from a decimal integer to hex string, octal string, etc. Let us see how we can do these conversions.
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Learn the intricacies of using the Java Path API in this tutorial
“The mind is not a vessel to be filled, but a fire to be kindled.”
The Java Path API is a new introduction starting from version 1.7. It provides convenience methods for manipulating file paths in a system-independent way. Let us examine the usage of the Path API in more detail.
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