Find a File in a Directory and Subdirectories in Java
Find a file in a directory and its subdirectories in Java with Files.find(), Files.walk() and walkFileTree(), with depth limits and globs.
Java FileWriter: Constructors, Append Mode and Charset
Java FileWriter explained with constructors, write and append methods, append mode, the UTF-8 default since Java 18, flush, close and the alternatives.
Java InputStreamReader: Decode Bytes to Text With a Charset
Java InputStreamReader decodes bytes from an InputStream into characters. Learn charsets, read methods, malformed input, closing rules and alternatives.
Java FileReader: Constructors, Charset and Examples
Learn the Java FileReader class with UTF-8 charset constructors, char[] and line reading, error handling and when to use Files.newBufferedReader instead.
List All Files in a Directory in Java (list, walk, find)
List all files in a directory in Java with Files.list, Files.walk, Files.find and DirectoryStream, incl. recursion, filters by extension and errors.
Unzip a File in Java with Subdirectories (Zip Slip Safe)
Unzip a file in Java with ZipFile or ZipInputStream, extract subdirectories, block zip slip and zip bombs, and read archives as a zip file system.
Java BufferedReader: readLine(), lines() and LineNumberReader
Java BufferedReader examples for readLine(), lines(), mark and reset, buffer size and console input, plus LineNumberReader for line numbers in errors.
How to Read a Properties File in Java (and Write It Back)
Learn to read a properties file in Java with load(), write it with store(), load from the classpath, use defaults, update safely and handle UTF-8.
Java Base64 Encode and Decode (Basic, URL-Safe and MIME)
Java Base64 encode and decode examples with java.util.Base64 for strings, URL-safe tokens, MIME email, files and streams, plus fixes for decoding errors.
Java IO vs NIO: Differences and When to Use Each (Java 25)
Java IO vs NIO compared for Java 25. Streams vs buffers, blocking vs selectors, NIO.2 Files and Path, virtual threads, and a table of which API to use.