Category: Java Sample Practices

Java – Convert Excel File to/from JSON (String/File) – using Apache Poi + Jackson

In the tutorial, Grokonez shows how to convert Excel File to JSON String or JSON File and vice versa with Java language by examples.

– Excel Files: Microsoft Excel is a spreadsheet developed by Microsoft for Windows, macOS, Android and iOS. It features calculation, graphing tools, pivot tables, and a macro programming language called Visual Basic for Applications (VBA). It has been a very widely applied spreadsheet for these platforms
– JSON stands for JavaScript Object Notation. JSON is a lightweight format for storing and transporting data. JSON is often used when data is sent from a server to a web page.

Continue reading “Java – Convert Excel File to/from JSON (String/File) – using Apache Poi + Jackson”

Java – Convert CSV File to/from JSON (String/File) – using Commons-CSV + Jackson

In the tutorial, Grokonez shows how to convert CSV File to JSON String or JSON File and vice versa with Java language by examples.

Continue reading “Java – Convert CSV File to/from JSON (String/File) – using Commons-CSV + Jackson”

Java – iText Write/Read PDF File Example – PdfReader + PdfWriter

In the tutorial, we show how to Write/Read PDF File with iText library.

Continue reading “Java – iText Write/Read PDF File Example – PdfReader + PdfWriter”

Compress String with Run Length Encoding in Java

In this Java example, we’re gonna know how to compress String in Java with Run Length Encoding (RLE) method.

Related Posts:
– Java Regular Expression Overview – Syntax
– Java Regular Expression to extract data from a Text
– Java Regular Expression to mask information from a Text

Continue reading “Compress String with Run Length Encoding in Java”

Balanced Tree – AVL Tree in Java

In this tutorial, we’re gonna look at AVL Tree Data Structure. It is a balanced binary search tree – the heights of given node’s children trees don’t differ more than 1 (with height of node = max of its children node + 1).

balanced-tree-avl-tree-java-overview

Continue reading “Balanced Tree – AVL Tree in Java”