Introduction and usage of Apache Commons CSV framework

Introduction and usage of Apache Commons CSV framework Apache Commons CSV is an open source Java library that is used to analyze and operate the CSV (comma segmental value) file.It is a project of the Apache Software Foundation, which provides a simple and efficient method to read and write into the CSV file. CSV is a commonly used data format that is used to store table data.It consists of a text line, and each row is composed of several fields. The fields are separated by comma.CSV files are suitable for various applications, such as data export, data conversion, and simple data storage. Apache Commons CSV provides the following main functions: 1. Read the CSV file: You can easily read the CSV file through the CSVPARSER class.You can set the separators, reference symbols, and rotation characters, and read the content of the files by routine or iteration. The following is an example code for reading CSV files: Reader reader = new FileReader("input.csv"); CSVParser parser = new CSVParser(reader, CSVFormat.DEFAULT); for (CSVRecord record : parser) { String value1 = record.get(0); String value2 = record.get(1); // Process CSV record data } parser.close(); 2. Write to CSV file: You can write data to the CSV file through the CSVPrinter class.You can set the separators, reference symbols, and rotary characters, and can be written into the files one by one or iteratively. The following is an example code written to the CSV file: Writer writer = new FileWriter("output.csv"); CSVPrinter printer = new CSVPrinter(writer, CSVFormat.DEFAULT); printer.printRecord("Value1", "Value2"); printer.printRecord("Data1", "Data2"); // Add more records printer.close(); 3. CSV format definition: Apache Commons CSV also provides a CSVFormat class to define the format of CSV files.You can set separation symbols, reference symbols, rotary characters, and head information. The following is a sample code that defines the CSV file format: CSVFormat format = CSVFormat.DEFAULT .withDelimiter(',') .withQuote('"') .withEscape('\\') .withHeader("Header1", "Header2"); Apache Commons CSV also supports more advanced features, such as processing irregular CSV files, processing large CSV files and custom parsers. Summarize: Apache Commons CSV is a convenient and easy -to -use Java library for analysis and operation of CSV files.It provides a simple way to read and write CSV files, and supports the definition of multiple CSV file formats.Whether you conduct data analysis, export or conversion of CSV files, Apache Commons CSV is a tool worth using. I hope this article will help you understand the introduction and usage how to understand the Apache Commons CSV framework.If necessary, you can refer to the official documentation to learn more functions and example code. Reference link: [Apache Commons CSV official document] (https://commons.apache.org/proper/commons- CSV/)