San Song Daddy :): How to Write&Read csv file in Java?

How to Write&Read csv file in Java?

By Errong Leng – 27 Apr 2023 – View online →

use OpenCSV

OpenCSV is able to serialize .csv files into preset and reusable schemas implemented as annotated Java pojo beans

<!-- https://mvnrepository.com/artifact/com.opencsv/opencsv -->  <dependency>      <groupId>com.opencsv</groupId>      <artifactId>opencsv</artifactId>      <version>5.7.1</version>  </dependency>

Write CSV

	StringWriter stringWriter = new StringWriter();
	try (CSVWriter csvWriter = new CSVWriter(stringWriter)) {
	// Define the CSV headers
	csvWriter.writeNext(headers);

	// Loop through each data and write as one record to the CSV
	datas.stream().map(Data::toCSVLine)
	.forEach(csvWriter::writeNext);

	stringWriter.flush();
	csvWriter.flush();
	stringWriter.close();
	return stringWriter.toString().getBytes();
	} catch (IOException exception) {
	throw new RuntimeException(exception.getCause());
	}

view raw OpenCSVWritter.java hosted with ❤ by GitHub

Read CSV

	CSVReader reader = new CSVReader(new InputStreamReader(new ByteArrayInputStream(users)));
	String[] values;
	List<String[]> records = new ArrayList<>();
	while ((values = reader.readNext()) != null) {
	records.add(values);
	}
	reader.close();