How to map csv file to pojo class in java

问题

I am using java maven plugin.I want to fetch employee.csv file records in pojo class. this pojo class I am generating from employee.csv header and all fields of pojo class are String type.now I want to map employee.csv to generated pojo class.my requirement is I dont want to specify column names manually.because if I change csv file then again I have to chane my code so it should dynamically map with any file. for instance

firstName,lastName,title,salary 
john,karter,manager,54372

I want to map this to pojo which I have already

public class Employee
{
  private String firstName;
  private String lastName;
  .
  .
  //getters and setters 
  //toString()
}

回答1:

uniVocity-parsers allows you to map your pojo easily.

class Employee {

    @Trim
    @LowerCase
    @Parsed
    private String firstName;

    @Parsed
    private String lastName;

    @NullString(nulls = { "?", "-" }) // if the value parsed in the quantity column is "?" or "-", it will be replaced by null.
    @Parsed(defaultNullRead = "0") // if a value resolves to null, it will be converted to the String "0".
    private Integer salary; // The attribute name will be matched against the column header in the file automatically.
    ...

}

To parse:

BeanListProcessor<Employee> rowProcessor = new BeanListProcessor<Employee>(Employee.class);

CsvParserSettings parserSettings = new CsvParserSettings();
parserSettings.setRowProcessor(rowProcessor);
parserSettings.setHeaderExtractionEnabled(true);

CsvParser parser = new CsvParser(parserSettings);

//And parse!
//this submits all rows parsed from the input to the BeanListProcessor
parser.parse(new FileReader(new File("/path/to/your.csv"))); 

List<Employee> beans = rowProcessor.getBeans();

Disclosure: I am the author of this library. It's open-source and free (Apache V2.0 license).

回答2:

you can use openCSV jar to read the data and then you can map the each column values with the class attributes. Due to security reason, i can not share my code with you.

来源：https://stackoverflow.com/questions/33886120/how-to-map-csv-file-to-pojo-class-in-java

标签

java

csv

mapping

pojo