Java，CSV转换为json，jackson-dataformat-csv

Question

I am novice in java and I want to convert csv file into json

I'am using the following code example to convert csv file into json file, the things is, I have got an error on the" withSchema(bootstrap) " it says : "The method with(CsvSchema) is undefined for the type ObjectReader" and I do not know how to fix it, I have change maven dependencies to the version 2.9.0, try withtype(bootstrap) withCsvSchema(bootstap) but still not working .

Thanks

Here is the code :

package CsvData;

import java.io.File;
import java.io.IOException;
import java.util.List;
import java.util.Map;

import com.fasterxml.jackson.databind.MappingIterator;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.dataformat.csv.CsvMapper;
import com.fasterxml.jackson.dataformat.csv.CsvSchema;

public class csvjson {

    public static void main(String[] args) throws Exception {
        File input = new File("/x/data.csv");
        File output = new File("/x/data.json");

        List<Map<?, ?>> data = readObjectsFromCsv(input);
        writeAsJson(data, output);
    }

    public static List<Map<?, ?>> readObjectsFromCsv(File file) throws IOException {
        CsvSchema bootstrap = CsvSchema.emptySchema().withHeader();
        CsvMapper csvMapper = new CsvMapper();
        MappingIterator<Map<?, ?>> mappingIterator = csvMapper.reader(Map.class).with(bootstrap).readValues(file);

        return mappingIterator.readAll();
    }

    public static void writeAsJson(List<Map<?, ?>> data, File file) throws IOException {
        ObjectMapper mapper = new ObjectMapper();
        mapper.writeValue(file, data);
    }
}

Answer 1

正确的方法名称为withSchema

csvMapper.reader(Map.class).withSchema(bootstrap).readValues(file);

Answer 2

I tried with version 2.2.1 and it works fine for me.

<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-csv</artifactId>
<version>2.2.1</version>

Here is the Java method

public static List<Map<?, ?>> readObjectsFromCsv(File file) throws IOException {
    CsvSchema bootstrap = CsvSchema.emptySchema().withHeader();
    CsvMapper csvMapper = new CsvMapper();
    MappingIterator<Map<?, ?>> mappingIterator = csvMapper.reader(Map.class).with(bootstrap).readValues(file);

    return  mappingIterator.readAll();
}

Even document says it works since 2.2 but dnt know why it is not working for 2.9.0.