通过json schema将map转换为json字符串

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通过json schema将map转换为json字符串

name, year
1   , 1

Map<String, Object> map = new HashMap<>();
map.put("name", "1");
map.put("year", 1);
org.json.JSONObject obj = new org.json.JSONObject(map);
System.out.println(obj.toString());

{"year":1,"name":"1"}

// your map
Map<String, Object> map = new HashMap<>();
map.put("name", "1");
map.put("year", 1);
// create Gson instance
Gson gson = new GsonBuilder().create();
// convert to JSON
String jsonString = gson.toJson(map);
// convert back to map
Map map = gson.fromJson(jsonString, Map.class);

<dependency>
    <groupId>com.fasterxml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-csv</artifactId>
    <version>${jackson.version}</version>
</dependency>

@JsonPropertyOrder({"name", "year"})
public class Person {
    private String name;
    private Integer year;
    // Getters and setters   
}

CsvMapper mapper = new CsvMapper();
CsvSchema schema = mapper.schemaFor(Person.class).withHeader();
MappingIterator<Object> iterator = mapper.readerFor(Person.class)
        .with(schema).readValues(new FileInputStream("/path/to/the/csv/file"));
String json = new ObjectMapper().writeValueAsString(iterator.readAll());

name,year
test,38
foo,78

    try {
        File file = ResourceUtils.getFile(this.getClass().getResource("/import.csv"));
        List<List<String>> lines = new ArrayList<>();
        try (BufferedReader br = new BufferedReader(new FileReader(file))) {
            String line;
            while ((line = br.readLine()) != null) {
                String[] values = line.split(",");
                lines.add(Arrays.asList(values));
        Map<String,Integer> resultMap = new HashMap<>();
        for (int i = 1; i < lines.size(); i++) {
            List<String> currentLine = lines.get(i);
            String name = currentLine.get(0);
            String year = currentLine.get(1);
            if(StringUtils.isNoneEmpty(name,year) && StringUtils.isNumeric(year)){
                resultMap.put(name,Integer.valueOf(year));
        Gson gson = new GsonBuilder().create();
        String jsonString = gson.toJson(resultMap);
        System.out.println(jsonString);
    } catch (IOException e) {
        System.out.println(e);
    }

{"1":1,"test":38,"foo":78}

     public String generateJsonFromCSV() throws IOException {
        File csvFile = new File("path/to/csv/mycsv.csv");
        File schemaJson = new File("path/to/json/schema.json");
        Map<String, CsvSchema.ColumnType> map = getSchemaMapFromJson(schemaJson);
        CsvSchema.Builder schemaBuilder = new CsvSchema.Builder();
        map.forEach(schemaBuilder::addColumn);
        CsvSchema schema = schemaBuilder.build();
        CsvMapper csvMapper = new CsvMapper();
        MappingIterator<Map<?, ?>> mappingIterator = csvMapper.readerFor(Map.class).with(schema).readValues(csvFile);
        String json = new ObjectMapper().writeValueAsString(mappingIterator.readAll());
        return json;
    //Convert your JsonSchema to Map<String,CsvSchema.ColumnType>
    private Map<String, CsvSchema.ColumnType> getSchemaMapFromJson(File file) {

通过json schema将map转换为json字符串

5 个回答