Java CsvMapper.writer方法代码示例

import com.fasterxml.jackson.dataformat.csv.CsvMapper; //导入方法依赖的package包/类
@Setup(Level.Iteration)
public void setUp() {
    dsl = CsvWriter.from(SmallBenchmarkObject.class).skipHeaders();
    sbo = new SmallBenchmarkObject();
    sbo.setId(2);
    sbo.setEmail("[email protected]");
    sbo.setName("name");
    sbo.setYearStarted(222);

    CsvMapper mapper = new CsvMapper();
    CsvSchema schema = mapper.schemaFor(SmallBenchmarkObject.class);


    myObjectWriter = mapper.writer(schema);

    settings = new CsvWriterSettings();
    settings.setHeaders("id", "year_started", "name", "email");
    settings.setRowWriterProcessor(new BeanWriterProcessor<SmallBenchmarkObject>(SmallBenchmarkObject.class));

}
 

import com.fasterxml.jackson.dataformat.csv.CsvMapper; //导入方法依赖的package包/类
/**
 * Creates a Jackson object writer based on a mapper. Has a special handling
 * for CSV media types.
 * 
 * @return The Jackson object writer.
 */
protected ObjectWriter createObjectWriter() {
    ObjectWriter result = null;

    if (MediaType.TEXT_CSV.isCompatible(getMediaType())) {
        CsvMapper csvMapper = (CsvMapper) getObjectMapper();
        CsvSchema csvSchema = createCsvSchema(csvMapper);
        result = csvMapper.writer(csvSchema);
    } else {
        result = getObjectMapper().writerFor(getObjectClass());
    }

    return result;
}
 

import com.fasterxml.jackson.dataformat.csv.CsvMapper; //导入方法依赖的package包/类
public void generateCsvReport(List<ZeroCodeCsvReport> zeroCodeCsvReportRows) {

        /*
         * Write to a CSV file
         */
        CsvSchema schema = CsvSchema.builder()
                .setUseHeader(true)
                .addColumn("scenarioName")
                .addColumn("scenarioLoop", CsvSchema.ColumnType.NUMBER)
                .addColumn("stepName")
                .addColumn("stepLoop", CsvSchema.ColumnType.NUMBER)
                .addColumn("correlationId")
                .addColumn("requestTimeStamp")
                .addColumn("responseTimeStamp")
                .addColumn("responseDelayMilliSec", CsvSchema.ColumnType.NUMBER)
                .addColumn("result")
                .build();

        CsvMapper csvMapper = new CsvMapper();
        csvMapper.enable(CsvParser.Feature.WRAP_AS_ARRAY);

        ObjectWriter writer = csvMapper.writer(schema.withLineSeparator("\n"));
        try {
            writer.writeValue(
                    new File(TARGET_FULL_REPORT_DIR +
                            TARGET_FULL_REPORT_CSV_FILE_NAME +
                            "_" +
                            LocalDateTime.now().toString().replace(":", "-") +
                            ".csv"),
                    zeroCodeCsvReportRows);

        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException("Exception while Writing full CSV report. Details: " + e);
        }
    }
 

import com.fasterxml.jackson.dataformat.csv.CsvMapper; //导入方法依赖的package包/类
public static void main(String[] args) {

        List<User> users = new ArrayList<>();
        User userHeader = new User("First", "Last", "Age");
        User user1 = new User("First name1", "Last Name1", null);
        User user2 = new User("First name2", "Last Name2", "22");
        users.add(userHeader);
        users.add(user1);
        users.add(user2);

        CsvSchema schema = CsvSchema.builder()
                .addColumn("firstName")
                .addColumn("lastName")
                .addColumn("age", CsvSchema.ColumnType.NUMBER)
                //.addColumn("comments")
                //.setUseHeader(true)
                //.setStrictHeaders(false)
                .build();

//        CsvSchema bootstrapSchema = CsvSchema.emptySchema().withHeader();
//        ObjectMapper mapper = new CsvMapper();

        CsvMapper mapper = new CsvMapper();
        mapper.enable(CsvParser.Feature.WRAP_AS_ARRAY);

        ObjectWriter writer = mapper.writer(schema.withLineSeparator("\n"));
        try {
            writer.writeValue(new File("target/ModifiedUsers.csv"), users);
        } catch (IOException e) {
            e.printStackTrace();
        }

    }
 

import com.fasterxml.jackson.dataformat.csv.CsvMapper; //导入方法依赖的package包/类
private ObjectWriter buildWriter(boolean includeWeight) {
    CsvMapper csvMapper = new CsvMapper();
    Class<? extends JsonBiasModellingDiseaseOccurrence> type =
        includeWeight ? JsonModellingDiseaseOccurrence.class : JsonBiasModellingDiseaseOccurrence.class;
    return csvMapper.writer(csvMapper.schemaFor(type).withHeader());
}
 

import com.fasterxml.jackson.dataformat.csv.CsvMapper; //导入方法依赖的package包/类
private static void writeCsvResult(final FileIoStats stats) {
  if (params.getResultCsvFile() == null) {
    return;
  }

  final Object[] results = new Object[] {
      new Date().toGMTString(),
      params.getNumFiles(),
      params.getNumThreads(),
      params.getReplication(),
      params.getBlockSize(),
      params.getIoSize(),
      stats.getFilesWritten(),
      stats.getBytesWritten(),
      stats.getMeanCreateTimeMs(),
      stats.getMeanWriteTimeMs(),
      stats.getMeanCloseTimeMs(),
      stats.getElapsedTimeMs(),
      (params.getFileSize() * 1000) / stats.getElapsedTimeMs(),
      (params.getNumFiles() * params.getFileSize() * 1000) /
          stats.getElapsedTimeMs(),
      params.getNote()
  };

  final CsvSchema schema = CsvSchema.builder()
      .setColumnSeparator(';')
      .setQuoteChar('"')
      .setUseHeader(!params.getResultCsvFile().exists())
      .addColumn("timestamp", CsvSchema.ColumnType.STRING)
      .addColumn("number of files", CsvSchema.ColumnType.NUMBER)
      .addColumn("number of threads", CsvSchema.ColumnType.NUMBER)
      .addColumn("replication factor", CsvSchema.ColumnType.NUMBER)
      .addColumn("block size", CsvSchema.ColumnType.NUMBER)
      .addColumn("io size", CsvSchema.ColumnType.NUMBER)
      .addColumn("total files written", CsvSchema.ColumnType.NUMBER)
      .addColumn("total bytes written", CsvSchema.ColumnType.NUMBER)
      .addColumn("mean time to create file in ms", CsvSchema.ColumnType.NUMBER)
      .addColumn("mean time to write file in ms", CsvSchema.ColumnType.NUMBER)
      .addColumn("mean time to close file in ms", CsvSchema.ColumnType.NUMBER)
      .addColumn("total ms", CsvSchema.ColumnType.NUMBER)
      .addColumn("mean throughput bytes per s", CsvSchema.ColumnType.NUMBER)
      .addColumn("aggregate throughput bytes per s", CsvSchema.ColumnType.NUMBER)
      .addColumn("note", CsvSchema.ColumnType.STRING)
      .build();

  try (FileWriter fileWriter = new FileWriter(params.getResultCsvFile(), true)) {
    final CsvMapper mapper = new CsvMapper();
    final ObjectWriter writer = mapper.writer(schema);
    writer.writeValue(fileWriter, results);
  } catch (IOException e) {
    LOG.error("Could not write results to CSV file '{}': '{}'",
        params.getResultCsvFile().getPath(), e.getMessage());
  }
}