java如何存csv

在Java中存储CSV，你可以采用以下四种主要方法：1.使用FileWriter和BufferedWriter、2.使用Apache Commons CSV、3.使用OpenCSV、4.使用Super CSV。在这篇文章中，我们将对这四种方法进行详细的探讨，并提供相关的代码示例。

一、使用FileWriter和BufferedWriter

这是最基本的方式，只需要Java的核心库。首先，你需要创建一个FileWriter对象，然后使用BufferedWriter将数据写入文件。这种方法简单易用，但可能需要更多的代码行来处理更复杂的CSV数据。

import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
public class CSVWriterExample {
    private static final String CSV_FILE_PATH = "./csvExample.csv";
    public static void main(String[] args) {
        try (BufferedWriter writer = new BufferedWriter(new FileWriter(CSV_FILE_PATH))) {
            String[] entries = {"first", "second", "third"};
            for (String entry : entries) {
                writer.write(entry);
                writer.write(",");
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

二、使用Apache Commons CSV

Apache Commons CSV 是一个用于读取和写入CSV文件的Java库。它提供了一些高级功能，例如支持不同的CSV格式（如RFC4180、MySQL等），可以处理带引号的输入等。

import org.apache.commons.csv.CSVFormat;
import org.apache.commons.csv.CSVPrinter;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
public class ApacheCommonsCSVExample {
    private static final String CSV_FILE_PATH = "./csvExample.csv";
    public static void main(String[] args) {
        try (BufferedWriter writer = new BufferedWriter(new FileWriter(CSV_FILE_PATH));
             CSVPrinter csvPrinter = new CSVPrinter(writer, CSVFormat.DEFAULT.withHeader("ID", "Name", "Designation", "Company"))) {
            csvPrinter.printRecord("1", "John Doe", "Manager", "ABC Corp");
            csvPrinter.printRecord("2", "Jane Doe", "Developer", "XYZ Corp");
            csvPrinter.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

三、使用OpenCSV

OpenCSV 也是一个用于处理CSV文件的Java库。它提供了读取和写入CSV文件的简单接口，同时还支持自定义分隔符、引号字符和转义字符。

import com.opencsv.CSVWriter;
import java.io.FileWriter;
import java.io.IOException;
public class OpenCSVExample {
    private static final String CSV_FILE_PATH = "./csvExample.csv";
    public static void main(String[] args) {
        try (CSVWriter writer = new CSVWriter(new FileWriter(CSV_FILE_PATH))) {
            String[] entries = {"first", "second", "third"};
            writer.writeNext(entries);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

四、使用Super CSV

Super CSV 是一个功能强大的CSV文件处理库，它支持读写CSV文件，并提供了丰富的数据处理和校验功能。

import org.supercsv.cellprocessor.constraint.NotNull;
import org.supercsv.cellprocessor.ift.CellProcessor;
import org.supercsv.io.CsvBeanWriter;
import org.supercsv.io.ICsvBeanWriter;
import org.supercsv.prefs.CsvPreference;
import java.io.FileWriter;
import java.io.IOException;
public class SuperCSVExample {
    private static final String CSV_FILE_PATH = "./csvExample.csv";
    public static void main(String[] args) {
        try (ICsvBeanWriter beanWriter = new CsvBeanWriter(new FileWriter(CSV_FILE_PATH), CsvPreference.STANDARD_PREFERENCE)) {
            final String[] header = {"first", "second", "third"};
            final CellProcessor[] processors = getProcessors();
            beanWriter.writeHeader(header);
            beanWriter.write(new MyBean("firstValue", "secondValue", "thirdValue"), header, processors);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    private static CellProcessor[] getProcessors() {
        final CellProcessor[] processors = new CellProcessor[]{
                new NotNull(), // first
                new NotNull(), // second
                new NotNull() // third
        };
        return processors;
    }
    public static class MyBean {
        private String first;
        private String second;
        private String third;
        public MyBean(String first, String second, String third) {
            this.first = first;
            this.second = second;
            this.third = third;
        }
        // getters and setters omitted
    }
}

这些只是在Java中存储CSV的几种方式，具体的选择取决于你的需求和项目的复杂性。

java如何存csv

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