java获取文件编码方式

1. 引入依赖

  
        <dependency>
            <groupId>com.github.jiangxincodegroupId>
            <artifactId>cpdetectorartifactId>
            <version>1.0.10version>
        dependency>

2. 工具类

import info.monitorenter.cpdetector.io.*;

import java.io.*;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;

public class ReadUtil {
    public static List<String> readFile(String filePath){//filePath为文件路径，charset为字符编码。通常使用UTF-8
        List<String> res = new ArrayList<>();
        File file = new File(filePath);
        String charset = getCharsetName(file)
        BufferedReader reader = null;
        String tempString = null;
        StringBuffer str = new StringBuffer();
        try {
            InputStreamReader isr = new InputStreamReader(new FileInputStream(file), charset);
            reader = new BufferedReader(isr);
            while ((tempString = reader.readLine()) != null) {
                res.add(tempString);
            }
            reader.close();
        } catch (FileNotFoundException e) {
            System.out.println("文件不存在");
            return null;
        } catch (IOException e) {
            System.out.println("文件读取异常");
            return null;
        }
        return res;
    }
    /**
     * 获取文件编码方式
     */
    public static String getCharsetName(File file) throws IOException {
        String charsetName = "UTF-8";
        CodepageDetectorProxy detector = CodepageDetectorProxy.getInstance();
        detector.add(new ParsingDetector(false));
        detector.add(JChardetFacade.getInstance());
        detector.add(ASCIIDetector.getInstance());
        detector.add(UnicodeDetector.getInstance());
        Charset charset = detector.detectCodepage(file.toURI().toURL());
        if (charset != null) charsetName = charset.name();
        return charsetName;
    }


    public static void main(String[] args) throws IOException {
        File file = new File("D:\\testDirs\\data\\test.dat");
        System.out.println(getCharsetName(file));

    }
}