解决FileInputStream读取ANSI格式txt中文乱码问题

解决FileInputStream读取ANSI格式txt中文乱码问题

GBK中文转为byte后以负数开头，正常来说为连续两个负数，生僻字可能为一个负数和一个整数，所以需要特殊处理一下
注：utf-8的txt一个中文占三个byte数组，故此方法不适用

import java.io.FileInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Arrays;

public class FileInputStreamTest03 {
    public static void main(String[] args) {
        // test
        String s = "中c国Dh丄";
        byte[] bs = new byte[10];
        try {
            bs = s.getBytes("GBK");
            System.out.println(Arrays.toString(bs));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        String s2 = null;
        try {
            s2 = new String(bs, "GBK");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        System.out.println(s2);
        // main
        FileInputStream fp = null;
        try {
            fp = new FileInputStream("C:\\Users\\dell\\Documents\\a代码备份\\python\\爬虫\\bilibili\\list.txt");
            byte[] b = new byte[10];
            int num;
            while ((num = fp.read(b)) != -1){
                int pos = 0; // 记录负值个数，中文GBK为两个负值
                for (byte b1 : b) {
                    if (b1 < 0){
                        pos++;
                    }
                }
                // System.out.println(Arrays.toString(b));
                if (pos%2 != 0 && b[b.length-1] < 0){
                    int nextValue=fp.read();
                    int size = b.length;
                    int nextLen=size+1;
                    //字节数组扩容一位
                    b = Arrays.copyOf(b,nextLen);
                    b[size]= (byte) nextValue;
                    String content=new String(b, 0, nextLen, "GBK");
                    System.out.print(content);
                } else {
                    System.out.print(new String(b, 0, num, "GBK"));
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (fp != null){
                try {
                    fp.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}