java io 读取写文件

java 读取txt文件，汉字乱码，原因是因为文件的编码格式和程序编码采用了不同的编码格式。通常，假如自己不修改的话，windows自身采用的编码格式是gbk(而gbk和gb2312基本上是一样的编码方式)，程序中一般采用utf-8,所以读取文件的时候最好指定编码方式

方式1：以字节流读写

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.Writer;

import org.apache.commons.lang3.StringUtils;

public class FileReadWriteDemo2 {

    public static void main(String[] args) throws IOException {

        BufferedReader read = new BufferedReader(new InputStreamReader(new FileInputStream("f:/test.txt"),"gbk"));
        Writer out = new OutputStreamWriter(new FileOutputStream("f:/testNew.txt"),"gbk");
        BufferedWriter writer =new BufferedWriter(out);
        String fileContent ="";
        String line = "";
        while ((line = read.readLine()) != null) {
            //删除空格
            if (StringUtils.isNotBlank(line)) {
                //System.out.println(line);
                fileContent +=line+"\r\n";
                writer.write(line);
                writer.write("\r\n");
            }
        }
        read.close();
        writer.close();
        System.out.println(fileContent);
    }
}

方式2：以字符流读写

public class FileReadWriteDemo {

    public static void main(String[] args) throws IOException {
        BufferedReader read = new BufferedReader(new FileReader("f:\\test.txt"));

        BufferedWriter writer = new BufferedWriter(new FileWriter("f:/testNew.txt"));

        String line = "";
        while ((line = read.readLine()) != null) {

            if (StringUtils.isNotBlank(line)) {
                System.out.println(line);
                writer.write(line);
                writer.write("\n ");
            }
        }
        read.close();
        writer.close();
    }
}