/**
* 字符流,每次读取/写入一行
* BufferedReader/PrintWriter
* @Author: www.itze.cn
* @Date: 2020/9/28 10:29
* @Email: 814565718@qq.com
* @param srcFile
* @param destFile
*/
public static void brAndpw(String srcFile,String destFile){
try {
BufferedReader reader = new BufferedReader(new FileReader(srcFile));
//参数说明,第二个true时,写入的时候会自动刷新,就不需要刷新了
PrintWriter writer = new PrintWriter(new FileOutputStream(destFile), true);
String str = null;
//读取,每次读取一行
while ((str=reader.readLine())!=null){
//写入,println:写入并自动换行,print:写入但是不执行换行
writer.println(str);
}
reader.close();
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}

使用方法

public static void main(String[] args) {
String srcFile = "D:\\newCountry.txt";
String destFile = "D:\\newCountry2.txt";
brAndpw(srcFile,destFile);
}