Java中文件的读写

利用StringBuffer写入文字到txt

public class Iotest {

StringBuffer sb;
BufferedReader br;

public void write() throws IOException{

//尽量使用File类中的常量File.separator “//”的意思

File file=new File("D:"+File.separator+"buffer.txt");
if(!file.exists()){
file.createNewFile();
}
FileOutputStream out=new FileOutputStream(file);    
for(int i=0;i<10;i++){
StringBuffer sb=new StringBuffer();
             sb.append("这是第"+i+"行:前面介绍的各种方法都不关用,为什么总是奇怪的问题 ");
out.write(sb.toString().getBytes("utf-8"));
//输入换行符
String newLine = System.getProperty("line.separator");
out.write(newLine.toString().getBytes());

}
out.close();

}

利用BufferedReader一行一行读出

public void read() throws IOException{
File file=new File("d://buffer.txt");
br=new BufferedReader(new InputStreamReader(new FileInputStream(file),"utf-8"));
String line;
while((line=br.readLine())!=null){
System.out.println(line);
}
}

public static void main(String []a) throws IOException{
new Iotest().read();

}