java读取txt文件

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;

public class ClassInfoSort {

  public static void main(String[] args) {
    reader();
  }
  public static void reader() {
    File file = new File("test.txt");
    FileInputStream fin = null;
    try {
      fin = new FileInputStream(file);
      byte[] b = new byte[fin.available()];
      fin.read(b);
      String str = new String(b,"UTF-8");
      System.out.println(str);
    } catch (FileNotFoundException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      try {
        fin.close();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
    
  }
}