import java.io.*;
import java.util.*;
class Student implements Comparable<Student>
{
  private String name;
  private int ma,cn,en;
  private int sum;
  Student(String name,int ma,int cn,int en)
  {
   this.name=name;
   this.ma=ma;
   this.cn=cn;
   this.en=en;
   sum=ma+cn+en;
  }
  
  public int compareTo(Student s)
  {
   int num=new Integer(this.sum).compareTo(new Integer(s.sum));
   if (num==0)
    return this.name.compareTo(s.name);
   return num;
  }
  public String getName()
  {
   return name;
  }
  public int getSum()
  {
   return sum;
  }
  public int hashCode()
  {
   return name.hashCode()+sum*78;
  }
  public boolean equals(Object obj)
  {
   if(!(obj instanceof Student))
    throw new ClassCastException("类型不匹配");
   Student s=(Student)obj;
   return this.name.equals(s.name)&&this.sum==s.sum;
  }
  public String toString()
  {
   return "Student["+name+", "+ma+", "+cn+", "+en+"]";
  }
}
class StudentInfoTool
{
public static Set<Student> getStudents()throws IOException
{
  return getStudents(null);
}
public static Set<Student> getStudents(Comparator<Student> cmp)throws IOException
{
  BufferedReader bufr=new BufferedReader(new InputStreamReader(System.in));
  String line=null;
  Set<Student> stus=null;
  if(cmp==null)
   stus=new TreeSet<Student>();
  else
   stus=new TreeSet<Student>(cmp);
  while((line=bufr.readLine())!=null)
  {
   if("over".equals(line))
    break;
   String[] info=line.split(",");
   Student stu=new Student(info[0],Integer.parseInt(info[1]),
            Integer.parseInt(info[2]),
            Integer.parseInt(info[3]));
   stus.add(stu);
  }
  bufr.close();
  return stus;
}
public static void writeFile(Set<Student> stus)throws IOException
{
  BufferedWriter bufw=new BufferedWriter(new FileWriter("stuinfo.txt"));
  for (Student stu: stus)
  {
   bufw.write(stu.toString()+"\t");
   bufw.write(stu.getSum()+"");
   bufw.newLine();
   bufw.flush();
  }
  bufw.close();
}
}
class StudentInfoTest
{
public static void main(String[] args)throws IOException
{
  Comparator<Student> cmp=Collections.reverseOrder();
  //Set<Student> stus=StudentInfoTool.getStudents();
  Set<Student> stus=StudentInfoTool.getStudents(cmp);
  StudentInfoTool.writeFile(stus);
}
}

这段代码在Editplus能够编译和运行通过，怎么放在eclipse上就不能编译呢?

BufferedWriter bufw=new BufferedWriter(new FileWriter("stuinfo.txt"));
是不是没有指定路径呀？

是不是你eclipse的Java Compiler设定的版本太低了？