listoffiles.java

java应用开发详解

import java.util.*;
import java.io.*;

//实现了枚举类接口
public class ListOfFiles implements Enumeration 
{

    private String[] listOfFiles;
    private int current = 0;

    public ListOfFiles(String[] listOfFiles) 
    {
        this.listOfFiles = listOfFiles;
    }

    public boolean hasMoreElements() 
    {
        if (current < listOfFiles.length)
            return true;
        else
            return false;
    }

    public Object nextElement() 
    {
        InputStream in = null;

        if (!hasMoreElements())
            throw new NoSuchElementException("No more files.");
        else 
        {
            String nextElement = listOfFiles[current];
            current++;
            try 
            {
                in = new FileInputStream(nextElement);
            } 
            catch (FileNotFoundException e) 
            {
                System.err.println("ListOfFiles: Can't open " + nextElement);
            }
        }
        return in;
    }
}