android平台上的文件下载,文件和文件的操作

android平台上对文件的操作和java基本上是相同的
注意用Environment.getExternalStorageDirectory()+"/"获得的SD目录最好
Java代码
package duohuo.teng.net;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.os.Environment;

public class FileUtil {

    private String SDPATH;

    public FileUtil() {
        //获得SD卡的路劲
        SDPATH=Environment.getExternalStorageDirectory()+"/";
    }


    /*创建文件
     *
     * */
    public File createFile(String fileName) throws IOException{
    File file=new File(SDPATH+fileName);
    file.createNewFile();
        return file;
    }
    /*创建文件夹
     *
     * */
    public File createDirs(String dirName){
        File file=new File(SDPATH+dirName);
        Boolean b=file.mkdirs();
        System.out.println(b);
        return file;
    }
    /*判断文件(夹)是否存在
     *
     * */
    public boolean isFileExist(String path){
        return new File(SDPATH+path).exists();

    }
    public File writeToSDFromInputStream(String path,String fileName,InputStream in){
        File file=null;
        OutputStream out = null;

        createDirs(path);
        try {
             path=path+"/"+fileName;
            System.out.println(path);
        file=createFile(path);
        out=new FileOutputStream(file);
        byte[] buffer=new byte[4*1024];
        while(in.read(buffer)!=-1){
            out.write(buffer);

        }

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            try {
                if(out!=null)
                out.close();
                if(in!=null)
                in.close();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }


        }


        return file;
    }
    /*delete file
     * @return 0 文件不存在 1删除成功
     * */
    public int deleteFile(String fileAllName){
        File file=new File(SDPATH+fileAllName);
    if(isFileExist(file.getPath())){
        return 0;
    }

    file.delete();
    return 1;






    }

}
下面是下载
Java代码
package duohuo.teng.net;

import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

public class HttpDownloadUtil {


    /*将文件保存为String
     * @param urlStr 本机测试是不是ip不是localhost和127.0.0.1,这是指android的IP,电脑是10.0.2.2
     * */
    public String downloadString(String urlStr){
        StringBuffer result=new StringBuffer();;
        URL url;
        InputStream in = null;
        BufferedReader reader=null;
        try {
             url=new URL(urlStr);
             HttpURLConnection con=(HttpURLConnection

补充：移动开发 , Android ,