android bt下载地址 http,Android文件下载使用Http协议

Android文件下载做法和JAVA的网络编程差不多，我没有使用第三方插件、方法。做的比较粗糙，高手绕道哈。

JAVA code

package cn.qiuzhping.study;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.net.HttpURLConnection;

import java.net.MalformedURLException;

import java.net.URL;

import android.app.Activity;

import android.os.Bundle;

import android.os.Environment;

import android.util.Log;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

public class DownloadStudy extends Activity {

private Button btn_download1 = null;

private Button btn_download2 = null;

/**

* @项目名称：study

* @类名称：HttpDownloder

* @作者：Qiuzhping

* @时间：2013-12-29下午11:04:11

* @作用 ：根据Http协议下载文件

*/

public class HttpDownloader {

private URL url = null;

/**

* @方法名: download

* @作者：Qiuzhping

* @作用: 根据网络路径 下载文本文件

* @返回值类型： String

*/

public String download(String urlStr) {

StringBuffer sb = new StringBuffer();

String line = null;

BufferedReader bufferReader = null;

try {

url = new URL(urlStr);

HttpURLConnection urlConn = (HttpURLConnection) url

.openConnection();

bufferReader = new BufferedReader(new InputStreamReader(

urlConn.getInputStream()));// BufferedReader

// 从字符输入流中读取文本，缓冲各个字符，从而实现字符、数组和行的高效读取

while ((line = bufferReader.readLine()) != null) {// 按行读取文本

sb.append(line);

}

} catch (Exception e) {

e.printStackTrace();

Log.w("download", "文本文件下载异常！！！");

} finally {

try {

if (bufferReader != null)

bufferReader.close();

} catch (IOException e) {

e.printStackTrace();

Log.w("download", "bufferReader关闭异常！！！");

}

}

return sb.toString();

}

/**

* @方法名: download

* @作者：Qiuzhping

* @作用: 下载非文本文件

* @返回值类型： int -1：下载失败 0: 下载成功 1：文件存在

*/

public int download(String urlStr, String parentName, String fileName) {

InputStream in = null;

FileUtil fileUtil = new FileUtil();

if (fileUtil.isFileExist(parentName + fileName))// 文件已经存在

return 1;

else {

in = getInputStreamFromUrl(urlStr);

File file = fileUtil.write2fromIn(parentName, fileName, in);

try {

if (in != null)

in.close();

} catch (IOException e) {

e.printStackTrace();

Log.i("download", "输入流in关闭异常！！！！");

}

if (file == null)

return -1;

}

return 0;

}

/**

* @方法名: getInputStreamFromUrl

* @作者：Qiuzhping

* @作用: 获取网络输入流

* @返回值类型： InputStream

*/

public InputStream getInputStreamFromUrl(String urlStr) {

InputStream in = null;

try {

url = new URL(urlStr);

HttpURLConnection urlConn = (HttpURLConnection) url

.openConnection();

in = urlConn.getInputStream();

} catch (MalformedURLException e) {

e.printStackTrace();

Log.w("getInputStreamFromUrl", "初始化url失败!!");

} catch (IOException e) {

e.printStackTrace();

Log.w("getInputStreamFromUrl", "openConnection失败!!");

}

return in;

}

}

/**

* @项目名称：study

* @类名称：FileUtil

* @作者：Qiuzhping

* @时间：2013-12-30上午10:57:12

* @作用 ：创建外部存储文件路径为/PATH/packageName/fileName

*/

public class FileUtil {

private final String cmd = "cat /proc/mounts";

private final String format = "sdcard";

private final String sdCard = Environment.getExternalStorageDirectory()

.getAbsolutePath();

private String PATH = null;

public String getExternlSD() {

File file = Environment.getExternalStorageDirectory();

File[] files = file.getParentFile().listFiles();

for (int i = 0; i < files.length; i++) {

Log.i("getExternlSD", files[i].getPath());

}

return null;

}

/**

* @方法名: getExternalPath

* @作者：Qiuzhping

* @作用: 获取真正的External sdcard路径

* @返回值类型： String

*/

public String getExternalPath() {

BufferedReader read = null;

String external_SDCard = sdCard;

Runtime runtime = Runtime.getRuntime();

try {

Process process = runtime.exec(cmd);

read = new BufferedReader(new InputStreamReader(

process.getInputStream()));

String line;

while ((line = read.readLine()) != null) {

if (line.toLowerCase().contains(format)) {

String[] array = line.split(" ");

if (array != null && array.length >= 5) {

String temp = array[1].replace("/.android_secure",

"");

if (!sdCard.equals(temp)) {

external_SDCard = temp;

}

}

}

}

} catch (Exception e) {

external_SDCard = sdCard;

e.printStackTrace();

}

return external_SDCard;

}

/**

* @方法名: getPath

* @作者：Qiuzhping

* @作用: 获取包名

* @返回值类型： String

*/

public String getPath() {

return PATH;

}

/**

* 默认是在SD卡上创建文件

*/

public FileUtil() {

/*

* if (Environment.getExternalStorageState().equals(

* Environment.MEDIA_MOUNTED)) { // 得到当前外部存储器的PATH 就是SDCard Path

* PATH = Environment.getExternalStorageState() + "/"

* +this.getClass().getPackage().getName() + "/"; }

*/

Log.i("FileUtil", this.getClass().getPackage().getName());

PATH = getExternalPath();

// PATH += this.getClass().getPackage().getName() + "/";

getExternlSD();

}

/**

* @方法名: createFile

* @作者：Qiuzhping

* @作用: 创建文件

* @返回值类型： File

*/

public File createFile(String parentName, String fileName) {

String packName = this.getClass().getName();

File dir = createDirFile(packName + "/" + parentName);

File file = new File(dir.getPath() + "/" + fileName);

try {

file.createNewFile();

} catch (IOException e) {

e.printStackTrace();

Log.w("createFile", file.getPath() + "创建异常！！！");

}

Log.w("createFile", file.getPath() + "创建成功!!!");

return file;

}

/**

* @方法名: createDirFile

* @作者：Qiuzhping

* @作用: 创建目录

* @返回值类型： File

*/

public File createDirFile(String dir) {

File dirFile = new File(PATH + "/" + dir);

dirFile.mkdirs();// 路径长使用mkdirs();

Log.i("createDirFile", dirFile.getPath() + "创建成功!!!");

return dirFile;

}

/**

* @方法名: isFileExist

* @作者：Qiuzhping

* @作用: 判断文件是否存在

* @返回值类型： boolean 如果由 filename 指定的文件或目录存在则返回 TRUE，否则返回 FALSE

*/

public boolean isFileExist(String fileName) {

File dirFile = new File(PATH + "/" + fileName);

return dirFile.exists();

}

/**

* @方法名: write2fromIuput

* @作者：Qiuzhping

* @作用: 根据提供的上一级目录parentName和fileName文件名字、二进制输入流in创建文件

* @返回值类型： File

*/

public File write2fromIn(String parentName, String fileName,

InputStream in) {

File file = null;

OutputStream out = null;

try {

file = createFile(parentName, fileName);// 创建文件

out = new FileOutputStream(file);

byte[] buffer = new byte[4 * 1024];// 每次缓存4个字节

while ((in.read(buffer)) != -1) {

out.write(buffer);

}

out.flush();// 刷新输出流

} catch (Exception e) {

e.printStackTrace();

Log.w("write2fromIuput", "文件创建异常！！");

} finally {

try {

if (out != null)

out.close();

} catch (IOException e) {

e.printStackTrace();

Log.w("write2fromIuput", "关闭输出流异常！！！");

}

}

return file;

}

}

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.download_study);

btn_download1 = (Button) findViewById(R.id.btn_download1);

btn_download1.setOnClickListener(new Btn_download1());

btn_download2 = (Button) findViewById(R.id.btn_download2);

btn_download2.setOnClickListener(new Btn_download2());

}

Runnable downloadRun = new Runnable() {//Android 4.0要使用线程访问网络，否则将会出现警告

@Override

public void run() {

HttpDownloader downloader = new HttpDownloader();

Log.i("Btn_download1",

downloader.download("http://10.0.0.91:8080/ems/down.txt"));

Log.i("Btn_download1",

"状态 = "

+ downloader

.download(

"http://10.0.0.91:8080/ems/antlr-2.7.6.jar",

"jsp", "antlr-2.7.6.jar"));

}

};

class Btn_download1 implements OnClickListener {

@Override

public void onClick(View arg0) {

new Thread(downloadRun).start();

}

}

class Btn_download2 implements OnClickListener {

@Override

public void onClick(View arg0) {

new Thread(downloadRun).start();

// HttpDownloader downloader = new HttpDownloader();

// Log.i("Btn_download1",

// "状态 = "

// + downloader.download(

// "http://10.0.0.91:8080/ems/index.jsp",

// "jsp", "index.jsp"));

}

}

}

xml

xmlns:tools="http://schemas.android.com/tools"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:paddingBottom="@dimen/activity_vertical_margin"

android:paddingLeft="@dimen/activity_horizontal_margin"

android:paddingRight="@dimen/activity_horizontal_margin"

android:paddingTop="@dimen/activity_vertical_margin"

tools:context=".SQLiteStudy" >

android:id="@+id/btn_download1"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:text="下载文本" />

android:id="@+id/btn_download2"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_below="@+id/btn_download1"

android:text="下载其他" />