可以实现文件下载的通用类：
我们没有测试过，只是摘录网站的内容。[code]import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import org.apache.http.Header;
import org.apache.http.HeaderElement;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
/**
- 说明
- 利用httpclient下载文件
- maven依赖
-
<groupId>org.apache.httpcomponents</groupId> -
<artifactId>httpclient</artifactId> -
<version>4.0.1</version> -
</dependency> - 可下载http文件、图片、压缩文件
- bug：获取response header中Content-Disposition中filename中文乱码问题
- @author tanjundong
*/
public class HttpDownload {
public static final int cache = 10 * 1024;
public static final boolean isWindows;
public static final String splash;
public static final String root;
static {
if (System.getProperty("os.name") != null && System.getProperty("os.name").toLowerCase().contains("windows")) {
isWindows = true;
splash = "\\";
root="D:";
} else {
isWindows = false;
splash = "/";
root="/search";
}
}
/**
* 根据url下载文件，文件名从response header头中获取
* @param url
* @return
*/
public static String download(String url) {
return download(url, null);
}
/**
* 根据url下载文件，保存到filepath中
* @param url
* @param filepath
* @return
*/
public static String download(String url, String filepath) {
try {
HttpClient client = new DefaultHttpClient();
HttpGet httpget = new HttpGet(url);
HttpResponse response = client.execute(httpget);
HttpEntity entity = response.getEntity();
InputStream is = entity.getContent();
if (filepath == null)
filepath = getFilePath(response);
File file = new File(filepath);
file.getParentFile().mkdirs();
FileOutputStream fileout = new FileOutputStream(file);
/**
* 根据实际运行效果 设置缓冲区大小
*/
byte[] buffer=new byte[cache];
int ch = 0;
while ((ch = is.read(buffer)) != -1) {
fileout.write(buffer,0,ch);
}
is.close();
fileout.flush();
fileout.close();
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 获取response要下载的文件的默认路径
* @param response
* @return
*/
public static String getFilePath(HttpResponse response) {
String filepath = root + splash;
String filename = getFileName(response);
if (filename != null) {
filepath += filename;
} else {
filepath += getRandomFileName();
}
return filepath;
}
/**
* 获取response header中Content-Disposition中的filename值
* @param response
* @return
*/
public static String getFileName(HttpResponse response) {
Header contentHeader = response.getFirstHeader("Content-Disposition");
String filename = null;
if (contentHeader != null) {
HeaderElement[] values = contentHeader.getElements();
if (values.length == 1) {
NameValuePair param = values[0].getParameterByName("filename");
if (param != null) {
try {
//filename = new String(param.getValue().toString().getBytes(), "utf-8");
//filename=URLDecoder.decode(param.getValue(),"utf-8");
filename = param.getValue();
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
return filename;
}
/**
* 获取随机文件名
* @return
*/
public static String getRandomFileName() {
return String.valueOf(System.currentTimeMillis());
}
public static void outHeaders(HttpResponse response) {
Header[] headers = response.getAllHeaders();
for (int i = 0; i < headers.length; i++) {
System.out.println(headers[i]);
}
}
public static void main(String[] args) {
// String url = “http://bbs.btwuji.com/job.php?action=download&pid=tpc&tid=320678&aid=216617”;
String url=“http://www.dy1000.com/img/20120701/1999311085_150_200.JPG”;
// String filepath = “D:\test\a.torrent”;
String filepath = “D:\test\a.jpg”;
HttpDownload.download(url, filepath);
}
}
[/code]
