java 重定向下载_Java 获取网络302重定向URL的方法
方法1：
import java.net.HttpURLConnection;
import java.net.URL;
import org.junit.Assert;
import org.junit.Test;
public class GetRedirectUrlTest {
@Test
public void test_getRedirectUrl() throws Exception {
在Java编程中，请注意以下内容：url字段被初始化为http://www.baidu.com/link，并链接至$ByBJLpHsj5nXx6DESXbmMjIrU5W4Eh0yg5wCQpe3kCQMlJK_RJBmdEYGm0DDTCoTDGaz7rH80gxjvtvoqJuYxK
String expectUrl="http://www.zhihu.com/question/20583607/answer/16597802";
String redictURL = getRedirectUrl(url);
Assert.assertEquals(expectUrl, redictURL);
}
/**
-
获取重定向地址
-
@param path
-
@return
-
@throws Exception
*/
private String getRedirectUrl(String path) throws Exception {
HttpURLConnection conn = (HttpURLConnection) new URL(path)
.openConnection();
conn.setInstanceFollowRedirects(false);
conn.setConnectTimeout(5000);
return conn.getHeaderField("Location");
}
}
方法2：
/**
-
处理跳转链接，获取重定向地址
-
@param url 源地址
-
@return 目标网页的绝对地址
*/
public String getAbsUrl(String url){
CloseableHttpClient httpclient = HttpClients.createDefault();
HttpClientContext context = HttpClientContext.create();
HttpGet httpget = new HttpGet(url);
CloseableHttpResponse response = null;
String absUrl = null;
try {
response = httpclient.execute(httpget, context);
HttpHost target = context.getTargetHost();
List redirectLocations = context.getRedirectLocations();
Uniform Resource Identifier（URI） location = URIUtils.resolve(httpGet.requestUri(target), target, redirectLocations);
System.out.println("Final HTTP location: " + location.toASCIIString());
absUrl = location.toASCIIString();
}catch(IOException e){
e.printStackTrace();
}catch (URISyntaxException e) {
e.printStackTrace();
}finally {
try {
httpclient.close();
response.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return absUrl;
}
以上就是2中最常用的方法，感谢大家对谷谷点程序的支持。