使用Java下载的PDF已损坏？ [英] Downloaded PDF with Java is corrupt?
本文介绍了使用Java下载的PDF已损坏？的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我已阅读关于的卓越讨论如何使用Java从互联网下载和保存文件。但是，如果我浏览下一个代码，我得到一个损坏的PDF。任何想法为什么？
import java.io. *;
import java.net。*;
public class PDFDownload {
public static String URL =http://www.nbc.com/Heroes/novels/downloads/;
public static String FOLDER =C：/ Users / sdelamo / workspace / SandBox / HeroesNovel /;
public static void main（String [] args）{
String filename =Heroes_novel_001.pdf;
尝试{
saveUrl（FOLDER + filename，URL + filename）;
} catch（MalformedURLException e）{
System.out.println（MalformedURLException）;
} catch（IOException e）{
System.out.println（IOException）;
}
}
public static void saveUrl（String filename，String urlString）throws MalformedURLException，IOException {
BufferedInputStream in = null ;
FileOutputStream fout = null;
try {
URL url = new URL（urlString）;
in = new BufferedInputStream（url.openStream（））;
fout = new FileOutputStream（filename）;
字节数据[] =新字节[1024];
int count;
while（（count = in.read（data，0，1024））！= -1）{
fout.write（data，0，count）;
}
} finally {
if（in！= null）
in.close（）;
if（fout！= null）
fout.close（）;
}
}
}
以上代码下载html的PDF。这是输出：
<？xml version =1.0encoding =UTF-8？>
<！DOCTYPE html PUBLIC - // W3C // DTD XHTML Basic 1.1 // EN
http://www.w3.org/TR/xhtml-basic/xhtml-basic11。 DTD>
< html xmlns =http://www.w3.org/1999/xhtmlxml：lang =enlang =en>
< head>
< meta name =viewportcontent =width = 240，user-scalable = yes/>
< HTTP-EQUIV =PRAGMACONTENT =NO-CACHE>
< META HTTP-EQUIV =ExpiresCONTENT = - 1>
< meta http-equiv =Cache-controlcontent =no-cache>
< meta http-equiv =Cache-controlcontent =must-revalidate>
< meta http-equiv =Cache-controlcontent =max-age = 0>
< meta http-equiv =refreshcontent =200>
< title> NBC.com：Heroes< / title>
< link rel =stylesheettype =text / csshref =/ style / default.css？sid = 8a9212f822e1c675330ec418bc531169/>
< link rel =stylesheettype =text / csshref =/ style / hro.css？sid = 8a9212f822e1c675330ec418bc531169/>
< / head>
< body>
< center>< img src =http://oimg.nbcuni.com/b/ss/nbcunbcnetworkwapbu,nbcuwapsitebu/5/H.8--WAP/4aa0e4cb8b448?vid=8a9212f822e1c675330ec418bc531169&gn=NBC .com前门& c2 =& c3 =杂项& c6 =& c6 = m.nbc.com / show / hro& c8 =电视娱乐& c9 = NBC网络& c10 =& c11 = |& c12 = |& c25 = offdeck& c27 = internal& c29 =& c44 = D = User-Agent& r =width =5height =5border =0/>< / center&
< h1 id =fHeader>
< a href =/？sid = 8a9212f822e1c675330ec418bc531169>
< img src =/ images / nbc_logo.gifalt =NBC：logoborder =0/>
< / a>
< / h1>
< h2>
< a href =/ show / hro？sid = 8a9212f822e1c675330ec418bc531169>
< img src =/ images / shows / 1221684699_Heroes_WAP_166x54.jpgalt =Heroes：showheaderborder =0/>
< / a>
< / h2>
< div id =tunein_nexton>
< span id =tunein>星期一9 / 8c< / span>
< / div><！ - end #tunein_nexton - >
< div id =tunein_nexton>
<！ - < span id =tunein>星期一8 / 7c< / span> - >
< p id =nexton>< span class =sectiontitle>< / span>< / p>
< / div><！ - end #tunein_nexton - >
< div id =featuredcontent>
< h3>特征内容< / h3>
< table id =featuredItemsTable>
< tr>
< td>< a href =/ show / hro / videos.html？sid = 8a9212f822e1c675330ec418bc531169>< img src =/ images / hro / nbc_hro_pro_040X921HRO120FLYPSIDE_exp921_20090_543_large.jpgalt = >< / A>
< / td>
< td>
< span class =ftitle> Dreams< / span>
< span class =fdesc>英雄首映式星期一，9月21日...< / span>
< / td>
< / tr>
< tr>
< td>< a href =/ show / hro / recaps.html？sid = 8a9212f822e1c675330ec418bc531169>< img src =http://origin-www.nbc.com/Heroes/images /episodes/season3/325/hro_325_01.jpgalt =featureheight =45width =80/>< / a>
< / td>
< td>
< span class =ftitle> Recap：< / span>
< span class =fdesc>第3季剧集不可见的线程< / span>
< / td>
< / tr>
< tr>
< td>< a href =/ show / hro / photos.html？sid = 8a9212f822e1c675330ec418bc531169>< img src =http://origin-www.nbc.com/app2/img /200x200xS/scet/photos/51/3736/NUP_110031_0323.JPGalt =featuresheight =45width =80/>< / a>
< / td>
< td class =finfo>
< span class =ftitle>照片：< / span>
< span class =fdesc> HeroesCast Photos< / span>
< / td>
< / tr>
< / table>
< / div><！ - end #featuredcontent - >
< h3> HEROES< / h3>
< table class =showNav>
< tr>< td>< a href =/ show / hro / about.html？sid = 8a9212f822e1c675330ec418bc531169accesskey =1>关于< / a>< / td& / TR>
< tr>< td>< a href =/ show / hro /Videos.html？sid = 8a9212f822e1c675330ec418bc531169accesskey =2>视频< / a>< / td& / TR>
< tr>< td>< a href =/ show / hro / recaps.html？sid = 8a9212f822e1c675330ec418bc531169accesskey =3>剧集回顾< / a>< / td>< ; / TR>
< tr>< td>< a href =/ show / hro / photos.html？sid = 8a9212f822e1c675330ec418bc531169accesskey =4>照片< / a>< / td& / TR>
< tr>< td>< a href =/ show / hro / community.html？sid = 8a9212f822e1c675330ec418bc531169accesskey =5> Community< / a>< / td& / TR>
< tr>< td>< a href =/ shows.shtml？sid = 8a9212f822e1c675330ec418bc531169accesskey =6>显示列表< / a>< / td>< / tr>
< / table>
<！ - < a href =http://www.insightexpress.com/ix/Survey.aspx?id=151580&accessCode=3161643404&sid=8a9212f822e1c675330ec418bc531169>< img src = /images/mNBCcom_166x54.jpgborder =0>< / a> - >
< div class =footeralign =center>< a href =http://m.nbc.com?sid=8a9212f822e1c675330ec418bc531169 < strong> NBC Mobile Main< / strong>< / a> | < a href =/ terms.shtml？sid = 8a9212f822e1c675330ec418bc531169>< strong>使用条款< / strong>< / a> | < a href =/ privacy.shtml？sid = 8a9212f822e1c675330ec418bc531169>< strong>隐私< / strong>< / a>< / div>< div class =cpyrtalign =center> ;&安培;＃169; NBC Universal，Inc.< / div>
< / body>
< / html>
任何想法如何下载PDF？
解决方案
在连接之前设置用户代理。
URL u = new URL（urlString）;
HttpURLConnection huc =（HttpURLConnection）u.openConnection（）;
huc.setRequestMethod（GET）;
huc.setRequestProperty（User-Agent，Mozilla / 5.0（Windows; U; Windows NT 6.0; en-US; rv：1.9.1.2）Gecko / 20090729 Firefox / 3.5.2（.NET CLR 3.5 0.30729））;
huc.connect（）;
in = new BufferedInputStream（huc.getInputStream（））;
解决方案
与您的其他问题同样的问题。如果NBC.com认为您是刮刀，NBC.com不会将PDF发送给您：）
相同的技巧将会执行，
pre>
conn.setRequestProperty（User-Agent，Mozilla / 5.0（Macintosh; U; Intel Mac OS X 10.5; en-US; rv：1.9.0.13）Gecko / 2009073021 Firefox / 3.0.13）;
I have read the excelent discussion about How to download and save a file from internet using Java. However, if I exectue the next code, i get a corrupt PDF. Any idea why?
import java.io.*;
import java.net.*;
public class PDFDownload {
public static String URL = "http://www.nbc.com/Heroes/novels/downloads/";
public static String FOLDER = "C:/Users/sdelamo/workspace/SandBox/HeroesNovel/";
public static void main(String[] args) {
String filename = "Heroes_novel_001.pdf";
try {
saveUrl(FOLDER + filename, URL + filename);
} catch (MalformedURLException e) {
System.out.println("MalformedURLException");
} catch (IOException e) {
System.out.println("IOException");
}
}
public static void saveUrl(String filename, String urlString) throws MalformedURLException, IOException {
BufferedInputStream in = null;
FileOutputStream fout = null;
try {
URL url = new URL(urlString);
in = new BufferedInputStream(url.openStream());
fout = new FileOutputStream(filename);
byte data[] = new byte[1024];
int count;
while ((count = in.read(data, 0, 1024)) != -1) {
fout.write(data, 0, count);
}
} finally {
if (in != null)
in.close();
if (fout != null)
fout.close();
}
}
}
The above code downloads html instead of a PDF. This is the output:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.1//EN"
"http://www.w3.org/TR/xhtml-basic/xhtml-basic11.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta name="viewport" content="width=240, user-scalable=yes" />
<HTTP-EQUIV="PRAGMA" CONTENT="NO-CACHE">
<META HTTP-EQUIV="Expires" CONTENT="-1">
<meta http-equiv="Cache-control" content="no-cache">
<meta http-equiv="Cache-control" content="must-revalidate">
<meta http-equiv="Cache-control" content="max-age=0">
<meta http-equiv="refresh" content="200">
<title>NBC.com: Heroes</title>
<link rel="stylesheet" type="text/css" href="/style/default.css?sid=8a9212f822e1c675330ec418bc531169" />
<link rel="stylesheet" type="text/css" href="/style/hro.css?sid=8a9212f822e1c675330ec418bc531169" />
</head>
<body>
<center><img src="http://oimg.nbcuni.com/b/ss/nbcunbcnetworkwapbu,nbcuwapsitebu/5/H.8--WAP/4aa0e4cb8b448?vid=8a9212f822e1c675330ec418bc531169&gn=NBC.com Front Door&c2=&c3=Miscellaneous&c4=&c6=m.nbc.com/show/hro&c8=TV Entertainment&c9=NBC Network&c10=&c11= | &c12= | &c25=offdeck&c27=internal&c29=&c44=D=User-Agent&r=" width="5" height="5" border="0" /></center>
<h1 id="fHeader">
<a href="/?sid=8a9212f822e1c675330ec418bc531169">
<img src="/images/nbc_logo.gif" alt="NBC : logo" border="0" />
</a>
</h1>
<h2>
<a href="/show/hro?sid=8a9212f822e1c675330ec418bc531169">
<img src="/images/shows/1221684699_Heroes_WAP_166x54.jpg" alt="Heroes : showheader" border="0" />
</a>
</h2>
<div id="tunein_nexton">
<span id="tunein">Mondays 9/8c</span>
</div><!--end #tunein_nexton-->
<div id="tunein_nexton">
<!--<span id="tunein">Mondays 8/7c</span>-->
<p id="nexton"><span class="sectiontitle"></span></p>
</div><!--end #tunein_nexton-->
<div id="featuredcontent">
<h3>FEATURED CONTENT</h3>
<table id="featuredItemsTable">
<tr>
<td><a href="/show/hro/videos.html?sid=8a9212f822e1c675330ec418bc531169"><img src="/images/hro/nbc_hro_pro_040X921HRO120FLYPSIDE_exp921_20090_543_large.jpg" alt="featured" /></a>
</td>
<td>
<span class="ftitle">Dreams</span>
<span class="fdesc">Heroes premieres Mon., Sept. 21s...</span>
</td>
</tr>
<tr>
<td><a href="/show/hro/recaps.html?sid=8a9212f822e1c675330ec418bc531169"><img src="http://origin-www.nbc.com/Heroes/images/episodes/season3/325/hro_325_01.jpg" alt="featured" height="45" width="80"/></a>
</td>
<td>
<span class="ftitle">Recap:</span>
<span class="fdesc">Season 3 Episode An Invisible Thread</span>
</td>
</tr>
<tr>
<td><a href="/show/hro/photos.html?sid=8a9212f822e1c675330ec418bc531169"><img src="http://origin-www.nbc.com/app2/img/200x200xS/scet/photos/51/3736/NUP_110031_0323.JPG" alt="featured" height="45" width="80"/></a>
</td>
<td class="finfo">
<span class="ftitle">Photo:</span>
<span class="fdesc">Heroes "Cast Photos"</span>
</td>
</tr>
</table>
</div><!--end #featuredcontent-->
<h3>HEROES</h3>
<table class="showNav">
<tr><td><a href="/show/hro/about.html?sid=8a9212f822e1c675330ec418bc531169" accesskey="1">About</a></td></tr>
<tr><td><a href="/show/hro/videos.html?sid=8a9212f822e1c675330ec418bc531169" accesskey="2">Videos</a></td></tr>
<tr><td><a href="/show/hro/recaps.html?sid=8a9212f822e1c675330ec418bc531169" accesskey="3">Episode Recaps</a></td></tr>
<tr><td><a href="/show/hro/photos.html?sid=8a9212f822e1c675330ec418bc531169" accesskey="4">Photos</a></td></tr>
<tr><td><a href="/show/hro/community.html?sid=8a9212f822e1c675330ec418bc531169" accesskey="5">Community</a></td></tr>
<tr><td><a href="/shows.shtml?sid=8a9212f822e1c675330ec418bc531169" accesskey="6">Shows List</a></td></tr>
</table>
<!-- <a href="http://www.insightexpress.com/ix/Survey.aspx?id=151580&accessCode=3161643404&sid=8a9212f822e1c675330ec418bc531169" ><img src="/images/mNBCcom_166x54.jpg" border="0"></a> -->
<div class="footer" align="center"><a href="http://m.nbc.com?sid=8a9212f822e1c675330ec418bc531169"><strong>NBC Mobile Main</strong></a> | <a href="/terms.shtml?sid=8a9212f822e1c675330ec418bc531169"><strong>Terms of Use</strong></a> | <a href="/privacy.shtml?sid=8a9212f822e1c675330ec418bc531169"><strong>Privacy</strong></a></div><div class="cpyrt" align="center">© NBC Universal, Inc.</div>
</body>
</html>
Any idea how to download the PDF?
SOLUTION
Set User-Agent before connecting.
URL u = new URL(urlString);
HttpURLConnection huc = (HttpURLConnection) u.openConnection();
huc.setRequestMethod("GET");
huc.setRequestProperty("User-Agent", " Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.1.2) Gecko/20090729 Firefox/3.5.2 (.NET CLR 3.5.30729)");
huc.connect();
in = new BufferedInputStream(huc.getInputStream());
解决方案
This is the same issue with your other question. NBC.com doesn't send back PDF to you if it thinks you are a scraper :)
Same tricks will do,
conn.setRequestProperty("User-Agent", "Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.5; en-US; rv:1.9.0.13) Gecko/2009073021 Firefox/3.0.13");
这篇关于使用Java下载的PDF已损坏？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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