本文整理匯總了Java中java.net.HttpURLConnection.setIfModifiedSince方法的典型用法代碼示例。如果您正苦於以下問題：Java HttpURLConnection.setIfModifiedSince方法的具體用法？Java HttpURLConnection.setIfModifiedSince怎麽用？Java HttpURLConnection.setIfModifiedSince使用的例子？那麽, 這裏精選的方法代碼示例或許可以為您提供幫助。您也可以進一步了解該方法所在類java.net.HttpURLConnection的用法示例。
在下文中一共展示了HttpURLConnection.setIfModifiedSince方法的2個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的Java代碼示例。
示例1: download
import java.net.HttpURLConnection; //導入方法依賴的package包/類
/**
* Check if there is a new version of the script engine
*
* @throws IOException
* if any error occur
*/
private void download() throws IOException {
boolean is32 = "32".equals( System.getProperty( "sun.arch.data.model" ) );
String fileName;
final String os = System.getProperty( "os.name", "" ).toLowerCase();
if( os.contains( "windows" ) ) {
fileName = is32 ? "win32" : "win64";
} else if( os.contains( "mac" ) ) {
fileName = is32 ? "mac" : "mac64";
} else if( os.contains( "linux" ) ) {
fileName = is32 ? "linux-i686" : "linux-x86_64";
} else {
throw new IllegalStateException( "Unknown OS: " + os );
}
File target = new File( System.getProperty( "java.io.tmpdir" ) + "/SpiderMonkey" );
URL url = new URL( "https://archive.mozilla.org/pub/firefox/nightly/latest-mozilla-central/jsshell-" + fileName
+ ".zip" );
System.out.println( "\tDownload: " + url );
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
if( target.exists() ) {
System.out.println( "\tUP-TP-DATE" );
conn.setIfModifiedSince( target.lastModified() );
}
InputStream input = conn.getInputStream();
command = target.getAbsolutePath() + "/js";
if( conn.getResponseCode() == HttpURLConnection.HTTP_NOT_MODIFIED ) {
return;
}
ZipInputStream zip = new ZipInputStream( input );
long lastModfied = conn.getLastModified();
do {
ZipEntry entry = zip.getNextEntry();
if( entry == null ) {
break;
}
if( entry.isDirectory() ) {
continue;
}
File file = new File( target, entry.getName() );
file.getParentFile().mkdirs();
Files.copy( zip, file.toPath(), StandardCopyOption.REPLACE_EXISTING );
file.setLastModified( entry.getTime() );
if( "js".equals( file.getName() ) ) {
file.setExecutable( true );
}
} while( true );
target.setLastModified( lastModfied );
}
示例2: updateManifestCacheFile
import java.net.HttpURLConnection; //導入方法依賴的package包/類
private boolean updateManifestCacheFile(String name, String localCache, String url, ServletContext context)
throws IOException
{
File downloadtmp = File.createTempFile(name, ".part");
File tmplocation = new File(_filesCacheDir);
if(!tmplocation.exists())
{ tmplocation.mkdir(); }
File cacheFile = new File(tmplocation, localCache);
long lastUpdatedCache = -1;
if(cacheFile.exists())
{
lastUpdatedCache = cacheFile.lastModified();
long twentyFourHoursAgo = System.currentTimeMillis() - (24L * 36000L);
if(lastUpdatedCache > twentyFourHoursAgo)
{
context.log("Skipping updating " + name + " catalog");
return false;
}
}
URL cacheURL = new URL(url);
HttpURLConnection cacheConnection = (HttpURLConnection) cacheURL.openConnection();
if(lastUpdatedCache > 0L)
{ cacheConnection.setIfModifiedSince(lastUpdatedCache); }
cacheConnection.connect();
switch(cacheConnection.getResponseCode())
{
case HttpURLConnection.HTTP_OK:
InputStream is = cacheConnection.getInputStream();
if("application/octet-stream".equals(cacheConnection.getContentType()))
{
ZipInputStream zis = new ZipInputStream(is);
zis.getNextEntry();
is = zis;
}
FileOutputStream os = new FileOutputStream(cacheFile, false);
byte[] buff = new byte[1024];
for(int br = is.read(buff); br > 0; br = is.read(buff))
{ os.write(buff, 0, br); }
os.close();
is.close();
context.log("manifest " + name + " updated");
break;
case HttpURLConnection.HTTP_NOT_MODIFIED:
context.log("manifest " + name + " not modified");
break;
default:
context.log("error updating " + name + ", got return code " + cacheConnection.getResponseCode() +" with message " + cacheConnection.getResponseMessage());
}
cacheConnection.disconnect();
return true;
}