org.owasp.dependencycheck.utils

Class Downloader

java.lang.Object

org.owasp.dependencycheck.utils.Downloader

public final class Downloader
extends Object

A utility to download files from the Internet.

Author:

Jeremy Long

Method Summary

Modifier and Type	Method and Description
protected static void	checkForCommonExceptionTypes(IOException ex) Analyzes the IOException, logs the appropriate information for debugging purposes, and then throws a DownloadFailedException that wraps the IO Exception for common IO Exceptions.
static void	fetchFile(URL url, File outputPath) Retrieves a file from a given URL and saves it to the outputPath.
static void	fetchFile(URL url, File outputPath, boolean useProxy) Retrieves a file from a given URL and saves it to the outputPath.
static long	getLastModified(URL url) Makes an HTTP Head request to retrieve the last modified date of the given URL.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

fetchFile

public static void fetchFile(URL url,
                             File outputPath)
                      throws DownloadFailedException

Retrieves a file from a given URL and saves it to the outputPath.

Parameters:

url - the URL of the file to download

outputPath - the path to the save the file to

Throws:

DownloadFailedException - is thrown if there is an error downloading the file

fetchFile

public static void fetchFile(URL url,
                             File outputPath,
                             boolean useProxy)
                      throws DownloadFailedException

Retrieves a file from a given URL and saves it to the outputPath.

Parameters:

url - the URL of the file to download

outputPath - the path to the save the file to

useProxy - whether to use the configured proxy when downloading files

Throws:

DownloadFailedException - is thrown if there is an error downloading the file

getLastModified

public static long getLastModified(URL url)
                            throws DownloadFailedException

Makes an HTTP Head request to retrieve the last modified date of the given URL. If the file:// protocol is specified, then the lastTimestamp of the file is returned.

Parameters:

url - the URL to retrieve the timestamp from

Returns:

an epoch timestamp

Throws:

DownloadFailedException - is thrown if an exception occurs making the HTTP request

checkForCommonExceptionTypes

protected static void checkForCommonExceptionTypes(IOException ex)
                                            throws DownloadFailedException

Analyzes the IOException, logs the appropriate information for debugging purposes, and then throws a DownloadFailedException that wraps the IO Exception for common IO Exceptions. This is to provide additional details to assist in resolution of the exception.

Parameters:

ex - the original exception

Throws:

DownloadFailedException - a wrapper exception that contains the original exception as the cause