gov.lanl.archive.rewrite
Class UrlOperations

java.lang.Object
  gov.lanl.archive.rewrite.UrlOperations

public class UrlOperations
extends Object

Class containing common static URL methods. Primarily resolveUrl() and the (currently) unused isAuthority().

Version:

$Date: 2011-05-24 19:08:38 -0600 (Tue, 24 May 2011) $, $Revision: 3442 $

Author:

brad

Field Summary

static String[]	ALL_SCHEMES array of static Strings for all "known" schemes
static String	DEFAULT_SCHEME Default scheme to assume if unspecified.
static String	DNS_SCHEME ARC/WARC specific DNS resolution record.
static String	FTP_SCHEME FTP
static String	HTTP_SCHEME HTTP
static String	HTTPS_SCHEME HTTPS
static String	MMS_SCHEME MMS
static char	PATH_START character which delimits the path from the authority in a...
static char	PORT_SEPARATOR character separating host from port within a URL authority
static String	RTSP_SCHEME RTSP
static String	WAIS_SCHEME go brewster

Constructor Summary

UrlOperations()

Method Summary

static String	fixupHTTPUrlWithOneSlash(String orig)
static String	getUrlParentDir(String url) Find and return the parent directory of the URL argument
static String	getURLPath(String url) Attempt to extract the path component of a url String argument.
static boolean	isAuthority(String authString) Tests if the String argument looks like it could be a legitimate authority fragment of a URL, that is, is it an IP address, or, are the characters legal in an authority, and does the string end with a legal TLD.
static String	resolveUrl(String baseUrl, String url) Resolve a possibly relative url argument against a base URL.
static int	schemeToDefaultPort(String scheme) Return the default port for the scheme String argument, if known.
static String	stripDefaultPortFromUrl(String url) Attempt to strip default ports out of URL strings.
static String	stripURLScheme(String url) Attempt to extract the path component of a url String argument.
static String	urlToHost(String url) Attempt to extract the hostname component of an absolute URL argument.
static String	urlToScheme(String url) Attempt to find the scheme (http://, https://, etc) from a given URL.
static String	urlToUserInfo(String url) Extract userinfo from the absolute URL argument, that is, "username@", or "username:password@" if present.

Methods inherited from class java.lang.Object

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

Field Detail

DNS_SCHEME

public static final String DNS_SCHEME

ARC/WARC specific DNS resolution record.

See Also:

Constant Field Values

HTTP_SCHEME

public static final String HTTP_SCHEME

HTTP

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Constant Field Values

HTTPS_SCHEME

public static final String HTTPS_SCHEME

HTTPS

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Constant Field Values

FTP_SCHEME

public static final String FTP_SCHEME

FTP

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Constant Field Values

MMS_SCHEME

public static final String MMS_SCHEME

MMS

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Constant Field Values

RTSP_SCHEME

public static final String RTSP_SCHEME

RTSP

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Constant Field Values

DEFAULT_SCHEME

public static final String DEFAULT_SCHEME

Default scheme to assume if unspecified. No context implied...

See Also:

Constant Field Values

WAIS_SCHEME

public static final String WAIS_SCHEME

go brewster

See Also:

Constant Field Values

ALL_SCHEMES

public static final String[] ALL_SCHEMES

array of static Strings for all "known" schemes

PORT_SEPARATOR

public static final char PORT_SEPARATOR

character separating host from port within a URL authority

See Also:

Constant Field Values

PATH_START

public static final char PATH_START

character which delimits the path from the authority in a... in some URLs.

See Also:

Constant Field Values

Constructor Detail

UrlOperations

public UrlOperations()

Method Detail

isAuthority

public static boolean isAuthority(String authString)

Tests if the String argument looks like it could be a legitimate authority fragment of a URL, that is, is it an IP address, or, are the characters legal in an authority, and does the string end with a legal TLD.

Parameters:

authString - String representation of a fragment of a URL

Returns:

boolean indicating whether urlPart might be an Authority.

resolveUrl

public static String resolveUrl(String baseUrl,
                                String url)

Resolve a possibly relative url argument against a base URL.

Parameters:

baseUrl - the base URL against which the url should be resolved

url - the URL, possibly relative, to make absolute.

Returns:

url resolved against baseUrl, unless it is absolute already, and further transformed by whatever escaping normally takes place with a UURI.

urlToScheme

public static String urlToScheme(String url)

Attempt to find the scheme (http://, https://, etc) from a given URL.

Parameters:

url - URL String to parse for a scheme.

Returns:

the scheme, including trailing "://" if known, null otherwise.

schemeToDefaultPort

public static int schemeToDefaultPort(String scheme)

Return the default port for the scheme String argument, if known.

Parameters:

scheme - String scheme, including '://', as in, "http://", "ftp://"

Returns:

the default port for the scheme, or -1 if the scheme isn't known.

getURLPath

public static String getURLPath(String url)

Attempt to extract the path component of a url String argument.

Parameters:

url - the URL which may contain a path, sans scheme.

Returns:

the path component of the URL, or "" if it contains no path.

stripURLScheme

public static String stripURLScheme(String url)

Attempt to extract the path component of a url String argument.

Parameters:

url - the URL which may contain a path, sans scheme.

Returns:

the path component of the URL, or "" if it contains no path.

stripDefaultPortFromUrl

public static String stripDefaultPortFromUrl(String url)

Attempt to strip default ports out of URL strings.

Parameters:

url - the original URL possibly including a port

Returns:

the URL sans port, if the scheme was recognized and the default port was supplied, otherwise, the original URL.

fixupHTTPUrlWithOneSlash

public static String fixupHTTPUrlWithOneSlash(String orig)

Parameters:

orig - String containing a URL, possibly beginning with "http:/".

Returns:

original string if orig begins with "http://", or a new String with the extra slash, if orig only had one slash.

urlToHost

public static String urlToHost(String url)

Attempt to extract the hostname component of an absolute URL argument.

Parameters:

url - the url String from which to extract the hostname

Returns:

the hostname within the URL, or the url argument if the host cannot be found.

urlToUserInfo

public static String urlToUserInfo(String url)

Extract userinfo from the absolute URL argument, that is, "username@", or "username:password@" if present.

Parameters:

url - the URL from which to extract the userinfo

Returns:

the userinfo found, not including the "@", or null if no userinfo is found

getUrlParentDir

public static String getUrlParentDir(String url)

Find and return the parent directory of the URL argument

Parameters:

url - to find the parent directory of

Returns:

parent directory of URL, or null, if either the url argument is invalid, or if the url is the root of the authority.