picsou.util
Class UrlValidator

java.lang.Object
  picsou.util.UrlValidator

All Implemented Interfaces:

java.io.Serializable

public class UrlValidator
extends java.lang.Object
implements java.io.Serializable

Validates URLs.

Behavour of validation is modified by passing in options:

ALLOW_2_SLASHES - [FALSE] Allows double '/' characters in the path component.

NO_FRAGMENT- [FALSE] By default fragments are allowed, if this option is included then fragments are flagged as illegal.

ALLOW_ALL_SCHEMES - [FALSE] By default only http, https, and ftp are considered valid schemes. Enabling this option will let any scheme pass validation.

Originally based in on php script by Debbie Dyer, validation.php v1.2b, Date: 03/07/02, http://javascript.internet.com. However, this validation now bears little resemblance to the php original.

   Example of usage:
   Construct a UrlValidator with valid schemes of "http", and "https".

    String[] schemes = {"http","https"}.
    UrlValidator urlValidator = new UrlValidator(schemes);
    if (urlValidator.isValid("ftp://foo.bar.com/")) {
       System.out.println("url is valid");
    } else {
       System.out.println("url is invalid");
    }

    prints "url is invalid"
   If instead the default constructor is used.

    UrlValidator urlValidator = new UrlValidator();
    if (urlValidator.isValid("ftp://foo.bar.com/")) {
       System.out.println("url is valid");
    } else {
       System.out.println("url is invalid");
    }

   prints out "url is valid"
  

Since:

Validator 1.1

See Also:

Uniform Resource Identifiers (URI): Generic Syntax , Serialized Form

Field Summary

static int	ALLOW_2_SLASHES Allow two slashes in the path component of the URL.
static int	ALLOW_ALL_SCHEMES Allows all validly formatted schemes to pass validation instead of supplying a set of valid schemes.
protected java.lang.String[]	defaultSchemes If no schemes are provided, default to this set.
static int	NO_FRAGMENTS Enabling this options disallows any URL fragments.

Constructor Summary

UrlValidator()
Create a UrlValidator with default properties.

UrlValidator(int options)
Initialize a UrlValidator with the given validation options.

UrlValidator(java.lang.String[] schemes)
Behavior of validation is modified by passing in several strings options:

UrlValidator(java.lang.String[] schemes, int options)
Behavour of validation is modified by passing in options:

Method Summary

protected int	countToken(java.lang.String token, java.lang.String target) Returns the number of times the token appears in the target.
boolean	isValid(java.lang.String value) Checks if a field has a valid url address.
protected boolean	isValidAuthority(java.lang.String authority) Returns true if the authority is properly formatted.
protected boolean	isValidFragment(java.lang.String fragment) Returns true if the given fragment is null or fragments are allowed.
protected boolean	isValidPath(java.lang.String path) Returns true if the path is valid.
protected boolean	isValidQuery(java.lang.String query) Returns true if the query is null or it's a properly formatted query string.
protected boolean	isValidScheme(java.lang.String scheme) Validate scheme.

Methods inherited from class java.lang.Object

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

Field Detail

ALLOW_ALL_SCHEMES

public static final int ALLOW_ALL_SCHEMES

Allows all validly formatted schemes to pass validation instead of supplying a set of valid schemes.

See Also:

Constant Field Values

ALLOW_2_SLASHES

public static final int ALLOW_2_SLASHES

Allow two slashes in the path component of the URL.

See Also:

Constant Field Values

NO_FRAGMENTS

public static final int NO_FRAGMENTS

Enabling this options disallows any URL fragments.

See Also:

Constant Field Values

defaultSchemes

protected java.lang.String[] defaultSchemes

If no schemes are provided, default to this set.

Constructor Detail

UrlValidator

public UrlValidator()

Create a UrlValidator with default properties.

UrlValidator

public UrlValidator(java.lang.String[] schemes)

Behavior of validation is modified by passing in several strings options:

Parameters:

schemes - Pass in one or more url schemes to consider valid, passing in a null will default to "http,https,ftp" being valid. If a non-null schemes is specified then all valid schemes must be specified. Setting the ALLOW_ALL_SCHEMES option will ignore the contents of schemes.

UrlValidator

public UrlValidator(int options)

Initialize a UrlValidator with the given validation options.

Parameters:

options - The options should be set using the public constants declared in this class. To set multiple options you simply add them together. For example, ALLOW_2_SLASHES + NO_FRAGMENTS enables both of those options.

UrlValidator

public UrlValidator(java.lang.String[] schemes,
                    int options)

Behavour of validation is modified by passing in options:

Parameters:

schemes - The set of valid schemes.

options - The options should be set using the public constants declared in this class. To set multiple options you simply add them together. For example, ALLOW_2_SLASHES + NO_FRAGMENTS enables both of those options.

Method Detail

isValid

public boolean isValid(java.lang.String value)

Checks if a field has a valid url address.

Parameters:

value - The value validation is being performed on. A null value is considered invalid.

Returns:

true if the url is valid.

isValidScheme

protected boolean isValidScheme(java.lang.String scheme)

Validate scheme. If schemes[] was initialized to a non null, then only those scheme's are allowed. Note this is slightly different than for the constructor.

Parameters:

scheme - The scheme to validate. A null value is considered invalid.

Returns:

true if valid.

isValidAuthority

protected boolean isValidAuthority(java.lang.String authority)

Returns true if the authority is properly formatted. An authority is the combination of hostname and port. A null authority value is considered invalid.

Parameters:

authority - Authority value to validate.

Returns:

true if authority (hostname and port) is valid.

isValidPath

protected boolean isValidPath(java.lang.String path)

Returns true if the path is valid. A null value is considered invalid.

Parameters:

path - Path value to validate.

Returns:

true if path is valid.

isValidQuery

protected boolean isValidQuery(java.lang.String query)

Returns true if the query is null or it's a properly formatted query string.

Parameters:

query - Query value to validate.

Returns:

true if query is valid.

isValidFragment

protected boolean isValidFragment(java.lang.String fragment)

Returns true if the given fragment is null or fragments are allowed.

Parameters:

fragment - Fragment value to validate.

Returns:

true if fragment is valid.

countToken

protected int countToken(java.lang.String token,
                         java.lang.String target)

Returns the number of times the token appears in the target.

Parameters:

token - Token value to be counted.

target - Target value to count tokens in.

Returns:

the number of tokens.