Class UrlValidator

  • All Implemented Interfaces:
    java.io.Serializable

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

    URL Validation routines.

    Behavior 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, https://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:
    1.4
    See Also:
    Uniform Resource Identifiers (URI): Generic Syntax , Serialized Form
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static long ALLOW_2_SLASHES
      Allow two slashes in the path component of the URL.
      static long ALLOW_ALL_SCHEMES
      Allows all validly formatted schemes to pass validation instead of supplying a set of valid schemes.
      static long ALLOW_LOCAL_URLS
      Allow local URLs, such as https://localhost/ or https://machine/ .
      static long NO_FRAGMENTS
      Enabling this options disallows any URL fragments.
    • Constructor Summary

      Constructors 
      Constructor Description
      UrlValidator()
      Constructs a new instance with default properties.
      UrlValidator​(long options)
      Constructs a new instance 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, long options)
      Behavior of validation is modified by passing in options:
      UrlValidator​(java.lang.String[] schemes, RegexValidator authorityValidator, long options)
      Customizable constructor.
      UrlValidator​(java.lang.String[] schemes, RegexValidator authorityValidator, long options, DomainValidator domainValidator)
      Customizable constructor.
      UrlValidator​(RegexValidator authorityValidator, long options)
      Constructs a new instance with the given validation options.
    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      protected int countToken​(java.lang.String token, java.lang.String target)
      Returns the number of times the token appears in the target.
      static UrlValidator getInstance()
      Returns the singleton instance of this class with default schemes and options.
      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
    • Constructor Detail

      • UrlValidator

        public UrlValidator()
        Constructs a new instance with default properties.
      • UrlValidator

        public UrlValidator​(long options)
        Constructs a new instance 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​(RegexValidator authorityValidator,
                            long options)
        Constructs a new instance with the given validation options.
        Parameters:
        authorityValidator - Regular expression validator used to validate the authority part This allows the user to override the standard set of domains.
        options - Validation options. Set using the public constants of this class. To set multiple options, simply add them together:

        ALLOW_2_SLASHES + NO_FRAGMENTS

        enables both of those options.
      • 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​(java.lang.String[] schemes,
                            long options)
        Behavior of validation is modified by passing in options:
        Parameters:
        schemes - The set of valid schemes. Ignored if the ALLOW_ALL_SCHEMES option is set.
        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,
                            RegexValidator authorityValidator,
                            long options)
        Customizable constructor. Validation behavior is modified by passing in options.
        Parameters:
        schemes - the set of valid schemes. Ignored if the ALLOW_ALL_SCHEMES option is set.
        authorityValidator - Regular expression validator used to validate the authority part
        options - Validation options. Set using the public constants of this class. To set multiple options, simply add them together:

        ALLOW_2_SLASHES + NO_FRAGMENTS

        enables both of those options.
      • UrlValidator

        public UrlValidator​(java.lang.String[] schemes,
                            RegexValidator authorityValidator,
                            long options,
                            DomainValidator domainValidator)
        Customizable constructor. Validation behavior is modified by passing in options.
        Parameters:
        schemes - the set of valid schemes. Ignored if the ALLOW_ALL_SCHEMES option is set.
        authorityValidator - Regular expression validator used to validate the authority part
        options - Validation options. Set using the public constants of this class. To set multiple options, simply add them together:

        ALLOW_2_SLASHES + NO_FRAGMENTS

        enables both of those options.
        domainValidator - the DomainValidator to use; must agree with ALLOW_LOCAL_URLS setting
        Since:
        1.7
    • Method Detail

      • getInstance

        public static UrlValidator getInstance()
        Returns the singleton instance of this class with default schemes and options.
        Returns:
        singleton instance with default schemes and options
      • 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.
      • isValid

        public boolean isValid​(java.lang.String value)

        Checks if a field has a valid URL address.

        Note that the method calls #isValidAuthority() which checks that the domain is valid.
        Parameters:
        value - The value validation is being performed on. A null value is considered invalid.
        Returns:
        true if the URL is 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. Note: this implementation validates the domain unless a RegexValidator was provided. If a RegexValidator was supplied, and it matches, then the authority is regarded as valid with no further checks, otherwise the method checks against the AUTHORITY_PATTERN and the DomainValidator (ALLOW_LOCAL_URLS)
        Parameters:
        authority - Authority value to validate, allows IDN
        Returns:
        true if authority (hostname and port) 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.
      • 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.
      • isValidScheme

        protected boolean isValidScheme​(java.lang.String scheme)
        Validate scheme. If schemes[] was initialized to a non-null, then only those schemes are allowed. Otherwise, the default schemes are "http", "https", "ftp". Matching is case-blind.
        Parameters:
        scheme - The scheme to validate. A null value is considered invalid.
        Returns:
        true if valid.