urlvalidator.java

java验证框架 java验证框架

        if (!matchUrlPat.match(URL_PATTERN, value)) {
            return false;
        }

        if (!isValidScheme(matchUrlPat.group(PARSE_URL_SCHEME))) {
            return false;
        }

        if (!isValidAuthority(matchUrlPat.group(PARSE_URL_AUTHORITY))) {
            return false;
        }

        if (!isValidPath(matchUrlPat.group(PARSE_URL_PATH))) {
            return false;
        }

        if (!isValidQuery(matchUrlPat.group(PARSE_URL_QUERY))) {
            return false;
        }

        if (!isValidFragment(matchUrlPat.group(PARSE_URL_FRAGMENT))) {
            return false;
        }

        return true;
    }

    /**
     * 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.
     * @param scheme The scheme to validate.  A <code>null</code> value is considered
     * invalid.
     * @return true if valid.
     */
    protected boolean isValidScheme(String scheme) {
        if (scheme == null) {
            return false;
        }

        Perl5Util schemeMatcher = new Perl5Util();
        if (!schemeMatcher.match(SCHEME_PATTERN, scheme)) {
            return false;
        }

        if (this.options.isOff(ALLOW_ALL_SCHEMES)) {

            if (!this.allowedSchemes.contains(scheme)) {
                return false;
            }
        }

        return true;
    }

    /**
     * Returns true if the authority is properly formatted.  An authority is the combination
     * of hostname and port.  A <code>null</code> authority value is considered invalid.
     * @param authority Authority value to validate.
     * @return true if authority (hostname and port) is valid.
     */
    protected boolean isValidAuthority(String authority) {
        if (authority == null) {
            return false;
        }

        Perl5Util authorityMatcher = new Perl5Util();
        Perl5Util matchIPV4Pat = new Perl5Util();

        if (!authorityMatcher.match(AUTHORITY_PATTERN, authority)) {
            return false;
        }

        boolean ipV4Address = false;
        boolean hostname = false;
// check if authority is IP address or hostname
        String hostIP = authorityMatcher.group(PARSE_AUTHORITY_HOST_IP);
        ipV4Address = matchIPV4Pat.match(IP_V4_DOMAIN_PATTERN, hostIP);

        if (ipV4Address) {
            // this is an IP address so check components
            for (int i = 1; i <= 4; i++) {
                String ipSegment = matchIPV4Pat.group(i);
                if (ipSegment == null || ipSegment.length() <= 0) {
                    return false;
                }

                try {
                    if (Integer.parseInt(ipSegment) > 255) {
                        return false;
                    }
                } catch(NumberFormatException e) {
                    return false;
                }

            }
        } else {
            // Domain is hostname name
            Perl5Util domainMatcher = new Perl5Util();
            hostname = domainMatcher.match(DOMAIN_PATTERN, hostIP);
        }

//rightmost hostname will never start with a digit.
        if (hostname) {
            // LOW-TECH FIX FOR VALIDATOR-202
            // TODO: Rewrite to use ArrayList and .add semantics: see VALIDATOR-203
            char[] chars = hostIP.toCharArray();
            int size = 1;
            for(int i=0; i<chars.length; i++) {
                if(chars[i] == '.') {
                    size++;
                }
            }
            String[] domainSegment = new String[size];
            boolean match = true;
            int segmentCount = 0;
            int segmentLength = 0;
            Perl5Util atomMatcher = new Perl5Util();

            while (match) {
                match = atomMatcher.match(ATOM_PATTERN, hostIP);
                if (match) {
                    domainSegment[segmentCount] = atomMatcher.group(1);
                    segmentLength = domainSegment[segmentCount].length() + 1;
                    hostIP =
                            (segmentLength >= hostIP.length())
                            ? ""
                            : hostIP.substring(segmentLength);

                    segmentCount++;
                }
            }
            String topLevel = domainSegment[segmentCount - 1];
            if (topLevel.length() < 2 || topLevel.length() > 4) {
                return false;
            }

            // First letter of top level must be a alpha
            Perl5Util alphaMatcher = new Perl5Util();
            if (!alphaMatcher.match(ALPHA_PATTERN, topLevel.substring(0, 1))) {
                return false;
            }

            // Make sure there's a host name preceding the authority.
            if (segmentCount < 2) {
                return false;
            }
        }

        if (!hostname && !ipV4Address) {
            return false;
        }

        String port = authorityMatcher.group(PARSE_AUTHORITY_PORT);
        if (port != null) {
            Perl5Util portMatcher = new Perl5Util();
            if (!portMatcher.match(PORT_PATTERN, port)) {
                return false;
            }
        }

        String extra = authorityMatcher.group(PARSE_AUTHORITY_EXTRA);
        if (!GenericValidator.isBlankOrNull(extra)) {
            return false;
        }

        return true;
    }

    /**
     * Returns true if the path is valid.  A <code>null</code> value is considered invalid.
     * @param path Path value to validate.
     * @return true if path is valid.
     */
    protected boolean isValidPath(String path) {
        if (path == null) {
            return false;
        }

        Perl5Util pathMatcher = new Perl5Util();

        if (!pathMatcher.match(PATH_PATTERN, path)) {
            return false;
        }

        int slash2Count = countToken("//", path);
        if (this.options.isOff(ALLOW_2_SLASHES) && (slash2Count > 0)) {
            return false;
        }

        int slashCount = countToken("/", path);
        int dot2Count = countToken("..", path);
        if (dot2Count > 0) {
            if ((slashCount - slash2Count - 1) <= dot2Count) {
                return false;
            }
        }

        return true;
    }

    /**
     * Returns true if the query is null or it's a properly formatted query string.
     * @param query Query value to validate.
     * @return true if query is valid.
     */
    protected boolean isValidQuery(String query) {
        if (query == null) {
            return true;
        }

        Perl5Util queryMatcher = new Perl5Util();
        return queryMatcher.match(QUERY_PATTERN, query);
    }

    /**
     * Returns true if the given fragment is null or fragments are allowed.
     * @param fragment Fragment value to validate.
     * @return true if fragment is valid.
     */
    protected boolean isValidFragment(String fragment) {
        if (fragment == null) {
            return true;
        }

        return this.options.isOff(NO_FRAGMENTS);
    }

    /**
     * Returns the number of times the token appears in the target.
     * @param token Token value to be counted.
     * @param target Target value to count tokens in.
     * @return the number of tokens.
     */
    protected int countToken(String token, String target) {
        int tokenIndex = 0;
        int count = 0;
        while (tokenIndex != -1) {
            tokenIndex = target.indexOf(token, tokenIndex);
            if (tokenIndex > -1) {
                tokenIndex++;
                count++;
            }
        }
        return count;
    }
}