common/src/main/java/org/apache/abdera2/common/iri/IRI.java - abdera - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  The ASF licenses this file to You
  * under the Apache License, Version 2.0 (the "License"); you may not
  * use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.  For additional information regarding
  * copyright in this work, please see the NOTICE file in the top level
  * directory of this distribution.
  */
 package org.apache.abdera2.common.iri;

 import java.io.IOException;
 import java.io.Serializable;
 import java.net.MalformedURLException;
 import java.net.URISyntaxException;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 import org.apache.abdera2.common.text.CharUtils;
 import org.apache.abdera2.common.text.InvalidCharacterException;
 import org.apache.abdera2.common.text.NormalizationForm;
 import org.apache.abdera2.common.text.UrlEncoding;
 import org.apache.abdera2.common.text.CharUtils.Profile;

 import com.ibm.icu.text.IDNA;

 public final class IRI implements Serializable, Cloneable {

     private static final long serialVersionUID = -4530530782760282284L;
     protected Scheme _scheme;
     private String authority;
     private String userinfo;
     private String host;
     private int port = -1;
     private String path;
     private String query;
     private String fragment;

     private String a_host;
     private String a_fragment;
     private String a_path;
     private String a_query;
     private String a_userinfo;
     private String a_authority;

     public IRI(java.net.URL url) {
         this(url.toString());
     }

     public IRI(java.net.URI uri) {
         this(uri.toString());
     }

     public IRI(String iri) {
         parse(iri);
         init();
     }

     public IRI(String iri, NormalizationForm nf) throws IOException {
         this(nf.normalize(iri));
     }

     public IRI(String scheme, String userinfo, String host, int port, String path, String query, String fragment) {
         this._scheme = SchemeRegistry.get(scheme);
         this.userinfo = userinfo;
         this.host = host;
         this.port = port;
         this.path = path;
         this.query = query;
         this.fragment = fragment;
         StringBuilder buf = new StringBuilder();
         buildAuthority(buf, userinfo, host, port);
         this.authority = (buf.length() != 0) ? buf.toString() : null;
         init();
     }

     public IRI(String scheme, String authority, String path, String query, String fragment) {
         this._scheme = SchemeRegistry.get(scheme);
         this.authority = authority;
         this.path = path;
         this.query = query;
         this.fragment = fragment;
         parseAuthority();
         init();
     }

     public IRI(String scheme, String host, String path, String fragment) {
         this(scheme, null, host, -1, path, null, fragment);
     }

     IRI(Scheme _scheme,
         String authority,
         String userinfo,
         String host,
         int port,
         String path,
         String query,
         String fragment) {
         this._scheme = _scheme;
         this.authority = authority;
         this.userinfo = userinfo;
         this.host = host;
         this.port = port;
         this.path = path;
         this.query = query;
         this.fragment = fragment;
         init();
     }

     private void init() {
         if (host != null && host.startsWith("[")) {
             a_host = host;
         } else {
             try {
                 if (getHost() != null) {
                   a_host = IDNA.convertIDNToASCII(host, IDNA.USE_STD3_RULES).toString();
                 }
             } catch (Throwable t) {
                 throw new IRISyntaxException("Invalid Internationalized Domain Name");
             }
         }
         a_fragment = UrlEncoding.encode(fragment, Profile.FRAGMENT);
         a_path = UrlEncoding.encode(path, Profile.PATH);
         a_query = UrlEncoding.encode(query, Profile.QUERY, Profile.PATH);
         a_userinfo = UrlEncoding.encode(userinfo, Profile.USERINFO);
         a_authority = buildASCIIAuthority();
     }

     @Override
     public int hashCode() {
         final int PRIME = 31;
         int result = 1;
         result = PRIME * result + ((authority == null) ? 0 : authority.hashCode());
         result = PRIME * result + ((fragment == null) ? 0 : fragment.hashCode());
         result = PRIME * result + ((host == null) ? 0 : host.hashCode());
         result = PRIME * result + ((path == null) ? 0 : path.hashCode());
         result = PRIME * result + port;
         result = PRIME * result + ((query == null) ? 0 : query.hashCode());
         result = PRIME * result + ((_scheme == null) ? 0 : _scheme.hashCode());
         result = PRIME * result + ((userinfo == null) ? 0 : userinfo.hashCode());
         return result;
     }

     @Override
     public boolean equals(Object obj) {
         if (this == obj)
             return true;
         if (obj == null)
             return false;
         if (getClass() != obj.getClass())
             return false;
         final IRI other = (IRI)obj;
         if (authority == null) {
             if (other.authority != null)
                 return false;
         } else if (!authority.equals(other.authority))
             return false;
         if (fragment == null) {
             if (other.fragment != null)
                 return false;
         } else if (!fragment.equals(other.fragment))
             return false;
         if (host == null) {
             if (other.host != null)
                 return false;
         } else if (!host.equals(other.host))
             return false;
         if (path == null) {
             if (other.path != null)
                 return false;
         } else if (!path.equals(other.path))
             return false;
         if (port != other.port)
             return false;
         if (query == null) {
             if (other.query != null)
                 return false;
         } else if (!query.equals(other.query))
             return false;
         if (_scheme == null) {
             if (other._scheme != null)
                 return false;
         } else if (!_scheme.equals(other._scheme))
             return false;
         if (userinfo == null) {
             if (other.userinfo != null)
                 return false;
         } else if (!userinfo.equals(other.userinfo))
             return false;
         return true;
     }

     public String getAuthority() {
         return (authority != null && authority.length() > 0) ? authority : null;
     }

     public String getFragment() {
         return fragment;
     }

     public String getHost() {
         return (host != null && host.length() > 0) ? host : null;
     }

     public String getASCIIHost() {
         return (a_host != null && a_host.length() > 0) ? a_host : null;
     }

     public String getPath() {
         return path;
     }

     public int getPort() {
         return port;
     }

     public String getQuery() {
         return query;
     }

     public String getScheme() {
       return _scheme != null ? _scheme.name() : null;
     }

     public String getSchemeSpecificPart() {
         return buildSchemeSpecificPart(authority, path, query, fragment);
     }

     public String getUserInfo() {
         return userinfo;
     }

     void buildAuthority(StringBuilder buf, String aui, String ah, int port) {
         if (aui != null && aui.length() != 0)
             buf.append(aui)
                .append('@');
         if (ah != null && ah.length() != 0)
             buf.append(ah);
         if (port != -1)
             buf.append(':')
                .append(port);
     }

     private String buildASCIIAuthority() {
         if (_scheme instanceof HttpScheme) {
             StringBuilder buf = new StringBuilder();
             buildAuthority(buf, getASCIIUserInfo(), getASCIIHost(), getPort());
             return buf.toString();
         } else {
             return UrlEncoding.encode(authority, Profile.AUTHORITY);
         }
     }

     public String getASCIIAuthority() {
         return (a_authority != null && a_authority.length() > 0) ? a_authority : null;
     }

     public String getASCIIFragment() {
         return a_fragment;
     }

     public String getASCIIPath() {
         return a_path;
     }

     public String getASCIIQuery() {
         return a_query;
     }

     public String getASCIIUserInfo() {
         return a_userinfo;
     }

     public String getASCIISchemeSpecificPart() {
         return buildSchemeSpecificPart(a_authority, a_path, a_query, a_fragment);
     }

     private String buildSchemeSpecificPart(String authority, String path, String query, String fragment) {
         StringBuilder buf = new StringBuilder();
         if (authority != null)
             buf.append("//")
                .append(authority);
         if (path != null && path.length() != 0)
             buf.append(path);
         if (query != null)
             buf.append('?')
                .append(query);
         if (fragment != null)
             buf.append('#')
                .append(fragment);
         return buf.toString();
     }

     public Object clone() {
         try {
             return super.clone();
         } catch (CloneNotSupportedException e) {
             return new IRI(toString()); // not going to happen, but we have to
                                         // catch it just in case
         }
     }

     public boolean isAbsolute() {
         return _scheme != null;
     }

     public boolean isOpaque() {
         return path == null;
     }

     public static IRI relativize(IRI b, IRI c) {
         if (c.isOpaque() || b.isOpaque())
             return c;
         if ((b._scheme == null && c._scheme != null) ||
             (b._scheme != null && c._scheme == null) ||
             (b._scheme != null && c._scheme != null &&
              !b._scheme.equals(c._scheme)))
             return c;
         String bpath = normalize(b.getPath());
         String cpath = normalize(c.getPath());
         bpath = (bpath != null) ? bpath : "/";
         cpath = (cpath != null) ? cpath : "/";
         if (!bpath.equals(cpath)) {
             if (bpath.charAt(bpath.length() - 1) != '/')
                 bpath += "/";
             if (!cpath.startsWith(bpath))
                 return c;
         }
         IRI iri =
             new IRI(null, null, null, null, -1, normalize(cpath.substring(bpath.length())), c.getQuery(), c
                 .getFragment());
         return iri;
     }

     public IRI relativize(IRI iri) {
         return relativize(this, iri);
     }

     public boolean isPathAbsolute() {
         String path = getPath();
         return (path != null) && path.length() > 0 && path.charAt(0) == '/';
     }

     public boolean isSameDocumentReference() {
         return _scheme == null && authority == null
             && (path == null || path.length() == 0 || path.equals("."))
             && query == null;
     }

     public static IRI resolve(IRI b, String c) throws IOException {
         return resolve(b, new IRI(c));
     }

     public static IRI resolve(IRI b, IRI c) {

         if (c == null)
             return null;
         if ("".equals(c.toString()) || "#".equals(c.toString())
             || ".".equals(c.toString())
             || "./".equals(c.toString()))
             return b;
         if (b == null)
             return c;

         if (c.isOpaque() || b.isOpaque())
             return c;
         if (c.isSameDocumentReference()) {
             String cfragment = c.getFragment();
             String bfragment = b.getFragment();
             if ((cfragment == null && bfragment == null) || (cfragment != null && cfragment.equals(bfragment))) {
                 return (IRI)b.clone();
             } else {
                 return new IRI(b._scheme, b.getAuthority(), b.getUserInfo(), b.getHost(), b.getPort(),
                                normalize(b.getPath()), b.getQuery(), cfragment);
             }
         }
         if (c.isAbsolute())
             return c;

         Scheme _scheme = b._scheme;
         String query = c.getQuery();
         String fragment = c.getFragment();
         String userinfo = null;
         String authority = null;
         String host = null;
         int port = -1;
         String path = null;
         if (c.getAuthority() == null) {
             authority = b.getAuthority();
             userinfo = b.getUserInfo();
             host = b.getHost();
             port = b.getPort();
             path = c.isPathAbsolute() ? normalize(c.getPath()) : resolve(b.getPath(), c.getPath());
         } else {
             authority = c.getAuthority();
             userinfo = c.getUserInfo();
             host = c.getHost();
             port = c.getPort();
             path = normalize(c.getPath());
         }
         return new IRI(_scheme, authority, userinfo, host, port, path, query, fragment);
     }

     public IRI normalize() {
         return normalize(this);
     }

     public static String normalizeString(String iri) {
         return normalize(new IRI(iri)).toString();
     }

     public static IRI normalize(IRI iri) {
         if (iri.isOpaque() || iri.getPath() == null)
             return iri;
         IRI normalized = null;
         if (iri._scheme != null)
             normalized = iri._scheme.normalize(iri);
         return (normalized != null) ?
             normalized :
             new IRI(
                 iri._scheme,
                 iri.getAuthority(),
                 iri.getUserInfo(),
                 iri.getHost(),
                 iri.getPort(),
                 normalize(iri.getPath()),
                 UrlEncoding.encode(
                     UrlEncoding.decode(
                       iri.getQuery()),
                     Profile.IQUERY),
                 UrlEncoding.encode(
                     UrlEncoding.decode(
                       iri.getFragment()),
                     Profile.IFRAGMENT));
     }

     protected static String normalize(String path) {
       if (path == null || path.length() == 0)
           return "/";
       String[] segments = path.split("/");
       boolean trailingslash =
         path.matches(".*/\\.{1}|.*\\./\\.{2}|.*/{1}$");
       int pos = 0;
       for (String segment : segments)
           if ("..".equals(segment)) {
               pos = (pos-1>-1)?pos-1:0;
               segments[pos] = null;
           } else if (!".".equals(segment))
             segments[pos++] = segment;
       if (pos < segments.length)
         segments[pos] = null;
       StringBuilder buf = new StringBuilder();
       buf.ensureCapacity(path.length());
       if (pos != 0) {
         pos = 0;
         while (pos<segments.length) {
           String segment = segments[pos++];
           if (segment == null) break;
           if(pos-1>0||segment.length()>0)
             buf.append('/');
           buf.append(
                UrlEncoding.encode(
                  UrlEncoding.decode(segment),
                    Profile.IPATHNODELIMS_SEG));
         }
       }
       if (trailingslash && buf.length() > 1)
         buf.append('/');
       return buf.toString();
     }

     private static String resolve(String bpath, String cpath) {
         if (bpath == null && cpath == null)
             return null;
         if (bpath == null && cpath != null) {
             return (!cpath.startsWith("/")) ? "/" + cpath : cpath;
         }
         if (bpath != null && cpath == null)
             return bpath;
         if (bpath.equals(cpath))
           return bpath;
         StringBuilder buf = new StringBuilder("");
         int n = bpath.lastIndexOf('/');
         if (n > -1)
             buf.append(bpath.substring(0, n + 1));
         if (cpath.length() != 0)
             buf.append(cpath);
         if (buf.charAt(0) != '/')
             buf.insert(0, '/');
         return normalize(buf.toString());
     }

     public IRI resolve(IRI iri) {
         return resolve(this, iri);
     }

     public IRI resolve(String iri) {
         return resolve(this, new IRI(iri));
     }

     public String toString() {
         StringBuilder buf = new StringBuilder();
         String scheme = getScheme();
         if (scheme != null && scheme.length() != 0)
             buf.append(scheme)
                .append(':');
         buf.append(getSchemeSpecificPart());
         return UrlEncoding.encode(buf.toString(), Profile.SCHEMESPECIFICPART);
     }

     public String toASCIIString() {
         StringBuilder buf = new StringBuilder();
         String scheme = getScheme();
         if (scheme != null && scheme.length() != 0)
             buf.append(scheme)
                .append(':');
         buf.append(getASCIISchemeSpecificPart());
         return buf.toString();
     }

     public java.net.URI toURI() throws URISyntaxException {
         return new java.net.URI(toASCIIString());
     }

     public java.net.URL toURL() throws MalformedURLException, URISyntaxException {
         return toURI().toURL();
     }

     private void parseAuthority() {
         if (authority != null) {
             Matcher auth = AUTHORITYPATTERN.matcher(authority);
             if (auth.find()) {
                 userinfo = auth.group(1);
                 host = auth.group(2);
                 if (auth.group(3) != null)
                     port = Integer.parseInt(auth.group(3));
                 else
                     port = -1;
             }
             try {
                 CharUtils.verify(userinfo, Profile.IUSERINFO);
                 CharUtils.verify(host, Profile.IHOST);
             } catch (InvalidCharacterException e) {
                 throw new IRISyntaxException(e);
             }
         }
     }

     private void parse(String iri) {
         try {
             Matcher irim = IRIPATTERN.matcher(iri);
             if (irim.find()) {
                 String scheme = irim.group(1);
                 _scheme = SchemeRegistry.get(scheme);
                 authority = irim.group(2);
                 path = irim.group(3);
                 query = irim.group(4);
                 fragment = irim.group(5);
                 parseAuthority();
                 try {
                     CharUtils.verify(scheme, Profile.SCHEME);
                     CharUtils.verify(path, Profile.IPATH);
                     CharUtils.verify(query, Profile.IQUERY);
                     CharUtils.verify(fragment, Profile.IFRAGMENT);
                 } catch (InvalidCharacterException e) {
                     throw new IRISyntaxException(e);
                 }
             } else {
                 throw new IRISyntaxException("Invalid Syntax");
             }
         } catch (IRISyntaxException e) {
             throw e;
         } catch (Exception e) {
             throw new IRISyntaxException(e);
         }
     }

     private static final Pattern IRIPATTERN =
         Pattern.compile("^(?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\\?([^#]*))?(?:#(.*))?");

     private static final Pattern AUTHORITYPATTERN =
         Pattern.compile("^(?:(.*)?@)?((?:\\[.*\\])|(?:[^:]*))?(?::(\\d+))?");

     /**
      * Returns a new IRI with a trailing slash appended to the path, if necessary.
      * The query and fragment are omitted from the resulting IRI
      */
     public IRI trailingSlash() {
       return this.resolve(path + "/");
     }

 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. The ASF licenses this file to You
	* under the Apache License, Version 2.0 (the "License"); you may not
	* use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License. For additional information regarding
	* copyright in this work, please see the NOTICE file in the top level
	* directory of this distribution.
	*/
	package org.apache.abdera2.common.iri;

	import java.io.IOException;
	import java.io.Serializable;
	import java.net.MalformedURLException;
	import java.net.URISyntaxException;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;

	import org.apache.abdera2.common.text.CharUtils;
	import org.apache.abdera2.common.text.InvalidCharacterException;
	import org.apache.abdera2.common.text.NormalizationForm;
	import org.apache.abdera2.common.text.UrlEncoding;
	import org.apache.abdera2.common.text.CharUtils.Profile;

	import com.ibm.icu.text.IDNA;

	public final class IRI implements Serializable, Cloneable {

	private static final long serialVersionUID = -4530530782760282284L;
	protected Scheme _scheme;
	private String authority;
	private String userinfo;
	private String host;
	private int port = -1;
	private String path;
	private String query;
	private String fragment;

	private String a_host;
	private String a_fragment;
	private String a_path;
	private String a_query;
	private String a_userinfo;
	private String a_authority;

	public IRI(java.net.URL url) {
	this(url.toString());
	}

	public IRI(java.net.URI uri) {
	this(uri.toString());
	}

	public IRI(String iri) {
	parse(iri);
	init();
	}

	public IRI(String iri, NormalizationForm nf) throws IOException {
	this(nf.normalize(iri));
	}

	public IRI(String scheme, String userinfo, String host, int port, String path, String query, String fragment) {
	this._scheme = SchemeRegistry.get(scheme);
	this.userinfo = userinfo;
	this.host = host;
	this.port = port;
	this.path = path;
	this.query = query;
	this.fragment = fragment;
	StringBuilder buf = new StringBuilder();
	buildAuthority(buf, userinfo, host, port);
	this.authority = (buf.length() != 0) ? buf.toString() : null;
	init();
	}

	public IRI(String scheme, String authority, String path, String query, String fragment) {
	this._scheme = SchemeRegistry.get(scheme);
	this.authority = authority;
	this.path = path;
	this.query = query;
	this.fragment = fragment;
	parseAuthority();
	init();
	}

	public IRI(String scheme, String host, String path, String fragment) {
	this(scheme, null, host, -1, path, null, fragment);
	}

	IRI(Scheme _scheme,
	String authority,
	String userinfo,
	String host,
	int port,
	String path,
	String query,
	String fragment) {
	this._scheme = _scheme;
	this.authority = authority;
	this.userinfo = userinfo;
	this.host = host;
	this.port = port;
	this.path = path;
	this.query = query;
	this.fragment = fragment;
	init();
	}

	private void init() {
	if (host != null && host.startsWith("[")) {
	a_host = host;
	} else {
	try {
	if (getHost() != null) {
	a_host = IDNA.convertIDNToASCII(host, IDNA.USE_STD3_RULES).toString();
	}
	} catch (Throwable t) {
	throw new IRISyntaxException("Invalid Internationalized Domain Name");
	}
	}
	a_fragment = UrlEncoding.encode(fragment, Profile.FRAGMENT);
	a_path = UrlEncoding.encode(path, Profile.PATH);
	a_query = UrlEncoding.encode(query, Profile.QUERY, Profile.PATH);
	a_userinfo = UrlEncoding.encode(userinfo, Profile.USERINFO);
	a_authority = buildASCIIAuthority();
	}

	@Override
	public int hashCode() {
	final int PRIME = 31;
	int result = 1;
	result = PRIME * result + ((authority == null) ? 0 : authority.hashCode());
	result = PRIME * result + ((fragment == null) ? 0 : fragment.hashCode());
	result = PRIME * result + ((host == null) ? 0 : host.hashCode());
	result = PRIME * result + ((path == null) ? 0 : path.hashCode());
	result = PRIME * result + port;
	result = PRIME * result + ((query == null) ? 0 : query.hashCode());
	result = PRIME * result + ((_scheme == null) ? 0 : _scheme.hashCode());
	result = PRIME * result + ((userinfo == null) ? 0 : userinfo.hashCode());
	return result;
	}

	@Override
	public boolean equals(Object obj) {
	if (this == obj)
	return true;
	if (obj == null)
	return false;
	if (getClass() != obj.getClass())
	return false;
	final IRI other = (IRI)obj;
	if (authority == null) {
	if (other.authority != null)
	return false;
	} else if (!authority.equals(other.authority))
	return false;
	if (fragment == null) {
	if (other.fragment != null)
	return false;
	} else if (!fragment.equals(other.fragment))
	return false;
	if (host == null) {
	if (other.host != null)
	return false;
	} else if (!host.equals(other.host))
	return false;
	if (path == null) {
	if (other.path != null)
	return false;
	} else if (!path.equals(other.path))
	return false;
	if (port != other.port)
	return false;
	if (query == null) {
	if (other.query != null)
	return false;
	} else if (!query.equals(other.query))
	return false;
	if (_scheme == null) {
	if (other._scheme != null)
	return false;
	} else if (!_scheme.equals(other._scheme))
	return false;
	if (userinfo == null) {
	if (other.userinfo != null)
	return false;
	} else if (!userinfo.equals(other.userinfo))
	return false;
	return true;
	}

	public String getAuthority() {
	return (authority != null && authority.length() > 0) ? authority : null;
	}

	public String getFragment() {
	return fragment;
	}

	public String getHost() {
	return (host != null && host.length() > 0) ? host : null;
	}

	public String getASCIIHost() {
	return (a_host != null && a_host.length() > 0) ? a_host : null;
	}

	public String getPath() {
	return path;
	}

	public int getPort() {
	return port;
	}

	public String getQuery() {
	return query;
	}

	public String getScheme() {
	return _scheme != null ? _scheme.name() : null;
	}

	public String getSchemeSpecificPart() {
	return buildSchemeSpecificPart(authority, path, query, fragment);
	}

	public String getUserInfo() {
	return userinfo;
	}

	void buildAuthority(StringBuilder buf, String aui, String ah, int port) {
	if (aui != null && aui.length() != 0)
	buf.append(aui)
	.append('@');
	if (ah != null && ah.length() != 0)
	buf.append(ah);
	if (port != -1)
	buf.append(':')
	.append(port);
	}

	private String buildASCIIAuthority() {
	if (_scheme instanceof HttpScheme) {
	StringBuilder buf = new StringBuilder();
	buildAuthority(buf, getASCIIUserInfo(), getASCIIHost(), getPort());
	return buf.toString();
	} else {
	return UrlEncoding.encode(authority, Profile.AUTHORITY);
	}
	}

	public String getASCIIAuthority() {
	return (a_authority != null && a_authority.length() > 0) ? a_authority : null;
	}

	public String getASCIIFragment() {
	return a_fragment;
	}

	public String getASCIIPath() {
	return a_path;
	}

	public String getASCIIQuery() {
	return a_query;
	}

	public String getASCIIUserInfo() {
	return a_userinfo;
	}

	public String getASCIISchemeSpecificPart() {
	return buildSchemeSpecificPart(a_authority, a_path, a_query, a_fragment);
	}

	private String buildSchemeSpecificPart(String authority, String path, String query, String fragment) {
	StringBuilder buf = new StringBuilder();
	if (authority != null)
	buf.append("//")
	.append(authority);
	if (path != null && path.length() != 0)
	buf.append(path);
	if (query != null)
	buf.append('?')
	.append(query);
	if (fragment != null)
	buf.append('#')
	.append(fragment);
	return buf.toString();
	}

	public Object clone() {
	try {
	return super.clone();
	} catch (CloneNotSupportedException e) {
	return new IRI(toString()); // not going to happen, but we have to
	// catch it just in case
	}
	}

	public boolean isAbsolute() {
	return _scheme != null;
	}

	public boolean isOpaque() {
	return path == null;
	}

	public static IRI relativize(IRI b, IRI c) {
	if (c.isOpaque() \|\| b.isOpaque())
	return c;
	if ((b._scheme == null && c._scheme != null) \|\|
	(b._scheme != null && c._scheme == null) \|\|
	(b._scheme != null && c._scheme != null &&
	!b._scheme.equals(c._scheme)))
	return c;
	String bpath = normalize(b.getPath());
	String cpath = normalize(c.getPath());
	bpath = (bpath != null) ? bpath : "/";
	cpath = (cpath != null) ? cpath : "/";
	if (!bpath.equals(cpath)) {
	if (bpath.charAt(bpath.length() - 1) != '/')
	bpath += "/";
	if (!cpath.startsWith(bpath))
	return c;
	}
	IRI iri =
	new IRI(null, null, null, null, -1, normalize(cpath.substring(bpath.length())), c.getQuery(), c
	.getFragment());
	return iri;
	}

	public IRI relativize(IRI iri) {
	return relativize(this, iri);
	}

	public boolean isPathAbsolute() {
	String path = getPath();
	return (path != null) && path.length() > 0 && path.charAt(0) == '/';
	}

	public boolean isSameDocumentReference() {
	return _scheme == null && authority == null
	&& (path == null \|\| path.length() == 0 \|\| path.equals("."))
	&& query == null;
	}

	public static IRI resolve(IRI b, String c) throws IOException {
	return resolve(b, new IRI(c));
	}

	public static IRI resolve(IRI b, IRI c) {

	if (c == null)
	return null;
	if ("".equals(c.toString()) \|\| "#".equals(c.toString())
	\|\| ".".equals(c.toString())
	\|\| "./".equals(c.toString()))
	return b;
	if (b == null)
	return c;

	if (c.isOpaque() \|\| b.isOpaque())
	return c;
	if (c.isSameDocumentReference()) {
	String cfragment = c.getFragment();
	String bfragment = b.getFragment();
	if ((cfragment == null && bfragment == null) \|\| (cfragment != null && cfragment.equals(bfragment))) {
	return (IRI)b.clone();
	} else {
	return new IRI(b._scheme, b.getAuthority(), b.getUserInfo(), b.getHost(), b.getPort(),
	normalize(b.getPath()), b.getQuery(), cfragment);
	}
	}
	if (c.isAbsolute())
	return c;

	Scheme _scheme = b._scheme;
	String query = c.getQuery();
	String fragment = c.getFragment();
	String userinfo = null;
	String authority = null;
	String host = null;
	int port = -1;
	String path = null;
	if (c.getAuthority() == null) {
	authority = b.getAuthority();
	userinfo = b.getUserInfo();
	host = b.getHost();
	port = b.getPort();
	path = c.isPathAbsolute() ? normalize(c.getPath()) : resolve(b.getPath(), c.getPath());
	} else {
	authority = c.getAuthority();
	userinfo = c.getUserInfo();
	host = c.getHost();
	port = c.getPort();
	path = normalize(c.getPath());
	}
	return new IRI(_scheme, authority, userinfo, host, port, path, query, fragment);
	}

	public IRI normalize() {
	return normalize(this);
	}

	public static String normalizeString(String iri) {
	return normalize(new IRI(iri)).toString();
	}

	public static IRI normalize(IRI iri) {
	if (iri.isOpaque() \|\| iri.getPath() == null)
	return iri;
	IRI normalized = null;
	if (iri._scheme != null)
	normalized = iri._scheme.normalize(iri);
	return (normalized != null) ?
	normalized :
	new IRI(
	iri._scheme,
	iri.getAuthority(),
	iri.getUserInfo(),
	iri.getHost(),
	iri.getPort(),
	normalize(iri.getPath()),
	UrlEncoding.encode(
	UrlEncoding.decode(
	iri.getQuery()),
	Profile.IQUERY),
	UrlEncoding.encode(
	UrlEncoding.decode(
	iri.getFragment()),
	Profile.IFRAGMENT));
	}

	protected static String normalize(String path) {
	if (path == null \|\| path.length() == 0)
	return "/";
	String[] segments = path.split("/");
	boolean trailingslash =
	path.matches("./\\.{1}\|.\\./\\.{2}\|.*/{1}$");
	int pos = 0;
	for (String segment : segments)
	if ("..".equals(segment)) {
	pos = (pos-1>-1)?pos-1:0;
	segments[pos] = null;
	} else if (!".".equals(segment))
	segments[pos++] = segment;
	if (pos < segments.length)
	segments[pos] = null;
	StringBuilder buf = new StringBuilder();
	buf.ensureCapacity(path.length());
	if (pos != 0) {
	pos = 0;
	while (pos<segments.length) {
	String segment = segments[pos++];
	if (segment == null) break;
	if(pos-1>0\|\|segment.length()>0)
	buf.append('/');
	buf.append(
	UrlEncoding.encode(
	UrlEncoding.decode(segment),
	Profile.IPATHNODELIMS_SEG));
	}
	}
	if (trailingslash && buf.length() > 1)
	buf.append('/');
	return buf.toString();
	}

	private static String resolve(String bpath, String cpath) {
	if (bpath == null && cpath == null)
	return null;
	if (bpath == null && cpath != null) {
	return (!cpath.startsWith("/")) ? "/" + cpath : cpath;
	}
	if (bpath != null && cpath == null)
	return bpath;
	if (bpath.equals(cpath))
	return bpath;
	StringBuilder buf = new StringBuilder("");
	int n = bpath.lastIndexOf('/');
	if (n > -1)
	buf.append(bpath.substring(0, n + 1));
	if (cpath.length() != 0)
	buf.append(cpath);
	if (buf.charAt(0) != '/')
	buf.insert(0, '/');
	return normalize(buf.toString());
	}

	public IRI resolve(IRI iri) {
	return resolve(this, iri);
	}

	public IRI resolve(String iri) {
	return resolve(this, new IRI(iri));
	}

	public String toString() {
	StringBuilder buf = new StringBuilder();
	String scheme = getScheme();
	if (scheme != null && scheme.length() != 0)
	buf.append(scheme)
	.append(':');
	buf.append(getSchemeSpecificPart());
	return UrlEncoding.encode(buf.toString(), Profile.SCHEMESPECIFICPART);
	}

	public String toASCIIString() {
	StringBuilder buf = new StringBuilder();
	String scheme = getScheme();
	if (scheme != null && scheme.length() != 0)
	buf.append(scheme)
	.append(':');
	buf.append(getASCIISchemeSpecificPart());
	return buf.toString();
	}

	public java.net.URI toURI() throws URISyntaxException {
	return new java.net.URI(toASCIIString());
	}

	public java.net.URL toURL() throws MalformedURLException, URISyntaxException {
	return toURI().toURL();
	}

	private void parseAuthority() {
	if (authority != null) {
	Matcher auth = AUTHORITYPATTERN.matcher(authority);
	if (auth.find()) {
	userinfo = auth.group(1);
	host = auth.group(2);
	if (auth.group(3) != null)
	port = Integer.parseInt(auth.group(3));
	else
	port = -1;
	}
	try {
	CharUtils.verify(userinfo, Profile.IUSERINFO);
	CharUtils.verify(host, Profile.IHOST);
	} catch (InvalidCharacterException e) {
	throw new IRISyntaxException(e);
	}
	}
	}

	private void parse(String iri) {
	try {
	Matcher irim = IRIPATTERN.matcher(iri);
	if (irim.find()) {
	String scheme = irim.group(1);
	_scheme = SchemeRegistry.get(scheme);
	authority = irim.group(2);
	path = irim.group(3);
	query = irim.group(4);
	fragment = irim.group(5);
	parseAuthority();
	try {
	CharUtils.verify(scheme, Profile.SCHEME);
	CharUtils.verify(path, Profile.IPATH);
	CharUtils.verify(query, Profile.IQUERY);
	CharUtils.verify(fragment, Profile.IFRAGMENT);
	} catch (InvalidCharacterException e) {
	throw new IRISyntaxException(e);
	}
	} else {
	throw new IRISyntaxException("Invalid Syntax");
	}
	} catch (IRISyntaxException e) {
	throw e;
	} catch (Exception e) {
	throw new IRISyntaxException(e);
	}
	}

	private static final Pattern IRIPATTERN =
	Pattern.compile("^(?:([^:/?#]+):)?(?://([^/?#]))?([^?#])(?:\\?([^#]))?(?:#(.))?");

	private static final Pattern AUTHORITYPATTERN =
	Pattern.compile("^(?:(.)?@)?((?:\\[.\\])\|(?:[^:]*))?(?::(\\d+))?");

	/**
	* Returns a new IRI with a trailing slash appended to the path, if necessary.
	* The query and fragment are omitted from the resulting IRI
	*/
	public IRI trailingSlash() {
	return this.resolve(path + "/");
	}

	}