server/src/main/java/org/apache/abdera/protocol/server/impl/RegexTargetResolver.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.abdera.protocol.server.impl;

 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 import org.apache.abdera.protocol.Request;
 import org.apache.abdera.protocol.Resolver;
 import org.apache.abdera.protocol.server.RequestContext;
 import org.apache.abdera.protocol.server.Target;
 import org.apache.abdera.protocol.server.TargetType;

 /**
  * <p>Provides a utility class helpful for determining which type of resource
  * the client is requesting.  Each resource type (e.g. service doc, collection,
  * entry, edit uri, media resource, etc) is assigned a regex pattern.  Given
  * the request URI (path and querystring), this will determine which resource
  * was selected and return an appropriate TargetMatcher.  TargetMatcher is
  * essentially just a simplified version of the java.util.regex.Matcher that
  * also specifies the Resource Type.</p>
  *
  * <pre>
  *  RequestContext request = ...
  *  RegexTargetResolver tr = new RegexTargetResolver();
  *  tr.setPattern("/atom",ResourceType.INTROSPECTION)
  *    .setPattern("/atom/([^/#?]+)",ResourceType.COLLECTION)
  *    .setPattern("/atom/([^/#?]+)/([^/#?]+)",ResourceType.ENTRY)
  *    .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?edit",ResourceType.ENTRY_EDIT)
  *    .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?media",ResourceType.MEDIA)
  *    .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?edit-media",ResourceType.MEDIA_EDIT);
  *
  *  Target target = tr.resolve(request);
  *  System.out.println(target.getType());
  *  System.out.println(targer.getParameter("foo"));
  * </pre>
  *
  */
 public class RegexTargetResolver
   implements Resolver<Target> {

   protected final Map<Pattern, TargetType> patterns;
   protected final Map<Pattern, String[]> fields;

   public RegexTargetResolver() {
     this.patterns = new HashMap<Pattern, TargetType>();
     this.fields = new HashMap<Pattern, String[]>();
   }

   public RegexTargetResolver(Map<String, TargetType> patterns) {
     this.patterns = new HashMap<Pattern, TargetType>();
     this.fields = new HashMap<Pattern, String[]>();
     for (String p : patterns.keySet()) {
       TargetType type = patterns.get(p);
       setPattern(p,type);
     }
   }

   public RegexTargetResolver setPattern(
     String pattern,
     TargetType type) {
       return setPattern(pattern,type, new String[0]);
   }

   public RegexTargetResolver setPattern(
     String pattern,
     TargetType type,
     String... fields) {
       Pattern p = Pattern.compile(pattern);
       this.patterns.put(p,type);
       this.fields.put(p,fields);
       return this;
   }

   public Target resolve(Request request) {
     RequestContext context = (RequestContext) request;
     String uri = context.getTargetPath();
     for (Pattern pattern : patterns.keySet()) {
       Matcher matcher = pattern.matcher(uri);
       if (matcher.matches()) {
         TargetType type = this.patterns.get(pattern);
         String[] fields = this.fields.get(pattern);
         return getTarget(type, context, matcher, fields);
       }
     }
     return null;
   }

   protected Target getTarget(
     TargetType type,
     RequestContext request,
     Matcher matcher,
     String[] fields) {
       return new RegexTarget(type, request, matcher, fields);
   }

   public String toString() {
     StringBuilder buf = new StringBuilder();
     buf.append("Regex Target Resolver:\n");
     for (Pattern pattern : patterns.keySet()) {
       TargetType type = this.patterns.get(pattern);
       String[] fields = this.fields.get(pattern);
       buf.append(pattern.toString() + ", Type: " + type + ", Fields: " + Arrays.toString(fields));
     }
     return buf.toString();
   }

   public int hashCode() {
     final int prime = 31;
     int result = 1;
     result = prime * result + ((fields == null) ? 0 : fields.hashCode());
     result = prime * result + ((patterns == null) ? 0 : patterns.hashCode());
     return result;
   }

   public boolean equals(Object obj) {
     if (this == obj) return true;
     if (obj == null) return false;
     if (getClass() != obj.getClass()) return false;
     final RegexTargetResolver other = (RegexTargetResolver) obj;
     if (fields == null) {
       if (other.fields != null) return false;
     } else if (!fields.equals(other.fields)) return false;
     if (patterns == null) {
       if (other.patterns != null) return false;
     } else if (!patterns.equals(other.patterns)) return false;
     return true;
   }

   public static class RegexTarget
     extends SimpleTarget
     implements Target {

     private static final long serialVersionUID = 165211244926064449L;
     protected Matcher matcher;
     protected String[] fields;

     public RegexTarget(
       TargetType type,
       RequestContext context,
       Matcher matcher,
       String[] fields) {
         super(type, context);
         this.matcher = matcher;
         this.fields = fields;
     }

     public String getParameter(String name) {
       if (fields == null) return super.getParameter(name);
       int idx = 0;
       for (int n = 0; n < fields.length; n++)
         if (fields[n].equalsIgnoreCase(name)) idx = n + 1;
       return idx > 0 && idx <= matcher.groupCount() ?
         matcher.group(idx) : super.getParameter(name);
     }

     public String[] getParameterNames() {
       String[] names = super.getParameterNames();
       List<String> list = new ArrayList<String>();
       if (names != null) list.addAll(Arrays.asList(names));
       if (fields != null) list.addAll(Arrays.asList(fields));
       return list.toArray(new String[list.size()]);
     }

     @Override
     public int hashCode() {
       final int PRIME = 31;
       int result = 1;
       String m = matcher.group(0);
       String p = matcher.pattern().pattern();
       result = PRIME * result + super.hashCode();
       result = PRIME * result + ((m == null) ? 0 : m.hashCode());
       result = PRIME * result + ((p == null) ? 0 : p.hashCode());
       result = PRIME * result + ((type == null) ? 0 : type.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 RegexTarget other = (RegexTarget) obj;
       String m = matcher.group(0);
       String p = matcher.pattern().pattern();
       String m2 = other.matcher.group(0);
       String p2 = other.matcher.pattern().pattern();
       if (!super.equals(obj)) return false;
       if (m == null) {
         if (m2 != null)
           return false;
       } else if (!m.equals(m2))
         return false;
       if (p == null) {
         if (p2 != null)
           return false;
       } else if (!p.equals(p2))
         return false;
       if (type == null) {
         if (other.type != null)
           return false;
       } else if (!type.equals(other.type))
         return false;
       return true;
     }

     public String toString() {
       String m = matcher.group(0);
       String p = matcher.pattern().pattern();
       StringBuilder buf = new StringBuilder();
       buf.append("RegexTarget[")
          .append(p)
          .append(" ==> ")
          .append(m)
          .append("] = ")
          .append(type.toString())
          .append("\n");
       String[] params = getParameterNames();
       for (String param : params) {
         buf.append("    ")
            .append(param)
            .append(" = ")
            .append(getParameter(param))
            .append("\n");
       }
       return buf.toString();
     }

     public String getIdentity() {
       return context.getUri().toString();
     }

   }

 }
	/*
	* 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.abdera.protocol.server.impl;

	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.HashMap;
	import java.util.List;
	import java.util.Map;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;

	import org.apache.abdera.protocol.Request;
	import org.apache.abdera.protocol.Resolver;
	import org.apache.abdera.protocol.server.RequestContext;
	import org.apache.abdera.protocol.server.Target;
	import org.apache.abdera.protocol.server.TargetType;

	/**
	* <p>Provides a utility class helpful for determining which type of resource
	* the client is requesting. Each resource type (e.g. service doc, collection,
	* entry, edit uri, media resource, etc) is assigned a regex pattern. Given
	* the request URI (path and querystring), this will determine which resource
	* was selected and return an appropriate TargetMatcher. TargetMatcher is
	* essentially just a simplified version of the java.util.regex.Matcher that
	* also specifies the Resource Type.</p>
	*
	* <pre>
	* RequestContext request = ...
	* RegexTargetResolver tr = new RegexTargetResolver();
	* tr.setPattern("/atom",ResourceType.INTROSPECTION)
	* .setPattern("/atom/([^/#?]+)",ResourceType.COLLECTION)
	* .setPattern("/atom/([^/#?]+)/([^/#?]+)",ResourceType.ENTRY)
	* .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?edit",ResourceType.ENTRY_EDIT)
	* .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?media",ResourceType.MEDIA)
	* .setPattern("/atom/([^/#?]+)/([^/#?]+)\\?edit-media",ResourceType.MEDIA_EDIT);
	*
	* Target target = tr.resolve(request);
	* System.out.println(target.getType());
	* System.out.println(targer.getParameter("foo"));
	* </pre>
	*
	*/
	public class RegexTargetResolver
	implements Resolver<Target> {

	protected final Map<Pattern, TargetType> patterns;
	protected final Map<Pattern, String[]> fields;

	public RegexTargetResolver() {
	this.patterns = new HashMap<Pattern, TargetType>();
	this.fields = new HashMap<Pattern, String[]>();
	}

	public RegexTargetResolver(Map<String, TargetType> patterns) {
	this.patterns = new HashMap<Pattern, TargetType>();
	this.fields = new HashMap<Pattern, String[]>();
	for (String p : patterns.keySet()) {
	TargetType type = patterns.get(p);
	setPattern(p,type);
	}
	}

	public RegexTargetResolver setPattern(
	String pattern,
	TargetType type) {
	return setPattern(pattern,type, new String[0]);
	}

	public RegexTargetResolver setPattern(
	String pattern,
	TargetType type,
	String... fields) {
	Pattern p = Pattern.compile(pattern);
	this.patterns.put(p,type);
	this.fields.put(p,fields);
	return this;
	}

	public Target resolve(Request request) {
	RequestContext context = (RequestContext) request;
	String uri = context.getTargetPath();
	for (Pattern pattern : patterns.keySet()) {
	Matcher matcher = pattern.matcher(uri);
	if (matcher.matches()) {
	TargetType type = this.patterns.get(pattern);
	String[] fields = this.fields.get(pattern);
	return getTarget(type, context, matcher, fields);
	}
	}
	return null;
	}

	protected Target getTarget(
	TargetType type,
	RequestContext request,
	Matcher matcher,
	String[] fields) {
	return new RegexTarget(type, request, matcher, fields);
	}

	public String toString() {
	StringBuilder buf = new StringBuilder();
	buf.append("Regex Target Resolver:\n");
	for (Pattern pattern : patterns.keySet()) {
	TargetType type = this.patterns.get(pattern);
	String[] fields = this.fields.get(pattern);
	buf.append(pattern.toString() + ", Type: " + type + ", Fields: " + Arrays.toString(fields));
	}
	return buf.toString();
	}

	public int hashCode() {
	final int prime = 31;
	int result = 1;
	result = prime * result + ((fields == null) ? 0 : fields.hashCode());
	result = prime * result + ((patterns == null) ? 0 : patterns.hashCode());
	return result;
	}

	public boolean equals(Object obj) {
	if (this == obj) return true;
	if (obj == null) return false;
	if (getClass() != obj.getClass()) return false;
	final RegexTargetResolver other = (RegexTargetResolver) obj;
	if (fields == null) {
	if (other.fields != null) return false;
	} else if (!fields.equals(other.fields)) return false;
	if (patterns == null) {
	if (other.patterns != null) return false;
	} else if (!patterns.equals(other.patterns)) return false;
	return true;
	}

	public static class RegexTarget
	extends SimpleTarget
	implements Target {

	private static final long serialVersionUID = 165211244926064449L;
	protected Matcher matcher;
	protected String[] fields;

	public RegexTarget(
	TargetType type,
	RequestContext context,
	Matcher matcher,
	String[] fields) {
	super(type, context);
	this.matcher = matcher;
	this.fields = fields;
	}

	public String getParameter(String name) {
	if (fields == null) return super.getParameter(name);
	int idx = 0;
	for (int n = 0; n < fields.length; n++)
	if (fields[n].equalsIgnoreCase(name)) idx = n + 1;
	return idx > 0 && idx <= matcher.groupCount() ?
	matcher.group(idx) : super.getParameter(name);
	}

	public String[] getParameterNames() {
	String[] names = super.getParameterNames();
	List<String> list = new ArrayList<String>();
	if (names != null) list.addAll(Arrays.asList(names));
	if (fields != null) list.addAll(Arrays.asList(fields));
	return list.toArray(new String[list.size()]);
	}

	@Override
	public int hashCode() {
	final int PRIME = 31;
	int result = 1;
	String m = matcher.group(0);
	String p = matcher.pattern().pattern();
	result = PRIME * result + super.hashCode();
	result = PRIME * result + ((m == null) ? 0 : m.hashCode());
	result = PRIME * result + ((p == null) ? 0 : p.hashCode());
	result = PRIME * result + ((type == null) ? 0 : type.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 RegexTarget other = (RegexTarget) obj;
	String m = matcher.group(0);
	String p = matcher.pattern().pattern();
	String m2 = other.matcher.group(0);
	String p2 = other.matcher.pattern().pattern();
	if (!super.equals(obj)) return false;
	if (m == null) {
	if (m2 != null)
	return false;
	} else if (!m.equals(m2))
	return false;
	if (p == null) {
	if (p2 != null)
	return false;
	} else if (!p.equals(p2))
	return false;
	if (type == null) {
	if (other.type != null)
	return false;
	} else if (!type.equals(other.type))
	return false;
	return true;
	}

	public String toString() {
	String m = matcher.group(0);
	String p = matcher.pattern().pattern();
	StringBuilder buf = new StringBuilder();
	buf.append("RegexTarget[")
	.append(p)
	.append(" ==> ")
	.append(m)
	.append("] = ")
	.append(type.toString())
	.append("\n");
	String[] params = getParameterNames();
	for (String param : params) {
	buf.append(" ")
	.append(param)
	.append(" = ")
	.append(getParameter(param))
	.append("\n");
	}
	return buf.toString();
	}

	public String getIdentity() {
	return context.getUri().toString();
	}

	}

	}