server/src/main/java/org/apache/abdera/protocol/server/impl/TemplateTargetBuilder.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.security.Principal;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.regex.Pattern;

 import org.apache.abdera.i18n.templates.Context;
 import org.apache.abdera.i18n.templates.DelegatingContext;
 import org.apache.abdera.i18n.templates.HashMapContext;
 import org.apache.abdera.i18n.templates.ObjectContext;
 import org.apache.abdera.i18n.templates.Template;
 import org.apache.abdera.protocol.server.RequestContext;
 import org.apache.abdera.protocol.server.Target;
 import org.apache.abdera.protocol.server.TargetBuilder;
 import org.apache.abdera.protocol.server.RequestContext.Scope;

 /**
  * A TargetBuilder implementation that uses URI/IRI Templates to construct
  * URIs/IRIs.  The input parameter can be a java.util.Map<String,Object>,
  * an instance of the org.apache.abdera.i18n.templates.Context interface,
  * or any Java object with public getter methods.
  */
 @SuppressWarnings("unchecked")
 public class TemplateTargetBuilder
   implements TargetBuilder {

   protected final Map<Object,Template> templates
     = new HashMap<Object,Template>();

   public TemplateTargetBuilder() {}

   public TemplateTargetBuilder(Map<Object,Template> templates) {
     for (Map.Entry<Object, Template> entry : templates.entrySet()) {
       setTemplate(entry.getKey(),entry.getValue());
     }
   }

   public TemplateTargetBuilder setTemplate(Object key, String template) {
     return setTemplate(key, new Template(template));
   }

   public TemplateTargetBuilder setTemplate(Object key, Template template) {
     template = new Template(doReplacements(template.getPattern()));
     templates.put(key,template);
     return this;
   }

   private String doReplacements(String template) {
     for (Variable var : Variable.values()) {
       String rep = var.getReplacement();
       if (rep != null) {
         template = template.replaceAll("\\Q{" + var.name().toLowerCase() + "}\\E",rep);
       }
     }
     return template;
   }

   public static Context getContext(RequestContext request, Object param) {
     Context context = null;
     if (param != null) {
       if (param instanceof Map) {
         context = new HashMapContext((Map<String,Object>)param, true);
       } else if (param instanceof Context) {
         context = (Context)param;
       } else {
         context = new ObjectContext(param,true);
       }
     }
     return new TemplateContext(request, context);
   }

   public static <T>List<T> asList(Iterator<T> i) {
     List<T> list = new ArrayList<T>();
     while(i.hasNext())
       list.add(i.next());
     return list;
   }

   public String urlFor(
     RequestContext request,
     Object key,
     Object param) {
       Template template = templates.get(key);
       return template != null ? template.expand(getContext(request,param)) : null;
   }

   public static class TemplateContext
     extends DelegatingContext {

     private static final long serialVersionUID = 4332356546022014897L;

     private final RequestContext request;

     public TemplateContext(
       RequestContext request,
       Context subcontext) {
         super(subcontext);
         this.request = request;
     }

     private String[] split(String val) {
       if (val.equals("")) return null;
       String[] segments = val.split("/");
       return segments.length > 0 ? segments : null;
     }

     protected <T> T resolveActual(
       String var) {
         Variable variable = Variable.get(var);
         if (variable == null)
           return subcontext != null ? (T)subcontext.resolve(var) : null;
         switch(variable) {
           case REQUEST_URI:
             return (T) request.getUri().toString();
           case REQUEST_RESOLVED_URI:
             return (T) request.getResolvedUri().toString();
           case REQUEST_CONTENT_TYPE:
             return (T) request.getContentType().toString();
           case REQUEST_CONTEXT_PATH:
             return (T) split(request.getContextPath());
           case REQUEST_PARAMETER:
             String name = Variable.REQUEST_PARAMETER.label(var);
             return (T) request.getParameter(name);
           case REQUEST_LANGUAGE:
             return (T) request.getAcceptLanguage();
           case REQUEST_CHARSET:
             return (T) request.getAcceptCharset();
           case REQUEST_USER:
             Principal p = request.getPrincipal();
             return p != null ? (T)p.getName() : null;
           case SESSION_ATTRIBUTE:
             name = Variable.SESSION_ATTRIBUTE.label(var);
             return (T) request.getAttribute(Scope.SESSION, name);
           case REQUEST_ATTRIBUTE:
             name = Variable.REQUEST_ATTRIBUTE.label(var);
             return (T) request.getAttribute(Scope.REQUEST, name);
           case REQUEST_HEADER:
             name = Variable.REQUEST_HEADER.label(var);
             return (T) request.getHeader(name);
           case TARGET_PARAMETER:
             name = Variable.TARGET_PARAMETER.label(var);
             return (T) request.getTarget().getParameter(name);
           case TARGET_IDENTITY:
             return (T) request.getTarget().getIdentity();
           case TARGET_PATH:
             return (T) split(request.getTargetPath());
           case TARGET_BASE:
             return (T) split(request.getTargetBasePath());
           default:
             return subcontext != null ? (T)subcontext.resolve(var) : null;
         }
     }

     public Iterator<String> iterator() {
       List<String> vars = new ArrayList<String>();
       for (String var : subcontext)
         vars.add(var);
       for (String var : request.getParameterNames())
         vars.add(toVar(Variable.REQUEST_PARAMETER,var));
       for (String var : request.getAttributeNames(Scope.SESSION))
         vars.add(toVar(Variable.SESSION_ATTRIBUTE,var));
       for (String var : request.getAttributeNames(Scope.REQUEST))
         vars.add(toVar(Variable.REQUEST_ATTRIBUTE,var));
       for (String var : request.getHeaderNames())
         vars.add(toVar(Variable.REQUEST_HEADER, var));
       Target target = request.getTarget();
       for (String var : target.getParameterNames())
         vars.add(toVar(Variable.TARGET_PARAMETER, var));
       vars.add(Variable.REQUEST_CONTEXT_PATH.name().toLowerCase());
       vars.add(Variable.REQUEST_CONTENT_TYPE.name().toLowerCase());
       vars.add(Variable.REQUEST_URI.name().toLowerCase());
       vars.add(Variable.REQUEST_RESOLVED_URI.name().toLowerCase());
       vars.add(Variable.REQUEST_LANGUAGE.name().toLowerCase());
       vars.add(Variable.REQUEST_CHARSET.name().toLowerCase());
       vars.add(Variable.REQUEST_USER.name().toLowerCase());
       vars.add(Variable.TARGET_IDENTITY.name().toLowerCase());
       vars.add(Variable.TARGET_PATH.name().toLowerCase());
       vars.add(Variable.TARGET_BASE.name().toLowerCase());
       return vars.iterator();
     }
   }

   private static String toVar(Variable variable, String label) {
     return variable.name().toLowerCase() + "_" + label;
   }

   public static enum Variable {
     REQUEST_CONTEXT_PATH("{-opt|/|request_context_path}{-listjoin|/|request_context_path}"),
     REQUEST_CONTENT_TYPE,
     REQUEST_URI,
     REQUEST_RESOLVED_URI,
     REQUEST_PARAMETER,
     REQUEST_LANGUAGE,
     REQUEST_CHARSET,
     REQUEST_USER,
     SESSION_ATTRIBUTE,
     REQUEST_ATTRIBUTE,
     REQUEST_HEADER,
     TARGET_PARAMETER,
     TARGET_IDENTITY,
     TARGET_PATH("{-opt|/|target_path}{-listjoin|/|target_path}"),
     TARGET_BASE("{-opt|/|target_base}{-listjoin|/|target_base}"),
     ;

     static Variable get(String var) {
       if (REQUEST_PARAMETER.match(var)) {
         return REQUEST_PARAMETER;
       } else if (SESSION_ATTRIBUTE.match(var)) {
         return SESSION_ATTRIBUTE;
       } else if (REQUEST_ATTRIBUTE.match(var)) {
         return REQUEST_ATTRIBUTE;
       } else if (REQUEST_HEADER.match(var)) {
         return REQUEST_HEADER;
       } else if (TARGET_PARAMETER.match(var)) {
         return TARGET_PARAMETER;
       } else {
         try {
           return Variable.valueOf(var.toUpperCase());
         } catch (Exception e) {
           return null;
         }
       }
     }

     private final Pattern p;
     private final String replacement;

     Variable() {
       this(null);
     }

     Variable(String replacement) {
       this.p = Pattern.compile("\\Q" + name() + "_\\E.*", Pattern.CASE_INSENSITIVE);
       this.replacement = replacement;
     }

     String getReplacement() {
       return replacement;
     }

     boolean match(String var) {
       return p.matcher(var).matches();
     }

     String label(String var) {
       return var.substring(name().length() + 1);
     }
   }

 }
	/*
	* 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.security.Principal;
	import java.util.ArrayList;
	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.List;
	import java.util.Map;
	import java.util.regex.Pattern;

	import org.apache.abdera.i18n.templates.Context;
	import org.apache.abdera.i18n.templates.DelegatingContext;
	import org.apache.abdera.i18n.templates.HashMapContext;
	import org.apache.abdera.i18n.templates.ObjectContext;
	import org.apache.abdera.i18n.templates.Template;
	import org.apache.abdera.protocol.server.RequestContext;
	import org.apache.abdera.protocol.server.Target;
	import org.apache.abdera.protocol.server.TargetBuilder;
	import org.apache.abdera.protocol.server.RequestContext.Scope;

	/**
	* A TargetBuilder implementation that uses URI/IRI Templates to construct
	* URIs/IRIs. The input parameter can be a java.util.Map<String,Object>,
	* an instance of the org.apache.abdera.i18n.templates.Context interface,
	* or any Java object with public getter methods.
	*/
	@SuppressWarnings("unchecked")
	public class TemplateTargetBuilder
	implements TargetBuilder {

	protected final Map<Object,Template> templates
	= new HashMap<Object,Template>();

	public TemplateTargetBuilder() {}

	public TemplateTargetBuilder(Map<Object,Template> templates) {
	for (Map.Entry<Object, Template> entry : templates.entrySet()) {
	setTemplate(entry.getKey(),entry.getValue());
	}
	}

	public TemplateTargetBuilder setTemplate(Object key, String template) {
	return setTemplate(key, new Template(template));
	}

	public TemplateTargetBuilder setTemplate(Object key, Template template) {
	template = new Template(doReplacements(template.getPattern()));
	templates.put(key,template);
	return this;
	}

	private String doReplacements(String template) {
	for (Variable var : Variable.values()) {
	String rep = var.getReplacement();
	if (rep != null) {
	template = template.replaceAll("\\Q{" + var.name().toLowerCase() + "}\\E",rep);
	}
	}
	return template;
	}

	public static Context getContext(RequestContext request, Object param) {
	Context context = null;
	if (param != null) {
	if (param instanceof Map) {
	context = new HashMapContext((Map<String,Object>)param, true);
	} else if (param instanceof Context) {
	context = (Context)param;
	} else {
	context = new ObjectContext(param,true);
	}
	}
	return new TemplateContext(request, context);
	}

	public static <T>List<T> asList(Iterator<T> i) {
	List<T> list = new ArrayList<T>();
	while(i.hasNext())
	list.add(i.next());
	return list;
	}

	public String urlFor(
	RequestContext request,
	Object key,
	Object param) {
	Template template = templates.get(key);
	return template != null ? template.expand(getContext(request,param)) : null;
	}

	public static class TemplateContext
	extends DelegatingContext {

	private static final long serialVersionUID = 4332356546022014897L;

	private final RequestContext request;

	public TemplateContext(
	RequestContext request,
	Context subcontext) {
	super(subcontext);
	this.request = request;
	}

	private String[] split(String val) {
	if (val.equals("")) return null;
	String[] segments = val.split("/");
	return segments.length > 0 ? segments : null;
	}

	protected <T> T resolveActual(
	String var) {
	Variable variable = Variable.get(var);
	if (variable == null)
	return subcontext != null ? (T)subcontext.resolve(var) : null;
	switch(variable) {
	case REQUEST_URI:
	return (T) request.getUri().toString();
	case REQUEST_RESOLVED_URI:
	return (T) request.getResolvedUri().toString();
	case REQUEST_CONTENT_TYPE:
	return (T) request.getContentType().toString();
	case REQUEST_CONTEXT_PATH:
	return (T) split(request.getContextPath());
	case REQUEST_PARAMETER:
	String name = Variable.REQUEST_PARAMETER.label(var);
	return (T) request.getParameter(name);
	case REQUEST_LANGUAGE:
	return (T) request.getAcceptLanguage();
	case REQUEST_CHARSET:
	return (T) request.getAcceptCharset();
	case REQUEST_USER:
	Principal p = request.getPrincipal();
	return p != null ? (T)p.getName() : null;
	case SESSION_ATTRIBUTE:
	name = Variable.SESSION_ATTRIBUTE.label(var);
	return (T) request.getAttribute(Scope.SESSION, name);
	case REQUEST_ATTRIBUTE:
	name = Variable.REQUEST_ATTRIBUTE.label(var);
	return (T) request.getAttribute(Scope.REQUEST, name);
	case REQUEST_HEADER:
	name = Variable.REQUEST_HEADER.label(var);
	return (T) request.getHeader(name);
	case TARGET_PARAMETER:
	name = Variable.TARGET_PARAMETER.label(var);
	return (T) request.getTarget().getParameter(name);
	case TARGET_IDENTITY:
	return (T) request.getTarget().getIdentity();
	case TARGET_PATH:
	return (T) split(request.getTargetPath());
	case TARGET_BASE:
	return (T) split(request.getTargetBasePath());
	default:
	return subcontext != null ? (T)subcontext.resolve(var) : null;
	}
	}

	public Iterator<String> iterator() {
	List<String> vars = new ArrayList<String>();
	for (String var : subcontext)
	vars.add(var);
	for (String var : request.getParameterNames())
	vars.add(toVar(Variable.REQUEST_PARAMETER,var));
	for (String var : request.getAttributeNames(Scope.SESSION))
	vars.add(toVar(Variable.SESSION_ATTRIBUTE,var));
	for (String var : request.getAttributeNames(Scope.REQUEST))
	vars.add(toVar(Variable.REQUEST_ATTRIBUTE,var));
	for (String var : request.getHeaderNames())
	vars.add(toVar(Variable.REQUEST_HEADER, var));
	Target target = request.getTarget();
	for (String var : target.getParameterNames())
	vars.add(toVar(Variable.TARGET_PARAMETER, var));
	vars.add(Variable.REQUEST_CONTEXT_PATH.name().toLowerCase());
	vars.add(Variable.REQUEST_CONTENT_TYPE.name().toLowerCase());
	vars.add(Variable.REQUEST_URI.name().toLowerCase());
	vars.add(Variable.REQUEST_RESOLVED_URI.name().toLowerCase());
	vars.add(Variable.REQUEST_LANGUAGE.name().toLowerCase());
	vars.add(Variable.REQUEST_CHARSET.name().toLowerCase());
	vars.add(Variable.REQUEST_USER.name().toLowerCase());
	vars.add(Variable.TARGET_IDENTITY.name().toLowerCase());
	vars.add(Variable.TARGET_PATH.name().toLowerCase());
	vars.add(Variable.TARGET_BASE.name().toLowerCase());
	return vars.iterator();
	}
	}

	private static String toVar(Variable variable, String label) {
	return variable.name().toLowerCase() + "_" + label;
	}

	public static enum Variable {
	REQUEST_CONTEXT_PATH("{-opt\|/\|request_context_path}{-listjoin\|/\|request_context_path}"),
	REQUEST_CONTENT_TYPE,
	REQUEST_URI,
	REQUEST_RESOLVED_URI,
	REQUEST_PARAMETER,
	REQUEST_LANGUAGE,
	REQUEST_CHARSET,
	REQUEST_USER,
	SESSION_ATTRIBUTE,
	REQUEST_ATTRIBUTE,
	REQUEST_HEADER,
	TARGET_PARAMETER,
	TARGET_IDENTITY,
	TARGET_PATH("{-opt\|/\|target_path}{-listjoin\|/\|target_path}"),
	TARGET_BASE("{-opt\|/\|target_base}{-listjoin\|/\|target_base}"),
	;

	static Variable get(String var) {
	if (REQUEST_PARAMETER.match(var)) {
	return REQUEST_PARAMETER;
	} else if (SESSION_ATTRIBUTE.match(var)) {
	return SESSION_ATTRIBUTE;
	} else if (REQUEST_ATTRIBUTE.match(var)) {
	return REQUEST_ATTRIBUTE;
	} else if (REQUEST_HEADER.match(var)) {
	return REQUEST_HEADER;
	} else if (TARGET_PARAMETER.match(var)) {
	return TARGET_PARAMETER;
	} else {
	try {
	return Variable.valueOf(var.toUpperCase());
	} catch (Exception e) {
	return null;
	}
	}
	}

	private final Pattern p;
	private final String replacement;

	Variable() {
	this(null);
	}

	Variable(String replacement) {
	this.p = Pattern.compile("\\Q" + name() + "_\\E.*", Pattern.CASE_INSENSITIVE);
	this.replacement = replacement;
	}

	String getReplacement() {
	return replacement;
	}

	boolean match(String var) {
	return p.matcher(var).matches();
	}

	String label(String var) {
	return var.substring(name().length() + 1);
	}
	}

	}