dev/core/src/com/google/gwt/dev/ServletValidator.java - gwt - Git at Google

 /*
  * Copyright 2009 Google Inc.
  *
  * Licensed 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.
  */
 package com.google.gwt.dev;

 import com.google.gwt.core.ext.TreeLogger;
 import com.google.gwt.dev.util.collect.HashSet;

 import org.xml.sax.Attributes;
 import org.xml.sax.SAXException;
 import org.xml.sax.helpers.DefaultHandler;

 import java.io.File;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Set;
 import java.util.Stack;

 import javax.xml.parsers.SAXParser;
 import javax.xml.parsers.SAXParserFactory;

 /**
  * Validates that <code>&lt;servlet&gt;</code> tags in a GWT module match ones
  * from a <code>WEB-INF/web.xml</code>.
  */
 class ServletValidator {

   /**
    * Collect servlet information from a web xml.
    */
   private static final class WebXmlDataCollector extends DefaultHandler {
     /*
      * TODO(scottb): this should have been implemented as a Schema.
      */

     private static class ElementStack {
       private final Stack<String> stack = new Stack<String>();

       public boolean exactly(String elementName, int depth) {
         return (depth == stack.size() - 1)
             && elementName.equals(stack.get(depth));
       }

       public String peek() {
         return stack.peek();
       }

       public String pop() {
         return stack.pop();
       }

       public void push(String elementName) {
         stack.push(elementName);
       }

       public boolean within(String elementName, int depth) {
         return (depth < stack.size()) && elementName.equals(stack.get(depth));
       }
     }

     private Set<String> accumulateClasses = new HashSet<String>();
     private Set<String> accumulatePaths = new HashSet<String>();
     private final TreeLogger branch;
     private final Stack<StringBuilder> cdataStack = new Stack<StringBuilder>();
     private final Map<String, String> classNameToServletName;
     private final ElementStack context = new ElementStack();
     private String currentServletName;
     private String indent = "";
     private final Map<String, Set<String>> servletNameToPaths;

     private WebXmlDataCollector(TreeLogger branch,
         Map<String, String> classNameToServletName,
         Map<String, Set<String>> servletNameToPaths) {
       this.branch = branch;
       this.classNameToServletName = classNameToServletName;
       this.servletNameToPaths = servletNameToPaths;
     }

     @Override
     public void characters(char[] ch, int start, int length)
         throws SAXException {
       cdataStack.peek().append(ch, start, length);
     }

     @Override
     public void endElement(String uri, String localName, String qName)
         throws SAXException {
       String cdata = cdataStack.pop().toString().trim();
       if (context.within("web-app", 0)) {
         if (context.within("servlet", 1)) {
           if (context.exactly("servlet-name", 2)) {
             currentServletName = cdata;
           } else if (context.exactly("servlet-class", 2)) {
             accumulateClasses.add(cdata);
           } else if (context.exactly("servlet", 1)) {
             if (currentServletName != null) {
               for (String className : accumulateClasses) {
                 classNameToServletName.put(className, currentServletName);
               }
               currentServletName = null;
             }
             accumulateClasses.clear();
           }
         } else if (context.within("servlet-mapping", 1)) {
           if (context.exactly("servlet-name", 2)) {
             currentServletName = cdata;
           } else if (context.exactly("url-pattern", 2)) {
             accumulatePaths.add(cdata);
           } else if (context.exactly("servlet-mapping", 1)) {
             if (currentServletName != null) {
               Set<String> servletPaths = servletNameToPaths.get(currentServletName);
               if (servletPaths == null) {
                 servletPaths = new HashSet<String>();
                 servletNameToPaths.put(currentServletName, servletPaths);
               }
               servletPaths.addAll(accumulatePaths);
             }
             currentServletName = null;
             accumulatePaths.clear();
           }
         }
       }

       assert qName.equals(context.peek());
       context.pop();

       if (cdata.length() > 0) {
         if (branch.isLoggable(TreeLogger.DEBUG)) {
           branch.log(TreeLogger.DEBUG, "  characters: " + indent + cdata);
         }
       }
       indent = indent.substring(2);
       if (branch.isLoggable(TreeLogger.DEBUG)) {
         branch.log(TreeLogger.DEBUG, "  endElement: " + indent + qName);
       }
     }

     @Override
     public void startElement(String uri, String localName, String qName,
         Attributes attributes) throws SAXException {
       context.push(qName);
       cdataStack.push(new StringBuilder());

       StringBuilder sb = new StringBuilder();
       for (int i = 0; i < attributes.getLength(); ++i) {
         sb.append(' ');
         sb.append(attributes.getQName(i));
         sb.append("=\"");
         sb.append(attributes.getValue(i));
         sb.append('"');
       }
       if (branch.isLoggable(TreeLogger.DEBUG)) {
         branch.log(TreeLogger.DEBUG, "startElement: " + indent + qName
             + sb.toString());
       }
       indent += "  ";
     }
   }

   public static ServletValidator create(TreeLogger logger, File webXml) {
     try {
       return create(logger, webXml.toURI().toURL());
     } catch (MalformedURLException e) {
       logger.log(TreeLogger.WARN, "Unable to process '"
           + webXml.getAbsolutePath() + "' for servlet validation", e);
       return null;
     }
   }

   public static ServletValidator create(TreeLogger logger, URL webXmlUrl) {
     String webXmlUrlString = webXmlUrl.toExternalForm();
     try {
       final TreeLogger branch = logger.branch(TreeLogger.DEBUG, "Parsing "
           + webXmlUrlString);
       SAXParserFactory fac = SAXParserFactory.newInstance();
       fac.setValidating(false);
       fac.setNamespaceAware(false);
       fac.setFeature(
           "http://apache.org/xml/features/nonvalidating/load-external-dtd",
           false);
       SAXParser parser = fac.newSAXParser();
       parser.getXMLReader().setFeature(
           "http://xml.org/sax/features/validation", false);
       parser.getXMLReader().setFeature(
           "http://xml.org/sax/features/namespaces", false);
       parser.getXMLReader().setFeature(
           "http://xml.org/sax/features/namespace-prefixes", false);

       Map<String, String> classNameToServletName = new HashMap<String, String>();
       Map<String, Set<String>> servletNameToPaths = new HashMap<String, Set<String>>();
       parser.parse(webXmlUrlString, new WebXmlDataCollector(branch,
           classNameToServletName, servletNameToPaths));

       Map<String, Set<String>> classNameToPaths = new HashMap<String, Set<String>>();
       for (Entry<String, String> entry : classNameToServletName.entrySet()) {
         classNameToPaths.put(entry.getKey(),
             servletNameToPaths.get(entry.getValue()));
       }
       return new ServletValidator(classNameToServletName, classNameToPaths);
     } catch (Exception e) {
       logger.log(TreeLogger.WARN, "Unable to process '" + webXmlUrlString
           + "' for servlet validation", e);
       return null;
     }
   }

   static String generateMissingMappingMessage(String servletClass,
       String servletPath, String servletName) {
     return "Module declares a servlet class '"
         + servletClass
         + "' with a mapping to '"
         + servletPath
         + "', but the web.xml has no corresponding mapping; please add the following lines to your web.xml:\n"
         + ServletWriter.generateServletMappingTag(servletName, servletPath);
   }

   static String generateMissingServletMessage(String servletClass,
       String servletPath) {
     String servletName = suggestServletName(servletClass);
     return "Module declares a servlet class '"
         + servletClass
         + "', but the web.xml has no corresponding declaration; please add the following lines to your web.xml:\n"
         + ServletWriter.generateServletTag(servletName, servletClass) + "\n"
         + ServletWriter.generateServletMappingTag(servletName, servletPath);
   }

   static String suggestServletName(String servletClass) {
     int pos = servletClass.lastIndexOf('.');
     String suggest = (pos < 0) ? servletClass : servletClass.substring(pos + 1);
     String firstChar = suggest.substring(0, 1).toLowerCase(Locale.ROOT);
     suggest = firstChar + suggest.substring(1);
     return suggest;
   }

   private final Map<String, Set<String>> classNameToPaths;

   private final Map<String, String> classNameToServletName;

   private ServletValidator(Map<String, String> classNameToServletName,
       Map<String, Set<String>> classNameToPaths) {
     this.classNameToServletName = classNameToServletName;
     this.classNameToPaths = classNameToPaths;
   }

   public void validate(TreeLogger logger, String servletClass,
       String servletPath) {
     if (containsServletClass(servletClass)) {
       if (!containsServletMapping(servletClass, servletPath)) {
         String servletName = getNameForClass(servletClass);
         assert (servletName != null);
         logger.log(TreeLogger.WARN, generateMissingMappingMessage(servletClass,
             servletPath, servletName));
       }
     } else {
       logger.log(TreeLogger.WARN, generateMissingServletMessage(servletClass,
           servletPath));
     }
   }

   boolean containsServletClass(String servletClass) {
     return classNameToServletName.get(servletClass) != null;
   }

   boolean containsServletMapping(String servletClass, String servletPath) {
     Set<String> paths = classNameToPaths.get(servletClass);
     return (paths != null) && paths.contains(servletPath);
   }

   String getNameForClass(String servletClass) {
     return classNameToServletName.get(servletClass);
   }
 }
	/*
	* Copyright 2009 Google Inc.
	*
	* Licensed 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.
	*/
	package com.google.gwt.dev;

	import com.google.gwt.core.ext.TreeLogger;
	import com.google.gwt.dev.util.collect.HashSet;

	import org.xml.sax.Attributes;
	import org.xml.sax.SAXException;
	import org.xml.sax.helpers.DefaultHandler;

	import java.io.File;
	import java.net.MalformedURLException;
	import java.net.URL;
	import java.util.HashMap;
	import java.util.Locale;
	import java.util.Map;
	import java.util.Map.Entry;
	import java.util.Set;
	import java.util.Stack;

	import javax.xml.parsers.SAXParser;
	import javax.xml.parsers.SAXParserFactory;

	/**
	* Validates that <code><servlet></code> tags in a GWT module match ones
	* from a <code>WEB-INF/web.xml</code>.
	*/
	class ServletValidator {

	/**
	* Collect servlet information from a web xml.
	*/
	private static final class WebXmlDataCollector extends DefaultHandler {
	/*
	* TODO(scottb): this should have been implemented as a Schema.
	*/

	private static class ElementStack {
	private final Stack<String> stack = new Stack<String>();

	public boolean exactly(String elementName, int depth) {
	return (depth == stack.size() - 1)
	&& elementName.equals(stack.get(depth));
	}

	public String peek() {
	return stack.peek();
	}

	public String pop() {
	return stack.pop();
	}

	public void push(String elementName) {
	stack.push(elementName);
	}

	public boolean within(String elementName, int depth) {
	return (depth < stack.size()) && elementName.equals(stack.get(depth));
	}
	}

	private Set<String> accumulateClasses = new HashSet<String>();
	private Set<String> accumulatePaths = new HashSet<String>();
	private final TreeLogger branch;
	private final Stack<StringBuilder> cdataStack = new Stack<StringBuilder>();
	private final Map<String, String> classNameToServletName;
	private final ElementStack context = new ElementStack();
	private String currentServletName;
	private String indent = "";
	private final Map<String, Set<String>> servletNameToPaths;

	private WebXmlDataCollector(TreeLogger branch,
	Map<String, String> classNameToServletName,
	Map<String, Set<String>> servletNameToPaths) {
	this.branch = branch;
	this.classNameToServletName = classNameToServletName;
	this.servletNameToPaths = servletNameToPaths;
	}

	@Override
	public void characters(char[] ch, int start, int length)
	throws SAXException {
	cdataStack.peek().append(ch, start, length);
	}

	@Override
	public void endElement(String uri, String localName, String qName)
	throws SAXException {
	String cdata = cdataStack.pop().toString().trim();
	if (context.within("web-app", 0)) {
	if (context.within("servlet", 1)) {
	if (context.exactly("servlet-name", 2)) {
	currentServletName = cdata;
	} else if (context.exactly("servlet-class", 2)) {
	accumulateClasses.add(cdata);
	} else if (context.exactly("servlet", 1)) {
	if (currentServletName != null) {
	for (String className : accumulateClasses) {
	classNameToServletName.put(className, currentServletName);
	}
	currentServletName = null;
	}
	accumulateClasses.clear();
	}
	} else if (context.within("servlet-mapping", 1)) {
	if (context.exactly("servlet-name", 2)) {
	currentServletName = cdata;
	} else if (context.exactly("url-pattern", 2)) {
	accumulatePaths.add(cdata);
	} else if (context.exactly("servlet-mapping", 1)) {
	if (currentServletName != null) {
	Set<String> servletPaths = servletNameToPaths.get(currentServletName);
	if (servletPaths == null) {
	servletPaths = new HashSet<String>();
	servletNameToPaths.put(currentServletName, servletPaths);
	}
	servletPaths.addAll(accumulatePaths);
	}
	currentServletName = null;
	accumulatePaths.clear();
	}
	}
	}

	assert qName.equals(context.peek());
	context.pop();

	if (cdata.length() > 0) {
	if (branch.isLoggable(TreeLogger.DEBUG)) {
	branch.log(TreeLogger.DEBUG, " characters: " + indent + cdata);
	}
	}
	indent = indent.substring(2);
	if (branch.isLoggable(TreeLogger.DEBUG)) {
	branch.log(TreeLogger.DEBUG, " endElement: " + indent + qName);
	}
	}

	@Override
	public void startElement(String uri, String localName, String qName,
	Attributes attributes) throws SAXException {
	context.push(qName);
	cdataStack.push(new StringBuilder());

	StringBuilder sb = new StringBuilder();
	for (int i = 0; i < attributes.getLength(); ++i) {
	sb.append(' ');
	sb.append(attributes.getQName(i));
	sb.append("=\"");
	sb.append(attributes.getValue(i));
	sb.append('"');
	}
	if (branch.isLoggable(TreeLogger.DEBUG)) {
	branch.log(TreeLogger.DEBUG, "startElement: " + indent + qName
	+ sb.toString());
	}
	indent += " ";
	}
	}

	public static ServletValidator create(TreeLogger logger, File webXml) {
	try {
	return create(logger, webXml.toURI().toURL());
	} catch (MalformedURLException e) {
	logger.log(TreeLogger.WARN, "Unable to process '"
	+ webXml.getAbsolutePath() + "' for servlet validation", e);
	return null;
	}
	}

	public static ServletValidator create(TreeLogger logger, URL webXmlUrl) {
	String webXmlUrlString = webXmlUrl.toExternalForm();
	try {
	final TreeLogger branch = logger.branch(TreeLogger.DEBUG, "Parsing "
	+ webXmlUrlString);
	SAXParserFactory fac = SAXParserFactory.newInstance();
	fac.setValidating(false);
	fac.setNamespaceAware(false);
	fac.setFeature(
	"http://apache.org/xml/features/nonvalidating/load-external-dtd",
	false);
	SAXParser parser = fac.newSAXParser();
	parser.getXMLReader().setFeature(
	"http://xml.org/sax/features/validation", false);
	parser.getXMLReader().setFeature(
	"http://xml.org/sax/features/namespaces", false);
	parser.getXMLReader().setFeature(
	"http://xml.org/sax/features/namespace-prefixes", false);

	Map<String, String> classNameToServletName = new HashMap<String, String>();
	Map<String, Set<String>> servletNameToPaths = new HashMap<String, Set<String>>();
	parser.parse(webXmlUrlString, new WebXmlDataCollector(branch,
	classNameToServletName, servletNameToPaths));

	Map<String, Set<String>> classNameToPaths = new HashMap<String, Set<String>>();
	for (Entry<String, String> entry : classNameToServletName.entrySet()) {
	classNameToPaths.put(entry.getKey(),
	servletNameToPaths.get(entry.getValue()));
	}
	return new ServletValidator(classNameToServletName, classNameToPaths);
	} catch (Exception e) {
	logger.log(TreeLogger.WARN, "Unable to process '" + webXmlUrlString
	+ "' for servlet validation", e);
	return null;
	}
	}

	static String generateMissingMappingMessage(String servletClass,
	String servletPath, String servletName) {
	return "Module declares a servlet class '"
	+ servletClass
	+ "' with a mapping to '"
	+ servletPath
	+ "', but the web.xml has no corresponding mapping; please add the following lines to your web.xml:\n"
	+ ServletWriter.generateServletMappingTag(servletName, servletPath);
	}

	static String generateMissingServletMessage(String servletClass,
	String servletPath) {
	String servletName = suggestServletName(servletClass);
	return "Module declares a servlet class '"
	+ servletClass
	+ "', but the web.xml has no corresponding declaration; please add the following lines to your web.xml:\n"
	+ ServletWriter.generateServletTag(servletName, servletClass) + "\n"
	+ ServletWriter.generateServletMappingTag(servletName, servletPath);
	}

	static String suggestServletName(String servletClass) {
	int pos = servletClass.lastIndexOf('.');
	String suggest = (pos < 0) ? servletClass : servletClass.substring(pos + 1);
	String firstChar = suggest.substring(0, 1).toLowerCase(Locale.ROOT);
	suggest = firstChar + suggest.substring(1);
	return suggest;
	}

	private final Map<String, Set<String>> classNameToPaths;

	private final Map<String, String> classNameToServletName;

	private ServletValidator(Map<String, String> classNameToServletName,
	Map<String, Set<String>> classNameToPaths) {
	this.classNameToServletName = classNameToServletName;
	this.classNameToPaths = classNameToPaths;
	}

	public void validate(TreeLogger logger, String servletClass,
	String servletPath) {
	if (containsServletClass(servletClass)) {
	if (!containsServletMapping(servletClass, servletPath)) {
	String servletName = getNameForClass(servletClass);
	assert (servletName != null);
	logger.log(TreeLogger.WARN, generateMissingMappingMessage(servletClass,
	servletPath, servletName));
	}
	} else {
	logger.log(TreeLogger.WARN, generateMissingServletMessage(servletClass,
	servletPath));
	}
	}

	boolean containsServletClass(String servletClass) {
	return classNameToServletName.get(servletClass) != null;
	}

	boolean containsServletMapping(String servletClass, String servletPath) {
	Set<String> paths = classNameToPaths.get(servletClass);
	return (paths != null) && paths.contains(servletPath);
	}

	String getNameForClass(String servletClass) {
	return classNameToServletName.get(servletClass);
	}
	}