Fixes for the public API of DesignContext.

Also adds tests for parsing and for finding components by id.

Change-Id: I3202a19f1699ee906f97cc57b08a9b2fd540f51b

8 files changed, 323 insertions, 148 deletions

diff --git a/server/src/com/vaadin/ui/AbstractOrderedLayout.java b/server/src/com/vaadin/ui/AbstractOrderedLayout.java
index 139a4eb545..87b2ff6f48 100644
--- a/server/src/com/vaadin/ui/AbstractOrderedLayout.java
+++ b/server/src/com/vaadin/ui/AbstractOrderedLayout.java
@@ -541,7 +541,6 @@ public abstract class AbstractOrderedLayout extends AbstractLayout implements
             DesignSynchronizable childComponent = (DesignSynchronizable) child;
             Element childNode = designContext.createNode(childComponent);
             designElement.appendChild(childNode);
-            childComponent.synchronizeToDesign(childNode, designContext);
             // handle alignment
             Alignment alignment = getComponentAlignment(child);
             if (alignment.isMiddle()) {
diff --git a/server/src/com/vaadin/ui/declarative/ComponentInstantiationException.java b/server/src/com/vaadin/ui/declarative/ComponentInstantiationException.java
deleted file mode 100644
index 5a8ec05d87..0000000000
--- a/server/src/com/vaadin/ui/declarative/ComponentInstantiationException.java
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.vaadin.ui.declarative;
-
-@SuppressWarnings("serial")
-public class ComponentInstantiationException extends RuntimeException {
-
-    public ComponentInstantiationException() {
-        super();
-    }
-
-    public ComponentInstantiationException(String message) {
-        super(message);
-    }
-
-    public ComponentInstantiationException(String message, Throwable e) {
-        super(message, e);
-    }
-
-}
diff --git a/server/src/com/vaadin/ui/declarative/DesignContext.java b/server/src/com/vaadin/ui/declarative/DesignContext.java
index 961affd5b0..a846edff2c 100644
--- a/server/src/com/vaadin/ui/declarative/DesignContext.java
+++ b/server/src/com/vaadin/ui/declarative/DesignContext.java
@@ -31,7 +31,9 @@ import com.vaadin.ui.DesignSynchronizable;
 
 /**
  * This class contains contextual information that is collected when a component
- * tree is constructed based on HTML design template.
+ * tree is constructed based on HTML design template. This information includes
+ * mappings from local ids, global ids and captions to components , as well as a
+ * mapping between prefixes and package names (such as "v" -> "com.vaadin.ui").
  * 
  * @since 7.4
  * @author Vaadin Ltd
@@ -48,12 +50,12 @@ public class DesignContext {
     // id
     public static final String ID_ATTRIBUTE = "id";
     public static final String CAPTION_ATTRIBUTE = "caption";
-    public static final String LOCAL_ID_PREFIX = "_";
-    // Mappings from IDs to components. Modified when synchronizing from design.
-    private Map<String, DesignSynchronizable> globalIdToComponent = new HashMap<String, DesignSynchronizable>();
+    public static final String LOCAL_ID_ATTRIBUTE = "_id";
+    // Mappings from ids to components. Modified when synchronizing from design.
+    private Map<String, DesignSynchronizable> idToComponent = new HashMap<String, DesignSynchronizable>();
     private Map<String, DesignSynchronizable> localIdToComponent = new HashMap<String, DesignSynchronizable>();
     private Map<String, DesignSynchronizable> captionToComponent = new HashMap<String, DesignSynchronizable>();
-    // Mapping from components to local IDs. Accessed when synchronizing to
+    // Mapping from components to local ids. Accessed when synchronizing to
     // design. Modified when synchronizing from design.
     private Map<DesignSynchronizable, String> componentToLocalId = new HashMap<DesignSynchronizable, String>();
     private Document doc; // required for calling createElement(String)
@@ -80,36 +82,73 @@ public class DesignContext {
     }
 
     /**
+     * Returns a component having the specified local id. If no component is
+     * found, returns null.
+     * 
+     * @param localId
+     *            The local id of the component
+     * @return a component whose local id equals localId
+     */
+    public DesignSynchronizable getComponentByLocalId(String localId) {
+        return localIdToComponent.get(localId);
+    }
+
+    /**
+     * Returns a component having the specified global id. If no component is
+     * found, returns null.
+     * 
+     * @param globalId
+     *            The global id of the component
+     * @return a component whose global id equals globalId
+     */
+    public DesignSynchronizable getComponentById(String globalId) {
+        return idToComponent.get(globalId);
+    }
+
+    /**
+     * Returns a component having the specified caption. If no component is
+     * found, returns null.
+     * 
+     * @param caption
+     *            The caption of the component
+     * @return a component whose caption equals the caption given as a parameter
+     */
+    public DesignSynchronizable getComponentByCaption(String caption) {
+        return captionToComponent.get(caption);
+    }
+
+    /**
      * Creates a mapping between the given global id and the component. Returns
-     * true if globalId was already mapped to some component or if component was
-     * mapped to some string. Otherwise returns false. Also sets the id of the
-     * component to globalId.
+     * true if globalId was already mapped to some component. Otherwise returns
+     * false. Also sets the id of the component to globalId.
+     * 
+     * If there is a mapping from the component to a global id (gid) different
+     * from globalId, the mapping from gid to component is removed.
      * 
      * If the string was mapped to a component c different from the given
      * component, the mapping from c to the string is removed. Similarly, if
      * component was mapped to some string s different from globalId, the
      * mapping from s to component is removed.
      * 
-     * @since
      * @param globalId
      *            The new global id of the component.
      * @param component
      *            The component whose global id is to be set.
      * @return true, if there already was a global id mapping from the string to
-     *         some component or from the component to some string. Otherwise
-     *         returns false.
+     *         some component.
      */
-    public boolean mapGlobalId(String globalId, DesignSynchronizable component) {
-        DesignSynchronizable oldComponent = globalIdToComponent.get(globalId);
+    private boolean mapId(String globalId, DesignSynchronizable component) {
+        DesignSynchronizable oldComponent = idToComponent.get(globalId);
         if (oldComponent != null && !oldComponent.equals(component)) {
             oldComponent.setId(null);
         }
         String oldGID = component.getId();
         if (oldGID != null && !oldGID.equals(globalId)) {
-            globalIdToComponent.remove(oldGID);
+            idToComponent.remove(oldGID);
         }
         component.setId(globalId);
-        return oldComponent != null || oldGID != null;
+        idToComponent.put(globalId, component);
+        return oldComponent != null && !oldComponent.equals(component);
     }
 
     /**
@@ -122,8 +161,7 @@ public class DesignContext {
      * component was mapped to some string s different from localId, the mapping
      * from s to component is removed.
      * 
-     * @since
-     * @param globalId
+     * @param localId
      *            The new local id of the component.
      * @param component
      *            The component whose local id is to be set.
@@ -131,7 +169,7 @@ public class DesignContext {
      *         some component or from the component to some string. Otherwise
      *         returns false.
      */
-    public boolean mapLocalId(String localId, DesignSynchronizable component) {
+    private boolean mapLocalId(String localId, DesignSynchronizable component) {
         return twoWayMap(localId, component, localIdToComponent,
                 componentToLocalId);
     }
@@ -146,7 +184,6 @@ public class DesignContext {
      * a given caption can be found using the map captionToComponent. Hence, any
      * captions that are used to identify an object should be unique.
      * 
-     * @since
      * @param caption
      *            The new caption of the component.
      * @param component
@@ -154,7 +191,7 @@ public class DesignContext {
      * @return true, if there already was a caption mapping from the string to
      *         some component.
      */
-    public boolean mapCaption(String caption, DesignSynchronizable component) {
+    private boolean mapCaption(String caption, DesignSynchronizable component) {
         return captionToComponent.put(caption, component) != null;
     }
 
@@ -168,7 +205,6 @@ public class DesignContext {
      * Returns true if there already was a mapping from key to some value v or
      * if there was a mapping from value to some key k. Otherwise returns false.
      * 
-     * @since
      * @param key
      *            The new key in keyToValue.
      * @param value
@@ -198,7 +234,6 @@ public class DesignContext {
      * true if prefix was already mapped to some package name or packageName to
      * some prefix.
      * 
-     * @since
      * @param prefix
      *            the prefix name without an ending dash (for instance, "v" is
      *            always used for "com.vaadin.ui")
@@ -207,7 +242,7 @@ public class DesignContext {
      * @return whether there was a mapping from prefix to some package name or
      *         from packageName to some prefix.
      */
-    public boolean mapPrefixToPackage(String prefix, String packageName) {
+    private boolean mapPrefixToPackage(String prefix, String packageName) {
         return twoWayMap(prefix, packageName, prefixToPackage, packageToPrefix);
     }
 
@@ -240,7 +275,6 @@ public class DesignContext {
      * Get and store the mappings from prefixes to package names from meta tags
      * located under <head> in the html document.
      * 
-     * @since
      */
     public void getPrefixes(Document doc) {
         Element head = doc.head();
@@ -258,7 +292,7 @@ public class DesignContext {
                         String contentString = attributes.get("content");
                         String[] parts = contentString.split(":");
                         if (parts.length != 2) {
-                            throw new LayoutInflaterException("The meta tag '"
+                            throw new DesignException("The meta tag '"
                                     + child.toString() + "' cannot be parsed.");
                         }
                         String prefixName = parts[0];
@@ -297,7 +331,6 @@ public class DesignContext {
      * the synchronizeToDesign() call, this method creates the entire subtree
      * rooted at the returned Node.
      * 
-     * @since
      * @param childComponent
      *            A component implementing the DesignSynchronizable interface.
      * @return An html tree node corresponding to the given component. The tag
@@ -321,8 +354,7 @@ public class DesignContext {
         // care of by synchronizeToDesign.
         String localId = componentToLocalId.get(childComponent);
         if (localId != null) {
-            localId = LOCAL_ID_PREFIX + localId;
-            newElement.attr(localId, "");
+            newElement.attr(LOCAL_ID_ATTRIBUTE, localId);
         }
         return newElement;
     }
@@ -333,7 +365,6 @@ public class DesignContext {
      * inserting a dash before the letter. No dash is inserted before the first
      * letter of the class name.
      * 
-     * @since
      * @param className
      *            the name of the class without a package name
      * @return the html tag name corresponding to className
@@ -359,7 +390,6 @@ public class DesignContext {
      * node. Also calls synchronizeFromDesign() for the created node, in effect
      * creating the entire component hierarchy rooted at the returned component.
      * 
-     * @since
      * @param componentDesign
      *            The html tree node containing the description of the component
      *            to be created.
@@ -370,16 +400,16 @@ public class DesignContext {
         // Create the component.
         DesignSynchronizable component = instantiateComponent(componentDesign);
         component.synchronizeFromDesign(componentDesign, this);
-        // Get the IDs and the caption of the component and store them in the
+        // Get the ids and the caption of the component and store them in the
         // maps of this design context.
         org.jsoup.nodes.Attributes attributes = componentDesign.attributes();
         // global id: only update the mapping, the id has already been set for
         // the component
-        String id = component.getCaption();
+        String id = component.getId();
         if (id != null && id.length() > 0) {
-            boolean mappingExists = mapGlobalId(id, component);
+            boolean mappingExists = mapId(id, component);
             if (mappingExists) {
-                throw new LayoutInflaterException(
+                throw new DesignException(
                         "The following global id is not unique: " + id);
             }
         }
@@ -387,17 +417,12 @@ public class DesignContext {
         // from the attributes of componentDesign
         String localId = null;
         for (Attribute attribute : attributes.asList()) {
-            if (attribute.getKey().startsWith(LOCAL_ID_PREFIX)) {
+            if (attribute.getKey().equals(LOCAL_ID_ATTRIBUTE)) {
                 if (localId != null) {
-                    throw new LayoutInflaterException(
-                            "Duplicate local ids specified: "
-                                    + localId
-                                    + " and "
-                                    + attribute.getKey().substring(
-                                            LOCAL_ID_PREFIX.length()));
+                    throw new DesignException("Duplicate local ids specified: "
+                            + localId + ".");
                 }
-                localId = attribute.getKey()
-                        .substring(LOCAL_ID_PREFIX.length());
+                localId = attribute.getValue();
                 mapLocalId(localId, component); // two-way map
             }
         }
@@ -413,7 +438,6 @@ public class DesignContext {
      * Creates a DesignSynchronizable component corresponding to the given node.
      * Does not set the attributes for the created object.
      * 
-     * @since
      * @param node
      *            a node of an html tree
      * @return a DesignSynchronizable object corresponding to node, with no
@@ -427,16 +451,15 @@ public class DesignContext {
             DesignSynchronizable newComponent = componentClass.newInstance();
             return newComponent;
         } catch (Exception e) {
-            throw createException(e, qualifiedClassName);
+            throw new DesignException("No component class could be found for "
+                    + node.nodeName() + ".", e);
         }
     }
 
     /**
      * Returns the qualified class name corresponding to the given html tree
-     * node. If the node is not a span or a div, the class name is extracted
-     * from the tag name of node.
+     * node. The class name is extracted from the tag name of node.
      * 
-     * @since
      * @param node
      *            an html tree node
      * @return The qualified class name corresponding to the given node.
@@ -445,22 +468,19 @@ public class DesignContext {
         String tagName = node.nodeName();
         if (tagName.equals("v-addon")) {
             return node.attr("class");
-        } else if (tagName.toLowerCase(Locale.ENGLISH).equals("span")
-                || tagName.toLowerCase(Locale.ENGLISH).equals("div")) {
-            return "com.vaadin.ui.Label";
         }
         // Otherwise, get the full class name using the prefix to package
         // mapping. Example: "v-vertical-layout" ->
         // "com.vaadin.ui.VerticalLayout"
         String[] parts = tagName.split("-");
         if (parts.length < 2) {
-            throw new LayoutInflaterException("The tagname '" + tagName
+            throw new DesignException("The tagname '" + tagName
                     + "' is invalid: missing prefix.");
         }
         String prefixName = parts[0];
         String packageName = prefixToPackage.get(prefixName);
         if (packageName == null) {
-            throw new LayoutInflaterException("Unknown tag: " + tagName);
+            throw new DesignException("Unknown tag: " + tagName);
         }
         int firstCharacterIndex = prefixName.length() + 1; // +1 is for '-'
         tagName = tagName.substring(firstCharacterIndex,
@@ -498,20 +518,6 @@ public class DesignContext {
         }
     }
 
-    /*
-     * Create a new ComponentInstantiationException.
-     */
-    private ComponentInstantiationException createException(Exception e,
-            String qualifiedClassName) {
-        String message = String.format(
-                "Couldn't instantiate a component for %s.", qualifiedClassName);
-        if (e != null) {
-            return new ComponentInstantiationException(message, e);
-        } else {
-            return new ComponentInstantiationException(message);
-        }
-    }
-
     /**
      * Returns {@code true} if the given {@link Class} implements the
      * {@link Component} interface of Vaadin Framework otherwise {@code false}.
@@ -532,7 +538,6 @@ public class DesignContext {
     /**
      * Returns the root component of a created component hierarchy.
      * 
-     * @since
      * @return
      */
     public DesignSynchronizable getComponentRoot() {
@@ -545,4 +550,4 @@ public class DesignContext {
     public void setComponentRoot(DesignSynchronizable componentRoot) {
         this.componentRoot = componentRoot;
     }
-}
\ No newline at end of file
+}
diff --git a/server/src/com/vaadin/ui/declarative/DesignException.java b/server/src/com/vaadin/ui/declarative/DesignException.java
new file mode 100644
index 0000000000..74bcd4cdc6
--- /dev/null
+++ b/server/src/com/vaadin/ui/declarative/DesignException.java
@@ -0,0 +1,18 @@
+package com.vaadin.ui.declarative;
+
+@SuppressWarnings("serial")
+public class DesignException extends RuntimeException {
+
+    public DesignException() {
+        super();
+    }
+
+    public DesignException(String message) {
+        super(message);
+    }
+
+    public DesignException(String message, Throwable e) {
+        super(message, e);
+    }
+
+}
diff --git a/server/src/com/vaadin/ui/declarative/LayoutHandler.java b/server/src/com/vaadin/ui/declarative/LayoutHandler.java
index 045fb43b2c..84d454bb01 100644
--- a/server/src/com/vaadin/ui/declarative/LayoutHandler.java
+++ b/server/src/com/vaadin/ui/declarative/LayoutHandler.java
@@ -16,11 +16,8 @@
 package com.vaadin.ui.declarative;
 
 import java.io.BufferedWriter;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.OutputStreamWriter;
 
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
@@ -38,18 +35,17 @@ import com.vaadin.ui.DesignSynchronizable;
  * component hierarchy must contain a single root.
  * 
  * 
- * @since
+ * @since 7.4
  * @author Vaadin Ltd
  */
 public class LayoutHandler {
     /**
      * Constructs a component hierarchy from the design specified as an html
-     * document. The hierarchy must contain exactly one top-level Component. The
-     * component should be located under <body>, but also invalid html
-     * containing the hierarchy without <html>, <head> and <body> tags is
+     * document. The component hierarchy must contain exactly one top-level
+     * Component. The component should be located under <body>, but also invalid
+     * html containing the hierarchy without <html>, <head> and <body> tags is
      * accepted.
      * 
-     * @since
      * @param html
      *            the html document describing the component design
      * @return the DesignContext created while traversing the tree. The
@@ -63,9 +59,37 @@ public class LayoutHandler {
         try {
             doc = Jsoup.parse(html, "UTF-8", "", Parser.htmlParser());
         } catch (IOException e) {
-            throw new LayoutInflaterException(
-                    "The html document cannot be parsed.");
+            throw new DesignException("The html document cannot be parsed.");
         }
+        return parse(doc);
+    }
+
+    /**
+     * Constructs a component hierarchy from the design specified as an html
+     * document given as a string. The component hierarchy must contain exactly
+     * one top-level Component. The component should be located under <body>,
+     * but also invalid html containing the hierarchy without <html>, <head> and
+     * <body> tags is accepted.
+     * 
+     * @param html
+     *            the html document describing the component design
+     * @return the DesignContext created while traversing the tree. The
+     *         top-level component of the created component hierarchy can be
+     *         accessed using result.getRootComponent(), where result is the
+     *         object returned by this method.
+     * @throws IOException
+     */
+    public static DesignContext parse(String html) {
+        Document doc = Jsoup.parse(html);
+        return parse(doc);
+    }
+
+    /**
+     * Constructs a component hierarchy from the design specified as an html
+     * tree.
+     * 
+     */
+    private static DesignContext parse(Document doc) {
         DesignContext designContext = new DesignContext(doc);
         designContext.getPrefixes(doc);
         // No special handling for a document without a body element - should be
@@ -75,7 +99,7 @@ public class LayoutHandler {
         for (Node element : root.childNodes()) {
             if (element instanceof Element) {
                 if (componentRoot != null) {
-                    throw new LayoutInflaterException(
+                    throw new DesignException(
                             "The first level of a component hierarchy should contain a single root component, but found "
                                     + "two: "
                                     + componentRoot
@@ -96,7 +120,6 @@ public class LayoutHandler {
      * the tree. The generated tree corresponds to a valid html document.
      * 
      * 
-     * @since
      * @param root
      *            the root of the component hierarchy
      * @return an html tree representation of the component hierarchy
@@ -126,7 +149,6 @@ public class LayoutHandler {
      * Generates an html file corresponding to the component hierarchy with the
      * given root.
      * 
-     * @since
      * @param writer
      * @param root
      * @throws IOException
@@ -136,32 +158,4 @@ public class LayoutHandler {
         String docAsString = createHtml(ctx).toString();
         writer.write(docAsString);
     }
-
-    /**
-     * Used for testing only.
-     * 
-     * This method reads and constructs a component hierarchy from a file whose
-     * name is given as the first parameter. The constructed hierarchy is then
-     * transformed back to html form, the resulting html being written to a file
-     * whose name is given as the second parameter.
-     * 
-     * This is useful for checking that: 1) a design can be successfully parsed
-     * 2) a component hierarchy can be transformed to html form and 3) No
-     * relevant information is lost in these conversions.
-     * 
-     */
-    public static void main(String[] args) throws IOException {
-        String inputFileName = args[0];
-        String outputFileName = args[1];
-        // Read and parse the contents of the output file.
-        FileInputStream fis = new FileInputStream(inputFileName);
-        DesignContext ctx = parse(fis);
-        DesignSynchronizable root = ctx.getComponentRoot();
-        // Write
-        BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(
-                new FileOutputStream(outputFileName)));
-        createHtml(writer, ctx);
-        fis.close();
-        writer.close();
-    }
-}
\ No newline at end of file
+}
diff --git a/server/src/com/vaadin/ui/declarative/LayoutInflaterException.java b/server/src/com/vaadin/ui/declarative/LayoutInflaterException.java
deleted file mode 100644
index 3482856645..0000000000
--- a/server/src/com/vaadin/ui/declarative/LayoutInflaterException.java
+++ /dev/null
@@ -1,18 +0,0 @@
-package com.vaadin.ui.declarative;
-
-@SuppressWarnings("serial")
-public class LayoutInflaterException extends RuntimeException {
-
-    public LayoutInflaterException(String message) {
-        super(message);
-    }
-
-    public LayoutInflaterException(String message, Throwable e) {
-        super(message, e);
-    }
-
-    public LayoutInflaterException(Throwable e) {
-        super(e);
-    }
-
-}
diff --git a/server/tests/src/com/vaadin/tests/layoutparser/ParseLayoutTest.java b/server/tests/src/com/vaadin/tests/layoutparser/ParseLayoutTest.java
new file mode 100644
index 0000000000..adba5e57b9
--- /dev/null
+++ b/server/tests/src/com/vaadin/tests/layoutparser/ParseLayoutTest.java
@@ -0,0 +1,176 @@
+/*
+ * Copyright 2000-2014 Vaadin Ltd.
+ * 
+ * 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.vaadin.tests.layoutparser;
+
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+
+import junit.framework.TestCase;
+
+import org.jsoup.nodes.Document;
+import org.jsoup.nodes.Element;
+import org.jsoup.nodes.Node;
+import org.junit.Test;
+
+import com.vaadin.ui.Button;
+import com.vaadin.ui.DesignSynchronizable;
+import com.vaadin.ui.HorizontalLayout;
+import com.vaadin.ui.Label;
+import com.vaadin.ui.NativeButton;
+import com.vaadin.ui.TextArea;
+import com.vaadin.ui.TextField;
+import com.vaadin.ui.VerticalLayout;
+import com.vaadin.ui.declarative.DesignContext;
+import com.vaadin.ui.declarative.LayoutHandler;
+
+/**
+ * A test for checking that parsing a layout preserves the IDs and the mapping
+ * from prefixes to package names (for example <meta name=”package-mapping”
+ * content=”my:com.addon.mypackage” />)
+ * 
+ * @since
+ * @author Vaadin Ltd
+ */
+public class ParseLayoutTest extends TestCase {
+    // The context is used for accessing the created component hierarchy.
+    private DesignContext ctx;
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        ctx = LayoutHandler
+                .parse(new FileInputStream(
+                        "server/tests/src/com/vaadin/tests/layoutparser/testFile.html"));
+    }
+
+    /*
+     * Checks the component hierarchy created by parsing a design. Also checks
+     * that components can be found by id and caption.
+     */
+    @Test
+    public void testGettingByIDAndCaption() throws FileNotFoundException {
+        findElements(ctx);
+        checkHierarchy(ctx);
+    }
+
+    /*
+     * Check that captions, ids and package mappings are preserved when an html
+     * tree is generated from a DesignContext containing the component root of
+     * the component hierarchy. Done by writing the design to a string and then
+     * reading it back, not using the original context information after reading
+     * the written design. The mapping from prefixes to package names is checked
+     * directly from the html tree.
+     */
+    @Test
+    public void testThatSerializationPreservesProperties() throws IOException {
+        Document doc = LayoutHandler.createHtml(ctx);
+        DesignContext newContext = LayoutHandler.parse(doc.toString());
+        // Check that the elements can still be found by id and caption
+        findElements(newContext);
+        checkHierarchy(newContext);
+        // Check the mapping from prefixes to package names using the html tree
+        String[] expectedPrefixes = { "my" };
+        String[] expectedPackageNames = { "com.addon.mypackage" };
+        int index = 0;
+        Element head = doc.head();
+        for (Node child : head.childNodes()) {
+            if ("meta".equals(child.nodeName())) {
+                String name = child.attributes().get("name");
+                if ("package-mapping".equals(name)) {
+                    String content = child.attributes().get("content");
+                    String[] parts = content.split(":");
+                    assertEquals("Unexpected prefix.", expectedPrefixes[index],
+                            parts[0]);
+                    assertEquals("Unexpected package name.",
+                            expectedPackageNames[index], parts[1]);
+                    index++;
+                }
+            }
+        }
+        assertEquals("Unexpected number of prefix - package name pairs.", 1,
+                index);
+    }
+
+    /*
+     * Checks that the correct components occur in the correct order in the
+     * component hierarchy rooted at context.getComponentRoot().
+     */
+    private void checkHierarchy(DesignContext context) {
+        DesignSynchronizable root = context.getComponentRoot();
+        VerticalLayout vlayout = (VerticalLayout) root;
+        int numComponents = vlayout.getComponentCount();
+        assertEquals("Wrong number of child components", 3, numComponents);
+
+        // Check the contents of the horizontal layout
+        HorizontalLayout hlayout = (HorizontalLayout) vlayout.getComponent(0);
+        int numHLComponents = hlayout.getComponentCount();
+        assertEquals(5, numHLComponents);
+        Label label = (Label) hlayout.getComponent(0);
+        assertEquals("Wrong caption.", "FooBar", label.getCaption());
+        NativeButton nb = (NativeButton) hlayout.getComponent(1);
+        assertEquals("Wrong caption.", "Native click me", nb.getCaption());
+        nb = (NativeButton) hlayout.getComponent(2);
+        assertEquals("Wrong caption.", "Another button", nb.getCaption());
+        nb = (NativeButton) hlayout.getComponent(3);
+        assertEquals("Wrong caption.", "Yet another button", nb.getCaption());
+        Button b = (Button) hlayout.getComponent(4);
+        assertEquals("Wrong caption.", "Click me", b.getCaption());
+        assertEquals("Wrong width.", 150f, b.getWidth());
+
+        // Check the remaining two components of the vertical layout
+        TextField tf = (TextField) vlayout.getComponent(1);
+        assertEquals("Wrong caption.", "Text input", tf.getCaption());
+        TextArea ta = (TextArea) vlayout.getComponent(2);
+        assertEquals("Wrong caption.", "Text area", ta.getCaption());
+        assertEquals("Wrong width.", 300f, ta.getWidth());
+        assertEquals("Wrong height.", 200f, ta.getHeight());
+    }
+
+    /*
+     * Checks that the correct elements are found using a local id, a global id
+     * or a caption.
+     */
+    private void findElements(DesignContext designContext) {
+        NativeButton firstButton = (NativeButton) designContext
+                .getComponentByLocalId("firstButton");
+        NativeButton firstButton_2 = (NativeButton) designContext
+                .getComponentByCaption("Native click me");
+        NativeButton secondButton = (NativeButton) designContext
+                .getComponentById("secondButton");
+        NativeButton secondButton_2 = (NativeButton) designContext
+                .getComponentByLocalId("localID");
+        NativeButton secondButton_3 = (NativeButton) designContext
+                .getComponentByCaption("Another button");
+        NativeButton thirdButton = (NativeButton) designContext
+                .getComponentByCaption("Yet another button");
+        // Check that the first button was found using both identifiers.
+        assertEquals("The found buttons should be identical but they are not.",
+                firstButton, firstButton_2);
+        assertTrue("The found button element is incorrect.", firstButton
+                .getCaption().equals("Native click me"));
+        // Check that the second button was found using all three identifiers.
+        assertEquals("The found buttons should be identical but they are not.",
+                secondButton, secondButton_2);
+        assertEquals("The found buttons should be identical but they are not.",
+                secondButton_2, secondButton_3);
+        assertTrue("The found button is incorrect.", secondButton.getCaption()
+                .equals("Another button"));
+        // Check that the third button was found by caption.
+        assertTrue("The found button is incorrect.", thirdButton.getCaption()
+                .equals("Yet another button"));
+    }
+}
diff --git a/server/tests/src/com/vaadin/tests/layoutparser/testFile.html b/server/tests/src/com/vaadin/tests/layoutparser/testFile.html
new file mode 100644
index 0000000000..3e4fdc4cd3
--- /dev/null
+++ b/server/tests/src/com/vaadin/tests/layoutparser/testFile.html
@@ -0,0 +1,19 @@
+<!DOCTYPE html>
+<html>
+ <head>
+  <meta name="package-mapping" content="my:com.addon.mypackage"/>
+ </head>
+ <body>
+  <v-vertical-layout width="500px">
+   <v-horizontal-layout>
+    <v-label plain-text caption="FooBar"></v-label>
+    <v-native-button caption="Native click me" _id=firstButton></v-native-button>
+	<v-native-button caption="Another button" id = secondButton _id="localID"></v-native-button>
+	<v-native-button caption="Yet another button"></v-native-button>
+    <v-button plain-text caption="Click me" width = "150px"></v-button>
+   </v-horizontal-layout>
+   <v-text-field caption = "Text input"/>
+   <v-text-area caption = "Text area" height="200px" width="300px"/>
+  </v-vertical-layout>
+ </body>
+</html>
\ No newline at end of file