Fix some javadoc errors (#8873)

server/src/main/java/com/vaadin/annotations/PropertyId.java

@@ -34,9 +34,9 @@ import com.vaadin.data.HasValue;
  * fields, with the name (ID) of the desired property as the parameter.
  * <p>
  * In following usage example, the text field would be bound to property "foo"
- * in the Entity class. <code>
+ * in the Entity class.
  * <pre>
- *    class Editor extends FormLayout {
+    class Editor extends FormLayout {
         &#64;PropertyId("foo")
         TextField myField = new TextField();
     }
@@ -51,7 +51,6 @@ import com.vaadin.data.HasValue;
         binder.bindInstanceFields(editor);
     }
    </pre>
- * </code>
  *
  * @since 8.0
  * @author Vaadin Ltd

server/src/main/java/com/vaadin/data/HasItems.java

@@ -56,7 +56,7 @@ public interface HasItems<T> extends Component, Serializable {
      *
      * <pre>
      * <code>
-     * HasDataProvider<String> listing = new CheckBoxGroup<>();
+     * HasDataProvider&lt;String&gt; listing = new CheckBoxGroup&lt;&gt;();
      * listing.setItems(Arrays.asList("a","b"));
      * ...
      *
@@ -121,11 +121,11 @@ public interface HasItems<T> extends Component, Serializable {
      *
      * <pre>
      * <code>
-     * HasDataProvider<String> listing = new CheckBoxGroup<>();
+     * HasDataProvider&lt;String&gt; listing = new CheckBoxGroup<&gt;();
      * listing.setItems(Stream.of("a","b"));
      * ...
      *
-     * Collection<String> collection = ((ListDataProvider<String>)listing.getDataProvider()).getItems();
+     * Collection<String> collection = ((ListDataProvider&lt;String&gt;)listing.getDataProvider()).getItems();
      * </code>
      * </pre>
      * <p>

server/src/main/java/com/vaadin/data/SelectionModel.java

@@ -204,7 +204,7 @@ public interface SelectionModel<T> extends Serializable {
          * If all the added items were already selected and the removed items
          * were not selected, this is a NO-OP.
          * <p>
-         * Duplicate items (in both add & remove sets) are ignored.
+         * Duplicate items (in both add &amp; remove sets) are ignored.
          *
          * @param addedItems
          *            the items to add, not {@code null}

server/src/main/java/com/vaadin/data/Validator.java

@@ -31,8 +31,8 @@ import com.vaadin.server.SerializablePredicate;
  * For instance, the following validator checks if a number is positive:
  *
  * <pre>
- * Validator&lt;Integer&gt; v = num -> {
- *     if (num >= 0)
+ * Validator&lt;Integer&gt; v = num -&gt; {
+ *     if (num &gt;= 0)
  *         return ValidationResult.ok();
  *     else
  *         return ValidationResult.error("number must be positive");
@@ -87,7 +87,7 @@ public interface Validator<T>
      * 10, inclusive:
      *
      * <pre>
-     * Validator&lt;Integer&gt; v = Validator.from(num -> num >= 0 && num <= 10,
+     * Validator&lt;Integer&gt; v = Validator.from(num -&gt; num &gt;= 0 && num &lt;= 10,
      *         "number must be between 0 and 10");
      * </pre>
      *

server/src/main/java/com/vaadin/event/ShortcutAction.java

@@ -141,15 +141,15 @@ public class ShortcutAction extends Action {
      * Insert one or more modifier characters before the character to use as
      * keycode. E.g <code>"&Save"</code> will make a shortcut responding to
      * ALT-S, <code>"E^xit"</code> will respond to CTRL-X.<br/>
-     * Multiple modifiers can be used, e.g <code>"&^Delete"</code> will respond
+     * Multiple modifiers can be used, e.g <code>"&amp;^Delete"</code> will respond
      * to CTRL-ALT-D (the order of the modifier characters is not important).
      * </p>
      * <p>
      * The modifier characters will be removed from the caption. The modifier
      * character is be escaped by itself: two consecutive characters are turned
      * into the original character w/o the special meaning. E.g
-     * <code>"Save&&&close"</code> will respond to ALT-C, and the caption will
-     * say "Save&close".
+     * <code>"Save&amp;&amp;&amp;close"</code> will respond to ALT-C, and the caption will
+     * say "Save&amp;close".
      * </p>
      *
      * @param shorthandCaption
@@ -168,7 +168,7 @@ public class ShortcutAction extends Action {
      * caption. I.e use any of the modifier characters in the caption to
      * indicate the keycode, but the modifier will be the given set.<br/>
      * E.g
-     * <code>new ShortcutAction("Do &stuff", new int[]{ShortcutAction.ModifierKey.CTRL}));</code>
+     * <code>new ShortcutAction("Do &amp;stuff", new int[]{ShortcutAction.ModifierKey.CTRL}));</code>
      * will respond to CTRL-S.
      * </p>
      *

server/src/main/java/com/vaadin/server/ClientConnector.java

@@ -223,7 +223,7 @@ public interface ClientConnector extends Connector {
      * Notifies the connector that it is connected to a VaadinSession (and
      * therefore also to a UI).
      * <p>
-     * The caller of this method is {@link #setParent(ClientConnector)} if the
+     * The caller of this method is {@link Connector#setParent(ClientConnector)} if the
      * parent is itself already attached to the session. If not, the parent will
      * call the {@link #attach()} for all its children when it is attached to
      * the session. This method is always called before the connector's data is

server/src/main/java/com/vaadin/ui/Component.java

@@ -616,17 +616,17 @@ public interface Component extends ClientConnector, Sizeable, Serializable {
      * <td width=120><b>Example</b></td>
      * </tr>
      * <tr>
-     * <td>&lt;b></td>
+     * <td>&lt;b&gt;</td>
      * <td>bold</td>
      * <td><b>bold text</b></td>
      * </tr>
      * <tr>
-     * <td>&lt;i></td>
+     * <td>&lt;i&gt;</td>
      * <td>italic</td>
      * <td><i>italic text</i></td>
      * </tr>
      * <tr>
-     * <td>&lt;u></td>
+     * <td>&lt;u&gt;</td>
      * <td>underlined</td>
      * <td><u>underlined text</u></td>
      * </tr>
@@ -636,10 +636,10 @@ public interface Component extends ClientConnector, Sizeable, Serializable {
      * <td>N/A</td>
      * </tr>
      * <tr>
-     * <td>&lt;ul><br>
-     * &lt;li>item1<br>
-     * &lt;li>item1<br>
-     * &lt;/ul></td>
+     * <td>&lt;ul&gt;<br>
+     * &lt;li&gt;item1<br>
+     * &lt;li&gt;item1<br>
+     * &lt;/ul&gt;</td>
      * <td>item list</td>
      * <td>
      * <ul>

shared/src/main/java/com/vaadin/shared/util/SharedUtil.java

@@ -243,7 +243,7 @@ public class SharedUtil implements Serializable {
      * @param uri
      *            The uri to which the parameters should be added.
      * @param extraParams
-     *            One or more parameters in the format "a=b" or "c=d&e=f". An
+     *            One or more parameters in the format "a=b" or "c=d&e=f". An
      *            empty string is allowed but will not modify the url.
      * @return The modified URI with the get parameters in extraParams added.
      */