GWT

https://www.gwtproject.org/doc/latest/
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### Person POJO example for GWT Editor framework quickstart

Source: https://www.gwtproject.org/doc/latest/DevGuideUiEditors.html

Shows a simple POJO used with the GWT Editor framework. No special types are required; methods are needed for property access.

```java
// Regular POJO, no special types needed
public class Person {
  Address getAddress();
  Person getManager();
  String getName();
  void setManager(Person manager);
  void setName(String name);
}
```

--------------------------------

### loadStockWatcher() setup and loadStocks() call

Source: https://www.gwtproject.org/doc/latest/tutorial/appengine.html

Sets up the stock table's styling and then calls loadStocks() to populate the watch list. The ellipses indicate omitted code that is not part of this example.

```java
private void loadStockWatcher() {

  ...

    stocksFlexTable.setCellPadding(5);
    stocksFlexTable.addStyleName("watchList");
    stocksFlexTable.getRowFormatter().addStyleName(0, "watchListHeader");
    stocksFlexTable.getCellFormatter().addStyleName(0, 1, "watchListNumericColumn");
    stocksFlexTable.getCellFormatter().addStyleName(0, 2, "watchListNumericColumn");
    stocksFlexTable.getCellFormatter().addStyleName(0, 3, "watchListRemoveColumn");

    loadStocks();

  ...

  }

```

--------------------------------

### Quickstart: AutoBean interface declarations, factory, and usage example

Source: https://www.gwtproject.org/doc/latest/DevGuideAutoBeans.html

Shows a complete AutoBean example: declaring bean-like interfaces (Person, Address), a MyFactory interface extending AutoBeanFactory, instantiating beans via GWT.create or AutoBeanFactorySource.create, and serializing/deserializing to JSON. Notes that in non-GWT code, use AutoBeanFactorySource.create(MyFactory.class).

```Java
// Declare any bean-like interface with matching getters and setters, no base type is necessary
interface Person {
  Address getAddress();
  String getName();
  void setName(String name);
  void setAddress(Address a);
}

interface Address {
  // Other properties, as above
}

// Declare the factory type
interface MyFactory extends AutoBeanFactory {
  AutoBean<Address> address();
  AutoBean<Person> person();
}

class DoSomething() {
  // Instantiate the factory
  MyFactory factory = GWT.create(MyFactory.class);
  // In non-GWT code, use AutoBeanFactorySource.create(MyFactory.class);

  Person makePerson() {
    // Construct the AutoBean
    AutoBean<Person> person = factory.person();

    // Return the Person interface shim
    return person.as();
  }

  String serializeToJson(Person person) {
    // Retrieve the AutoBean controller
    AutoBean<Person> bean = AutoBeanUtils.getAutoBean(person);

    return AutoBeanCodex.encode(bean).getPayload();
  }

  Person deserializeFromJson(String json) {
    AutoBean<Person> bean = AutoBeanCodex.decode(factory, Person.class, json);
    return bean.as();
  }
}
```

--------------------------------

### Start BrowserManagerServer

Source: https://www.gwtproject.org/doc/latest/DevGuideTestingRemoteTesting.html

Start the BrowserManagerServer on a remote system to enable RemoteWeb testing, ensuring the GWT JARs are on the classpath.

```bash
java -cp gwt-user.jar;gwt-dev.jar com.google.gwt.junit.remote.BrowserManagerServer ie8 "C:\Program Files\Internet Explorer\IEXPLORE.EXE"
```

--------------------------------

### JSON product data example

Source: https://www.gwtproject.org/doc/latest/DevGuideCodingBasicsJSON.html

Example of JSON encoding product data with nested objects and arrays.

```json
{
  "product": {
    "name": "Widget",
    "company": "ACME, Inc",
    "partNumber": "7402-129",
    "prices": [
      { "minQty": 1, "price": 12.49 },
      { "minQty": 10, "price": 9.99 },
      { "minQty": 50, "price": 7.99 }
    ]
  }
}
```

--------------------------------

### Example event for selecting permutation

Source: https://www.gwtproject.org/doc/latest/DevGuideLightweightMetrics.html

Example of a Lightweight Metrics event for selecting a permutation during GWT startup. Uses the moduleName 'Showcase', subSystem 'startup', evtGroup 'bootstrap', and type 'selectingPermutation'. Note the millis field uses new Date().getTime() and the line ends with a semicolon.

```json
{ 
  moduleName : 'Showcase',
  subSystem : 'startup',
  evtGroup : 'bootstrap',
  millis : new Date().getTime();
  type : 'selectingPermutation'
}

```

--------------------------------

### GWT RuntimeException: Installation problem detected, please reinstall GWT

Source: https://www.gwtproject.org/doc/latest/FAQ_Troubleshooting.html

This is the exception stack trace shown when launching the GWT compiler or development mode fails because the runtime binary installation cannot be located. The error indicates that the installation path is not correctly determined, often because the shared libraries are missing from the classpath. Ensure the path to gwt-dev-<platform>.jar still contains the required shared libraries.

```text
Exception in thread "main" java.lang.ExceptionInInitializerError
Caused by: java.lang.RuntimeException: Installation problem detected, please reinstall GWT
    at com.google.gwt.util.tools.Utility.computeInstallationPath(Utility.java:322)
    at com.google.gwt.util.tools.Utility.getInstallPath(Utility.java:223)
    at com.google.gwt.util.tools.ToolBase.<clinit>(ToolBase.java:55)
Caused by: java.io.IOException: Cannot determine installation directory; apparently not running from a jar
    at com.google.gwt.util.tools.Utility.computeInstallationPath(Utility.java:307)
  ...
```

--------------------------------

### HelloActivity extends AbstractActivity with start(), mayStop(), and goTo()

Source: https://www.gwtproject.org/doc/latest/DevGuideMvpActivitiesAndPlaces.html

A minimal Activity implementation that extends AbstractActivity and implements HelloView.Presenter. It receives a HelloPlace and ClientFactory in its constructor, uses the ClientFactory to obtain the view and PlaceController, and overrides start(), mayStop(), and goTo(). The mayStop() method returns a non-null warning string to prompt the user before stopping; returning null would suppress the warning.

```java
public class HelloActivity extends AbstractActivity implements HelloView.Presenter {
    // Used to obtain views, eventBus, placeController
    // Alternatively, could be injected via GIN
    private ClientFactory clientFactory;
    // Name that will be appended to "Hello,"
    private String name;

    public HelloActivity(HelloPlace place, ClientFactory clientFactory) {
        this.name = place.getHelloName();
        this.clientFactory = clientFactory;
    }

    /**
     * Invoked by the ActivityManager to start a new Activity
     */
    @Override
    public void start(AcceptsOneWidget containerWidget, EventBus eventBus) {
        HelloView helloView = clientFactory.getHelloView();
        helloView.setName(name);
        helloView.setPresenter(this);
        containerWidget.setWidget(helloView.asWidget());
    }

    /**
     * Ask user before stopping this activity
     */
    @Override
    public String mayStop() {
        return "Please hold on. This activity is stopping.";
    }

    /**
     * Navigate to a new Place in the browser
     */
    public void goTo(Place place) {
        clientFactory.getPlaceController().goTo(place);
    }
}

```

--------------------------------

### GWT Hello World with Button and ClickHandler

Source: https://www.gwtproject.org/doc/latest/DevGuideCodingBasicsClient.html

Hello World GWT example that creates a Button widget, attaches a ClickHandler that pops up an alert, and adds the button to the RootPanel. Demonstrates basic widget creation, event handling, and DOM modification in the entry point method.

```java
package com.google.gwt.sample.hello.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.Window;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.Widget;

/**
 * Hello World application.
 */
public class Hello implements EntryPoint {

  public void onModuleLoad() {
    Button b = new Button("Click me", new ClickHandler() {
      public void onClick(ClickEvent event) {
        Window.alert("Hello, AJAX");
      }
    });

    RootPanel.get().add(b);
  }
}

```

--------------------------------

### Final TodoList.java entry point with Polymer.importHref

Source: https://www.gwtproject.org/doc/latest/polymer-tutorial/elements-buildui.html

Final `TodoList.java` entry point. It imports the required Polymer elements and uses `Polymer.importHref` to load them asynchronously, then calls `startApplication()` to add the `Main` widget to the root panel.

```java
package org.gwtproject.tutorial.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.ui.RootPanel;
import com.vaadin.polymer.Polymer;
import com.vaadin.polymer.elemental.Function;
import com.vaadin.polymer.iron.element.IronIconElement;
import com.vaadin.polymer.paper.element.*;

import java.util.Arrays;

public class TodoList implements EntryPoint {

    public void onModuleLoad() {
        Polymer.importHref(Arrays.asList(
                "iron-icons/iron-icons.html",
                PaperIconItemElement.SRC,
                PaperRippleElement.SRC,
                IronIconElement.SRC,
                PaperDrawerPanelElement.SRC,
                PaperHeaderPanelElement.SRC,
                PaperToolbarElement.SRC,
                PaperFabElement.SRC
        ), new Function() {
            public Object call(Object arg) {
                startApplication();
                return null;
            }
        });
    }

    private void startApplication() {
        RootPanel.get().add(new Main());
    }
}
```

--------------------------------

### Final Main.ui.xml with drawer panel and floating action button

Source: https://www.gwtproject.org/doc/latest/polymer-tutorial/elements-buildui.html

Final `Main.ui.xml` file for the tutorial. It defines the complete UI structure with a drawer panel, toolbar, menu items, and the floating action button. The style block uses `is="custom-style"` and includes the `.add` class that sets the `--paper-fab-background` custom property.

```html
<ui:UiBinder xmlns:ui='urn:ui:com.google.gwt.uibinder'
             xmlns:g='urn:import:com.google.gwt.user.client.ui'>

    <g:HTMLPanel>
        <style is="custom-style">
            paper-icon-item {
                position: relative;
                overflow: hidden;
            }
            .toolbar {
                background: #4285f4 !important;
            }
            .header {
                font-size: 200%;
                margin-left: 50px;
            }
            .content {
                padding: 15px;
            }
            .add {
                position: absolute;
                bottom: 20px;
                right: 20px;
                --paper-fab-background: var(--paper-red-500);
            }
        </style>
        <paper-drawer-panel ui:field="drawerPanel">
            <div drawer="">
                <paper-header-panel mode="seamed">
                    <paper-toolbar class="toolbar"/>
                    <paper-icon-item ui:field="menuClearAll">
                        <iron-icon icon="delete" item-icon=""/>
                        <div>Clear All</div>
                        <paper-ripple/>
                    </paper-icon-item>
                    <paper-icon-item ui:field="menuClearDone">
                        <iron-icon icon="clear" item-icon=""/>
                        <div>Clear Done</div>
                        <paper-ripple/>
                    </paper-icon-item>
                    <paper-icon-item ui:field="menuSettings">
                        <iron-icon icon="settings" item-icon=""/>
                        <div>Settings</div>
                        <paper-ripple/>
                    </paper-icon-item>
                    <paper-icon-item ui:field="menuAbout">
                        <iron-icon icon="help" item-icon=""/>
                        <div>About</div>
                        <paper-ripple/>
                    </paper-icon-item>
                </paper-header-panel>
            </div>
            <div main="">
                <paper-header-panel mode="seamed">
                    <paper-toolbar class="toolbar">
                        <paper-icon-button ui:field="menu" icon="more-vert" paper-drawer-toggle=""/>
                        <span class="header">Todo List</span>
                    </paper-toolbar>
                    <div ui:field="content" class="content vertical center-justified layout"/>
                </paper-header-panel>
                <paper-fab ui:field="addButton" icon="add" title="add" class="add"/>
            </div>
        </paper-drawer-panel>
    </g:HTMLPanel>
</ui:UiBinder>
```

--------------------------------

### Capture keyboard events with GWT Event.addNativePreviewHandler

Source: https://www.gwtproject.org/doc/latest/DevGuideUiDom.html

Use this GWT code to intercept keyboard events before they are dispatched to the browser. It registers DOM elements as triggers, checks for interesting keycodes, and consumes the event after handling it. The example shows the required setup with Event.addNativePreviewHandler and the NativePreviewHandler inner class.

```java
private ArrayList<Element> keyboardEventReceivers = new ArrayList<Element>();

/**
 * Widgets can register their DOM element object if they would like to be a
 * trigger to intercept keyboard events
 */
public void registerForKeyboardEvents(Element e) {
  this.keyboardEventReceivers.add(e);
}

/**
 * Returns true if this is one of the keys we are interested in
 */
public boolean isInterestingKeycode(int keycode) {
  // ...
  return false;
}

/**
 * Setup the event preview class when the module is loaded.
 */
private void setupKeyboardShortcuts() {
  // Define an inner class to handle the event
  Event.addNativePreviewHandler(new NativePreviewHandler() {
    public void onPreviewNativeEvent(NativePreviewEvent preview) {
      NativeEvent event = preview.getNativeEvent();

      Element elt = event.getEventTarget().cast();
      int keycode = event.getKeyCode();
      boolean ctrl = event.getCtrlKey();
      boolean shift = event.getShiftKey();
      boolean alt = event.getAltKey();
      boolean meta = event.getMetaKey();
      if (event.getType().equalsIgnoreCase("keypress") || ctrl || shift
          || alt || meta || keyboardEventReceivers.contains(elt)
          || !isInterestingKeycode(keycode)) {
        // Tell the event handler to continue processing this event.
        return;
      }

      GWT.log("Processing Keycode" + keycode, null);
      handleKeycode(keycode);

      // Tell the event handler that this event has been consumed
      preview.consume();
    }
  });
}

/**
 * Perform the keycode specific processing
 */
private void handleKeycode(int keycode) {
  switch (keycode) {
  // ...
  }
}

```

--------------------------------

### Handle RangeChangeEvent to push data into a CellList

Source: https://www.gwtproject.org/doc/latest/DevGuideUiCellWidgets.html

Use this handler to push new data into a CellList when the user pages through the list. The handler receives the new range, creates data for that range (here synchronous, but you could send an asynchronous RPC request), and calls updateRowData(start, data). The example also forces an initial range change with setVisibleRangeAndClearData(new Range(0, 25), true) and sets up a SimplePager to control the list.

```java
/**
 * Example of using a {@link RangeChangeEvent.Handler} to push data into a
 * {@link CellList} when the range changes.
 */
public class RangeChangeHandlerExample implements EntryPoint {

  @Override
  public void onModuleLoad() {
    // Create a CellList.
    CellList<String> cellList = new CellList<String>(new TextCell());

    // Add a range change handler.
    cellList.addRangeChangeHandler(new RangeChangeEvent.Handler() {
      @Override
      public void onRangeChange(RangeChangeEvent event) {
        Range range = event.getNewRange();
        int start = range.getStart();
        int length = range.getLength();

        // Create the data to push into the view. At this point, you could send
        // an asynchronous RPC request to a server.
        List<String> data = new ArrayList<String>();
        for (int i = start; i < start + length; i++) {
          data.add("Item " + i);
        }

        // Push the data into the list.
        updateRowData(start, data);
      }
    });

    // Force the cellList to fire an initial range change event.
    cellList.setVisibleRangeAndClearData(new Range(0, 25), true);

    // Create paging controls.
    SimplePager pager = new SimplePager();
    pager.setDisplay(cellList);

    // Add the widgets to the root panel.
    VerticalPanel vPanel = new VerticalPanel();
    vPanel.add(pager);
    vPanel.add(cellList);
    RootPanel.get().add(vPanel);
  }
}

```

--------------------------------

### Unsplit Hello sample with EntryPoint

Source: https://www.gwtproject.org/doc/latest/DevGuideCodeSplitting.html

Initial version of the Hello sample that comes with GWT. It shows a button that displays an alert when clicked, without any code splitting.

```java
public class Hello implements EntryPoint {
  public void onModuleLoad() {
    Button b = new Button("Click me", new ClickHandler() {
      public void onClick(ClickEvent event) {
        Window.alert("Hello, AJAX");
      }
    });

    RootPanel.get().add(b);
  }
}

```

--------------------------------

### HTML Host Page for GWT Module Loading

Source: https://www.gwtproject.org/doc/latest/DevGuideOrganizingProjects.html

An example HTML page demonstrating the placement of GWT selection scripts and external resources to illustrate the bootstrap sequence.

```html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
  <body onload='alert("w00t!")'>
    <img src='bigImageZero.jpg'></img>
    <script source='externalScriptZero.js'></script>
    <img src='bigImageOne.jpg'></img>
    <img src='reallyBigImageTwo.jpg'></img>
    <script src='myApp/myApp.nocache.js'></script>
    <script src='externalScriptOne.js'></script>
  </body>
</html>
```

--------------------------------

### GWT Plural Forms Example

Source: https://www.gwtproject.org/doc/latest/DevGuideI18nMessages.html

Example of plural forms in English where the message changes based on the count.

```text
You have one tree.
You have 2 trees.
```

--------------------------------

### Launch quoteServer.py from command line

Source: https://www.gwtproject.org/doc/latest/tutorial/Xsite.html

Launch the quoteServer.py script from the command shell. The server starts without immediate output but logs each HTTP request.

```shell
python quoteServer.py
```

--------------------------------

### Import icon collection with Polymer.importHref

Source: https://www.gwtproject.org/doc/latest/polymer-tutorial/widgets-buildui.html

Loads the Iron icon set using Polymer.importHref before starting the application. The callback starts the app only after the import succeeds.

```java
package org.gwtproject.tutorial;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.ui.RootPanel;
import com.vaadin.polymer.Polymer;
import com.vaadin.polymer.elemental.Function;

public class TodoList implements EntryPoint {

  public void onModuleLoad() {
    // We have to load icon sets before run application
    Polymer.importHref("iron-icons/iron-icons.html", new Function() {
        public Object call(Object arg) {
            // The app is executed when all imports succeed.
            startApplication();
            return null;
        }
    });
  }

  private void startApplication() {
    RootPanel.get().add(new Main());
  }
}

```

--------------------------------

### Compile-time error example: Messages interface

Source: https://www.gwtproject.org/doc/latest/DevGuideI18nMessages.html

Java interface for a message that takes two arguments, used in the example that produces a compile-time error due to mismatched parameter count.

```java
public interface ErrorMessages extends Messages {
  String permissionDenied(int errorCode, String username);
}
```

--------------------------------

### Run GWT Compiler with Ant

Source: https://www.gwtproject.org/doc/latest/DevGuideCompilingAndDebugging.html

Example output from running the Ant build script for a GWT project, showing successful compilation and linking of permutations.

```text
C:\gwt-2.6.1\samples\Hello>ant
Buildfile: build.xml

libs:

javac:

gwtc:
     [java] Compiling module com.google.gwt.sample.hello.Hello
     [java]    Compiling 5 permutations
     [java]       Permutation compile succeeded
     [java]    Linking into war
     [java]       Link succeeded
     [java]    Compilation succeeded -- 20.313s

build:

BUILD SUCCESSFUL
Total time: 22 seconds
```

--------------------------------

### Start Xvfb virtual display

Source: https://www.gwtproject.org/doc/latest/FAQ_Troubleshooting.html

Starts Xvfb on display :2 without access control if it is not already running. This command is used to provide a virtual display for GWT compiles and tests in headless environments.

```bash
ps -ef | grep Xvfb | grep -v grep >> /dev/null || Xvfb :2 -ac &

```

--------------------------------

### Implement 9-box Layout with ClientBundle and CSS

Source: https://www.gwtproject.org/doc/latest/DevGuideClientBundle.html

A complete example of a 9-box layout using a ClientBundle interface, CSS with value() functions for dynamic sizing, and the corresponding HTML structure.

```java
public interface Resources extends ClientBundle {
    Resources INSTANCE = GWT.create(Resources.class);

    @Source("bt.png")
    @ImageOptions(repeatStyle = RepeatStyle.Horizontal)
    ImageResource bottomBorder();

    @Source("btl.png")
    ImageResource bottomLeftBorder();

    @Source("btr.png")
    ImageResource bottomRightBorder();

    @Source("StyleInjectorDemo.css")
    CssResource css();

    @Source("lr.png")
    @ImageOptions(repeatStyle = RepeatStyle.Vertical)
    ImageResource leftBorder();

    @Source("rl.png")
    @ImageOptions(repeatStyle = RepeatStyle.Vertical)
    ImageResource rightBorder();

    @Source("tb.png")
    @ImageOptions(repeatStyle = RepeatStyle.Horizontal)
    ImageResource topBorder();

    @Source("tbl.png")
    ImageResource topLeftBorder();

    @Source("tbr.png")
    ImageResource topRightBorder();
  }
```

```css
.contentArea {
  padding: value('topBorder.getHeight', 'px') value('rightBorder.getWidth', 'px')
      value('bottomBorder.getHeight', 'px') value('leftBorder.getWidth', 'px');
}

@sprite .contentAreaTopLeftBorder {
  gwt-image: 'topLeftBorder';
  position: absolute;
  top:0;
  left: 0;
}

@sprite .contentAreaTopBorder {
  gwt-image: 'topBorder';
  position: absolute;
  top: 0;
  left: value('topLeftBorder.getWidth', 'px');
  right: value('topRightBorder.getWidth', 'px');
}

@sprite .contentAreaTopRightBorder {
  gwt-image: 'topRightBorder';
  position: absolute;
  top:0;
  right: 0;
}

@sprite .contentAreaBottomLeftBorder {
  gwt-image: 'bottomLeftBorder';
  position: absolute;
  bottom: 0;
  left: 0;
}

@sprite .contentAreaBottomBorder {
  gwt-image: 'bottomBorder';
  position: absolute;
  bottom: 0;
  left: value('bottomLeftBorder.getWidth', 'px');
  right: value('bottomRightBorder.getWidth', 'px');
}

@sprite .contentAreaBottomRightBorder {
  gwt-image: 'bottomRightBorder';
  position: absolute;
  bottom: 0;
  right: 0;
}

@sprite .contentAreaLeftBorder {
  gwt-image: 'leftBorder';
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
}

@sprite .contentAreaRightBorder {
  gwt-image: 'rightBorder';
  position: absolute;
  top: 0;
  right: 0;
  height: 100%;
}
```

```html
<div class="contentArea">

<div class="contentAreaTopLeftBorder"></div>
<div class="contentAreaTopBorder"></div>
<div class="contentAreaTopRightBorder"></div>
<div class="contentAreaBottomLeftBorder"></div>
<div class="contentAreaBottomBorder"></div>

<div class="contentAreaBottomRightBorder"></div>
<div class="contentAreaLeftBorder"></div>
<div class="contentAreaRightBorder"></div>
</div>
```

--------------------------------

### Create stock table and lay out widgets in StockWatcher onModuleLoad

Source: https://www.gwtproject.org/doc/latest/tutorial/buildui.html

Two sequential versions of the StockWatcher EntryPoint class. The first creates the stock table header row using FlexTable.setText with row 0 and columns 0-3 for Symbol, Price, Change, and Remove. The second assembles the Add Stock panel (HorizontalPanel with TextBox and Button) and the Main panel (VerticalPanel with the table, add panel, and timestamp label), leaving TODO comments for associating with the host page and moving focus.

```java
package com.google.gwt.sample.stockwatcher.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.FlexTable;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

public class StockWatcher implements EntryPoint {

  private VerticalPanel mainPanel = new VerticalPanel();
  private FlexTable stocksFlexTable = new FlexTable();
  private HorizontalPanel addPanel = new HorizontalPanel();
  private TextBox newSymbolTextBox = new TextBox();
  private Button addStockButton = new Button("Add");
  private Label lastUpdatedLabel = new Label();

  /**
   * Entry point method.
   */
  public void onModuleLoad() {
    // Create table for stock data.
    stocksFlexTable.setText(0, 0, "Symbol");
    stocksFlexTable.setText(0, 1, "Price");
    stocksFlexTable.setText(0, 2, "Change");
    stocksFlexTable.setText(0, 3, "Remove");

    // TODO Assemble Add Stock panel.
    // TODO Assemble Main panel.
    // TODO Associate the Main panel with the HTML host page.
    // TODO Move cursor focus to the input box.

  }

}

```

```java
package com.google.gwt.sample.stockwatcher.client;

import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.FlexTable;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

public class StockWatcher implements EntryPoint {

  private VerticalPanel mainPanel = new VerticalPanel();
  private FlexTable stocksFlexTable = new FlexTable();
  private HorizontalPanel addPanel = new HorizontalPanel();
  private TextBox newSymbolTextBox = new TextBox();
  private Button addStockButton = new Button("Add");
  private Label lastUpdatedLabel = new Label();

  /**
   * Entry point method.
   */
  public void onModuleLoad() {
    // Create table for stock data.
    stocksFlexTable.setText(0, 0, "Symbol");
    stocksFlexTable.setText(0, 1, "Price");
    stocksFlexTable.setText(0, 2, "Change");
    stocksFlexTable.setText(0, 3, "Remove");

    // Assemble Add Stock panel.
    addPanel.add(newSymbolTextBox);
    addPanel.add(addStockButton);

    // Assemble Main panel.
    mainPanel.add(stocksFlexTable);
    mainPanel.add(addPanel);
    mainPanel.add(lastUpdatedLabel);

    // TODO Associate the Main panel with the HTML host page.
    // TODO Move cursor focus to the input box.

  }

}

```

--------------------------------

### Java classes for JSNI constructor examples

Source: https://www.gwtproject.org/doc/latest/DevGuideCodingBasicsJSNI.html

Java classes used to illustrate JSNI constructor invocation. The example shows a top-level class with two constructors, a static inner class, and an instance inner class.

```java
package pkg;
class TopLevel {
  public TopLevel() { ... }
  public TopLevel(int i) { ... }

  static class StaticInner {
    public StaticInner() { ... }
  }

  class InstanceInner {
    public InstanceInner(int i) { ... }
  }
}

```

--------------------------------

### Wire MVP together in onModuleLoad()

Source: https://www.gwtproject.org/doc/latest/DevGuideMvpActivitiesAndPlaces.html

EntryPoint that wires together the ClientFactory, ActivityManager, and PlaceHistoryHandler in onModuleLoad(). It sets up the main widget and handles the current history to navigate to the URL place or the default place.

```java
public class HelloMVP implements EntryPoint {
    private Place defaultPlace = new HelloPlace("World!");
    private SimplePanel appWidget = new SimplePanel();

    public void onModuleLoad() {
        ClientFactory clientFactory = GWT.create(ClientFactory.class);
        EventBus eventBus = clientFactory.getEventBus();
        PlaceController placeController = clientFactory.getPlaceController();

        // Start ActivityManager for the main widget with our ActivityMapper
        ActivityMapper activityMapper = new AppActivityMapper(clientFactory);
        ActivityManager activityManager = new ActivityManager(activityMapper, eventBus);
        activityManager.setDisplay(appWidget);

        // Start PlaceHistoryHandler with our PlaceHistoryMapper
        AppPlaceHistoryMapper historyMapper= GWT.create(AppPlaceHistoryMapper.class);
        PlaceHistoryHandler historyHandler = new PlaceHistoryHandler(historyMapper);
        historyHandler.register(placeController, eventBus, defaultPlace);

        RootPanel.get().add(appWidget);
        // Goes to the place represented on URL else default place
        historyHandler.handleCurrentHistory();
    }
}

```

--------------------------------

### Create a CellBrowser with CellBrowser constructor

Source: https://www.gwtproject.org/doc/latest/DevGuideUiCellWidgets.html

Use this constructor to create a CellBrowser instead of a CellTree. The only code difference is the constructor and the CellBrowser.Resources for CSS style and images. The example shows the same data in three levels as the CellTree example, but displayed side-by-side.

```java
// Create the browser using the model.
    CellBrowser browser = new CellBrowser(model, "Item 1");

```

--------------------------------

### Inspect GWT Output Directory

Source: https://www.gwtproject.org/doc/latest/DevGuideCompilingAndDebugging.html

Example file listing of the 'war' directory after a successful GWT compilation, showing generated cache files and the nocache entry point.

```text
C:\gwt-2.6.1\samples\Hello>\bin\find war
war
war\hello
war\hello\18EEC2DA45CB5F0C2050E2539AE61FCE.cache.html
war\hello\813B962DC4C22396EA14405DDEF020EE.cache.html
war\hello\86DA1DCEF4F40731BE71E7978CD4776A.cache.html
war\hello\A37FC20FF4D8F11605B2C4C53AF20B6F.cache.html
war\hello\E3C1ABB32E39A126A9194DB727F7742A.cache.html
war\hello\14A43CD7E24B0A0136C2B8B20D6DF3C0.cache.png
war\hello\548CDF11D6FE9011F3447CA200D7FB7F.cache.png
war\hello\9DA92932034707C17CFF15F95086D53F.cache.png
war\hello\A7CD51F9E5A7DED5F85AD1D82BA67A8A.cache.png
war\hello\B8517E9C2E38AA39AB7C0051564224D3.cache.png
war\hello\clear.cache.gif
war\hello\hello.nocache.js
war\hello\hosted.html
war\Hello.html
```

--------------------------------

### JSNI field access example

Source: https://www.gwtproject.org/doc/latest/DevGuideCodingBasicsJSNI.html

Example of accessing static and instance fields from JSNI. The native method bar demonstrates calling instance and static methods, reading and writing instance fields, and reading a static field. Note the JSNI syntax for method calls and field access.

```java
public class JSNIExample {

  String myInstanceField;
  static int myStaticField;

  void instanceFoo(String s) {
    // use s
  }

  static void staticFoo(String s) {
    // use s
  }

  public native void bar(JSNIExample x, String s) /*-{
    // Call instance method instanceFoo() on this
    this.@com.google.gwt.examples.JSNIExample::instanceFoo(Ljava/lang/String;)(s);

    // Call instance method instanceFoo() on x
    x.@com.google.gwt.examples.JSNIExample::instanceFoo(Ljava/lang/String;)(s);

    // Call static method staticFoo()
    @com.google.gwt.examples.JSNIExample::staticFoo(Ljava/lang/String;)(s);

    // Read instance field on this
    var val = this.@com.google.gwt.examples.JSNIExample::myInstanceField;

    // Write instance field on x
    x.@com.google.gwt.examples.JSNIExample::myInstanceField = val + " and stuff";

    // Read static field (no qualifier)
    @com.google.gwt.examples.JSNIExample::myStaticField = val + " and stuff";
  }-*/;

}

```

--------------------------------

### Create a Maven project with webAppCreator

Source: https://www.gwtproject.org/doc/latest/RefCommandLineTools.html

Command to generate a GWT project using the Maven build system.

```bash
webAppCreator -out foo -templates maven,sample,readme com.example.foo.Foo

```

--------------------------------

### GWT HTML widget constructor and setHTML examples

Source: https://www.gwtproject.org/doc/latest/DevGuideSecuritySafeHtml.html

Two examples of using the HTML widget in GWT. The first passes a compile-time constant string to the HTML constructor, which is safe from XSS. The second passes a variable to setHTML, which may be unsafe if the value is attacker-controlled; prefer setText or Label instead.

```java
HTML widget = new HTML("Some text in the widget");

```

```java
widget.setHTML(someText);

```

--------------------------------

### Create an Ant project with webAppCreator

Source: https://www.gwtproject.org/doc/latest/RefCommandLineTools.html

Command to generate a GWT project using the Ant build system.

```bash
webAppCreator -junit /path/to/junit-3.8.1.jar -out foo com.example.foo.Foo

```

--------------------------------

### Deployment directory structure for DynaTable sample

Source: https://www.gwtproject.org/doc/latest/DevGuideDeploying.html

Shows the required file layout on the servlet container for the DynaTable sample, including the HTML, CSS, and JavaScript files under webapps/dynatable/.

```text
webapps/dynatable/DynaTable.html
webapps/dynatable/DynaTable.css
webapps/dynatable/dynatable/dynatable.nocache.js
// The rest of your GWT application files under webapps/dynatable/dynatable/

```

--------------------------------

### CSS Selector Merging Example

Source: https://www.gwtproject.org/doc/latest/DevGuideClientBundle.html

Shows how rules with identical selectors are combined.

```css
.div {prop: value;}
.div {foo: bar;}
```

```css
.div {prop:value;foo:bar;}
```

--------------------------------

### Run application in SuperDevMode

Source: https://www.gwtproject.org/doc/latest/polymer-tutorial/create.html

After generating the project, navigate into the TodoListApp directory, build the WAR, and start SuperDevMode with Maven. This verifies the project was created correctly.

```bash
$ cd TodoListApp
$ mvn war:exploded
$ mvn gwt:devmode

```

--------------------------------

### English Pluralization Example

Source: https://www.gwtproject.org/doc/latest/DevGuideI18nPluralForms.html

Demonstrates the basic concept of plural forms in English.

```text
You have 1 tree.
You have 2 trees.
```
Tokens:
Raw