com.levigo.jadice.document.render
Class PageRenderer

java.lang.Object
  com.levigo.jadice.document.render.AbstractPageRenderer
      com.levigo.jadice.document.render.PageRenderer

public class PageRenderer
extends AbstractPageRenderer

Provides the ability to render the contents of a page into any valid Graphics2D. This class may be used to integrate the jadice document platform rendering of a page for example inside components.

Prior to calling render(Graphics2D) a Page has to be set using AbstractPageRenderer.setPage(Page). If no page has been set, the render(Graphics2D) method will throw an IllegalStateException.

To allow no-blocking rendering of pages on the Event Dispatch Thread, this class allows to register a repaint TaskScope to act as callback. It informs the caller that more page contents are available for immediate rendering. Without the registration of a TaskScope all initialization and preparation work will be done in place, which means that the rendering process will run as long as those tasks need to complete.

Very basic example component using the PageRenderer:

class RenderedPage extends JComponent {
private final PageRenderer renderer;

public RenderedPage() {
super ();
renderer = new PageRenderer() ;

// registering a task scope to act as repaint callback.
// The taskCompleted method will enqueue a repaint of the whole component.
// The taskFailed will report a failure.
TaskScope<RenderResult>taskScope = new TaskScope<RenderResult>() {
@Override
public void taskCompleted(RenderResult result) {
// calling repaint off-EDTis safe, as this will
// only enqueue a paint task in the event queue
repaint();
}

@Override
public void taskFailed(Task<RenderResult>task,Throwable reason) {
// report the failure
LOGGER.error("rendering failed", reason);
}
};

renderer.setRepaintScope(taskScope);
}

public Page getPageToRender() {
return renderer.getPage ();
}

public void setPageToRender (Page page) {
renderer.setPage (page);
repaint();
}

@Override
public void paint( Graphics g) {
Graphics2D g2d = (Graphics2D ) g;

try {
renderer.render(g2d) ;
} catch (JadiceException e ) {
// something did go wrong while initializing or rendering.
System.err.println ("Rendering of Page failed");
e.printStackTrace ();
}
}
}

See Also:

render(Graphics2D), AbstractPageRenderer.setPage(Page), TaskScope, setRepaintScope(TaskScope)

Constructor Summary

PageRenderer()

Method Summary

TaskScope<RenderResult>	getRepaintScope() Request the applied TaskScope.
void	render(Graphics2D target) Paint a Page.
void	setRepaintScope(TaskScope<RenderResult> scope) Supply a TaskScope.

Methods inherited from class com.levigo.jadice.document.render.AbstractPageRenderer

getPage, getRenderControls, setPage, setRenderControls

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PageRenderer

public PageRenderer()

Method Detail

render

public void render(Graphics2D target)
            throws JadiceException

Paint a Page. This method will paint the Page set using AbstractPageRenderer.setPage(Page) or if the Page is null, an IllegalStateException will be thrown.

Specified by:

render in class AbstractPageRenderer

Parameters:

target - the Graphics2D to paint to.

Throws:

IllegalStateException - if page reference is null

JadiceException - will be thrown if the initialization or the rendering of the Page failed.

getRepaintScope

public TaskScope<RenderResult> getRepaintScope()

Request the applied TaskScope.

Returns:

the TaskScope

See Also:

setRepaintScope(TaskScope)

setRepaintScope

public void setRepaintScope(TaskScope<RenderResult> scope)

Supply a TaskScope. It is strongly encouraged to use a TaskScope. Without a TaskScope all initialization and preparation work will be executed on the calling thread. In case of the Event Dispatch Thread, this will force the UI to be unresponsive until the whole process has been completed.

Parameters:

scope - the TaskScope to be used.