Comment faire pour afficher les documents PDF en VAADIN

Vous pouvez utiliser l'exemple figurant dans Vaadin documentation

https://vaadin.com/book/-/page/advanced.printing.html (voir 11.6.3. Impression PDF)

    //A user interface for a (trivial) data model from which
    //the PDF is generated.
    final TextField name = new TextField("Name");
    name.setValue("Slartibartfast");

    //This has to be clicked first to create the stream resource
    final Button ok = new Button("OK");

    //This actually opens the stream resource
    final Button print = new Button("Open PDF");
    print.setEnabled(false);

    ok.addClickListener(new ClickListener() {
        @Override
        public void buttonClick(ClickEvent event) {
            //Create the PDF source and pass the data model to it
            StreamSource source =
                new MyPdfSource((String) name.getValue());

            //Create the stream resource and give it a file name
            String filename = "pdf_printing_example.pdf";
            StreamResource resource =
                    new StreamResource(source, filename);

            //These settings are not usually necessary. MIME type
            //is detected automatically from the file name, but
            //setting it explicitly may be necessary if the file
            //suffix is not ".pdf".
            resource.setMIMEType("application/pdf");
            resource.getStream().setParameter(
                    "Content-Disposition",
                    "attachment; filename="+filename);

            //Extend the print button with an opener
            //for the PDF resource
            BrowserWindowOpener opener =
                    new BrowserWindowOpener(resource);
            opener.extend(print);

            name.setEnabled(false);
            ok.setEnabled(false);
            print.setEnabled(true);
        }
    });


    layout.addComponent(name);
    layout.addComponent(ok);
    layout.addComponent(print);

Autre exemple utile:

        package com.vaadin.book.examples.advanced;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.util.Date;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.sax.SAXResult;
import org.apache.fop.apps.FOUserAgent;
import org.apache.fop.apps.Fop;
import org.apache.fop.apps.FopFactory;
import org.apache.fop.apps.MimeConstants;
import com.vaadin.book.examples.BookExampleBundle;
import com.vaadin.terminal.ExternalResource;
import com.vaadin.terminal.StreamResource;
import com.vaadin.terminal.StreamResource.StreamSource;
import com.vaadin.ui.Button;
import com.vaadin.ui.Button.ClickEvent;
import com.vaadin.ui.Button.ClickListener;
import com.vaadin.ui.CustomComponent;
import com.vaadin.ui.Label;
import com.vaadin.ui.TextField;
import com.vaadin.ui.VerticalLayout;
import com.vaadin.ui.Window;
public class PrintingExample extends CustomComponent implements BookExampleBundle {
private static final long serialVersionUID = 97529549237L;
public void init(String context) {
VerticalLayout layout = new VerticalLayout();
if ("this".equals(context))
printThisPage();
else if ("open".equals(context))
printOpenedPage();
else if ("nonblocking".equals(context))
printNonblockingPage();
else if ("pdfgeneration".equals(context))
pdfgeneration(layout);
else
setCompositionRoot(new Label("Invalid Context"));
if (getCompositionRoot() == null)
setCompositionRoot(layout);
}
void printThisPage () {
//BEGIN-EXAMPLE: advanced.printing.this
final Button print = new Button("Print This Page");
print.addListener(new ClickListener() {
private static final long serialVersionUID = 15335453452L;
public void buttonClick(ClickEvent event) {
print.getWindow().executeJavaScript("print();");
}
});
//END-EXAMPLE: advanced.printing.this
setCompositionRoot(print);
}
void printOpenedPage () {
//BEGIN-EXAMPLE: advanced.printing.open
//A button to open the printer-friendly page.
Button print = new Button("Click to Print");
print.addListener(new Button.ClickListener() {
private static final long serialVersionUID = 6588417468637527327L;
public void buttonClick(ClickEvent event) {
//Create a window that contains what you want to print
Window window = new Window("Window to Print");
//Have some content to print
window.addComponent(new Label(
"<h1>Here's some dynamic content</h1>\n" +
"<p>This is to be printed to the printer.</p>",
Label.CONTENT_XHTML));
//Add the printing window as a new application-level
//window
getApplication().addWindow(window);
//Open it as a popup window with no decorations
getWindow().open(new ExternalResource(window.getURL()),
"_blank", 500, 200,  //Width and height 
Window.BORDER_NONE); //No decorations
//Print automatically when the window opens.
//This call will block until the print dialog exits!
window.executeJavaScript("print();");
//Close the window automatically after printing
window.executeJavaScript("self.close();");
}
});
//END-EXAMPLE: advanced.printing.open
setCompositionRoot(print);
}
//TODO: This actually blocks also.
void printNonblockingPage () {
//A button to open the printer-friendly page.
final Button print = new Button("Click to Print");
print.addListener(new Button.ClickListener() {
private static final long serialVersionUID = 349852897523897L;
public void buttonClick(ClickEvent event) {
//Content to be printed. Must double-quote newlines.
String content = "<h1>Stuff to Print</h1>\\n" +
"<p>Important stuff</p>\\n";
//The code to print and close the window
content += "<SCRIPT language=\"JavaScript\">" +
"  print();" +
"  close();" +
"</SCRIPT>";
//Open the print window
String js = "popup = window.open('', 'mywindow','status=1,width=350,height=150');\n" +
"popup.document.write('"+content+"');\n";
print.getWindow().executeJavaScript(js);
}
});
setCompositionRoot(print);
}
public final static String pdfgenerationDescription =
"<h1>Generating a Printable PDF</h1>" +
"<p>You can generate a PDF file dynamically using a <b>StreamResource</b>. The following example does it using the Apache FOP.</p>";
//BEGIN-EXAMPLE: advanced.printing.pdfgeneration
/** Generates the PDF dynamically when requested by HTTP. */
class MyPdfSource implements StreamSource {
private static final long serialVersionUID = 6580720404794033932L;
String name; //A trivial content data model
/** Constructor gets a content data model as parameter */
public MyPdfSource(String name) {
this.name = name;
}
@Override
public InputStream getStream() {
//Generate the FO content. You could use the Java DOM API
//here as well and pass the DOM to the transformer.
String fo = "<?xml version='1.0' encoding='ISO-8859-1'?>\n"+
"<fo:root xmlns:fo='http://www.w3.org/1999/XSL/Format'>\n"+
"<fo:layout-master-set>"+
"  <fo:simple-page-master master-name='A4' margin='2cm'>"+
"    <fo:region-body />"+
"  </fo:simple-page-master>"+
"</fo:layout-master-set>"+
"<fo:page-sequence master-reference='A4'>"+
"    <fo:flow flow-name='xsl-region-body'>"+
"    <fo:block text-align='center'>"+
"Hello There, "+ name + "!</fo:block>"+
"  </fo:flow>"+
"</fo:page-sequence>"+
"</fo:root>\n";
ByteArrayInputStream foStream =
new ByteArrayInputStream(fo.getBytes());
//Basic FOP configuration. You could create this object
//just once and keep it.
FopFactory fopFactory = FopFactory.newInstance();
fopFactory.setStrictValidation(false); //For an example
//Configuration for this PDF document - mainly metadata
FOUserAgent userAgent = fopFactory.newFOUserAgent();
userAgent.setProducer("My Vaadin Application");
userAgent.setCreator("Me, Myself and I");
userAgent.setAuthor("Da Author");
userAgent.setCreationDate(new Date());
userAgent.setTitle("Hello to " + name);
userAgent.setKeywords("PDF Vaadin example");
userAgent.setTargetResolution(300); //DPI
//Transform to PDF
ByteArrayOutputStream fopOut = new ByteArrayOutputStream();
try {
Fop fop = fopFactory.newFop(MimeConstants.MIME_PDF,
userAgent, fopOut);
TransformerFactory factory =
TransformerFactory.newInstance();
Transformer transformer = factory.newTransformer();
Source src = new
javax.xml.transform.stream.StreamSource(foStream);
Result res = new SAXResult(fop.getDefaultHandler());
transformer.transform(src, res);
fopOut.close();
return new ByteArrayInputStream(fopOut.toByteArray());
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}
void pdfgeneration(VerticalLayout layout) {
//A user interface for a data model from which
//the PDF is generated.
final TextField name = new TextField("Name");
name.setValue("Slartibartfast");
Button print = new Button("Open PDF");
print.addListener(new ClickListener() {
private static final long serialVersionUID = 1269425538593656695L;
@Override
public void buttonClick(ClickEvent event) {
//Create the PDF source and pass the data model to it
StreamSource source =
new MyPdfSource((String) name.getValue());
//Create the stream resource and give it a file name
String filename = "pdf_printing_example.pdf";
StreamResource resource = new StreamResource(source,
filename, getApplication());
//These settings are not usually necessary. MIME type
//is detected automatically from the file name, but
//setting it explicitly may be necessary if the file
//suffix is not ".pdf".
resource.setMIMEType("application/pdf");
resource.getStream().setParameter("Content-Disposition",
"attachment; filename="+filename);
//Open it in this window - this will either launch
//PDF viewer or let the user download the file. Could
//use "_blank" target to open in another window, but
//may not be necessary.
getWindow().open(resource);
}
});
layout.addComponent(name);
layout.addComponent(print);
}
//END-EXAMPLE: advanced.printing.pdfgeneration
}

http://dev.vaadin.com/svn/doc/book-examples/trunk/src/com/vaadin/book/examples/advanced/PrintingExample.java

OriginalL'auteur Marcelo Bezerra