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Exported SVG overflows boundaries

I am visualizing some data with vaadin-charts:3.2.0, and I am trying to export a SVG out from the chart. I get some results but it is not satisfying. I can only share the screenshosts instead of the SVG itself. I also had to pixelate the labels to mask private data.
Original vaadin-charts seen on screen:
Exported SVG:
One problem is that the labels overflow the svg boundaries. And the chart drawings also overflow the boundaries making it seem like an incomplete drawing. Any idea what is wrong with this structure?
public class SvgStreamResource extends StreamResource {
public SvgStreamResource(String svgText, String filename) {
super(new StreamSource() {
#Override
public InputStream getStream() {
InputStream s = new BufferedInputStream( new ReaderInputStream(new StringReader(svgText)));
return s;
}
}, filename + ".svg");
}
#Override
public String getMIMEType() {
return "image/svg+xml";
}
}
Within a component:
Button exportButton = createExportButton("SVG", createSVGStreamSource(conf));
private SvgStreamResource createSVGStreamSource(Configuration conf) {
String svg = SVGGenerator.getInstance().generate(conf);
return new SvgStreamResource(svg, fileBaseName);
}
private Button createExportButton(String caption, SvgStreamResource svgStreamResource) {
Button b = new Button(caption);
FileDownloader downloader = new FileDownloader(svgStreamResource);
downloader.extend(b);
return b;
}

How to pass data from vaadin webapp to C# GUI app

I have webapp in Vaadin Framework 8. I have Windows GUI app in C#.
The gui app is using WebBrowser component to display webapp. WebBrowser component is internally using IE11 core through ActiveX. I can successfully load and display the webapp in the gui app browser component.
I need to pass data from webapp to the gui app.
The webapp has many rows loaded on server side, only few are displayed in grid. I want to pass all data from webapp to gui app in some format (csv or json).
I have tryed some approaches, but I wasn't successfull.
[Approach 1]
Webapp: attach downloadable resource (csv) to Link with predefined id using FileDownloader. Download by user mouse click works fine, file save dialog pops up and data are downloaded successfully.
Link link = new Link("Data");
link.setId("myId");
StreamResource resource = getMyResource(data);
FileDownloader downloader = new FileDownloader(resource);
downloader.extend(link);
Page.getCurrent().getJavaScript().addFunction("test", new JavaScriptFunction() {
#Override
public void call(JsonArray arguments) {
Page.getCurrent().getJavaScript()
.execute("document.getElementById('myId').click()");
}
});
Gui app: raise onClick event on link and capture WebBrowser.FileDownload event, capture WebBrowser.Navigate event.
I have failed to raise onClick event from C# using:
HtmlElement el = webBrowser.Document.GetElementById("myId");
el.RaiseEvent("onClick");
el.InvokeMember("click");
webBrowser.Document.InvokeScript("document.getElementById('myId').click();", null);
webBrowser.Document.InvokeScript("test", null);
Result:
WebBrowser.FileDownload event doesn't work (is fired but can't capture url nor data), capture WebBrowser.Navigate event works partialy (can see resource url, but can't download data using byte[] b = new WebClient().DownloadData(e.Url);).
[Approach 2]
Similar to approach 1. I tryed to get resource url, put the direct url to Link and download the resource in c# using direct link. I can construct the same resource url as is used by browser to download data when user clicks the link.
Extended file downloader that keeps resource, key and connector:
public class ExtendedFileDownloader extends FileDownloader {
private String myKey;
private Resource myResource;
private ClientConnector myConnector;
public ExtendedFileDownloader(StreamResource resource, ClientConnector connector) {
super(resource);
myConnector = connector;
}
#Override
protected void setResource(String key, Resource resource) {
super.setResource(key, resource);
myKey = key;
myResource = resource;
}
public String getResourceUrl() {
ResourceReference ref =
ResourceReference.create(
myResource,
(myConnector != null) ? myConnector : this,
myKey);
String url = ref.getURL();
return url;
}
}
In view:
// fix app://path... urls to /<base-path>/path urls
private String fixResourceReferenceUrl(String resourceReferenceUrl) {
String resourceReferencePath = resourceReferenceUrl.replace("app://", "");
String uiBaseUrl = ui.getUiRootPath();
String fixedUrl = uiBaseUrl + "/" + resourceReferencePath;
return fixedUrl;
}
Link link2 = new Link("Data2");
link2.setId("myId2");
StreamResource resource = getMyResource(data);
ExtendedFileDownloader downloader = new ExtendedFileDownloader(resource, this);
String fixedResourceUrl = fixResourceReferenceUrl(downloader.getResourceUrl());
link2.setResource(new ExternalResource(fixedResourceUrl));
Result:
The data cannot be downloaded using this link, server error 410 or NotFound errors.
Any Ideas ? Any other approaches to try ?

I have finally solved the problem. The solution is very close to approach 2.
The resource url is passed in element with custom attribute. C# WebClient needs to set cookies from WebBrowser and Referer HTTP headers. The data can be successfully downloaded by C# app.
Element attribute in vaadin webapp can be set using Vaadin-addon Attributes.
Cookies in C# app can be retrieved using this solution.
// Fix resource urls begining with app://
public String fixResourceReferenceUrl(String resourceReferenceUrl) {
try {
String uiRootPath = UI.getCurrent().getUiRootPath();
URI location = Page.getCurrent().getLocation();
String appLocation = new URIBuilder()
.setScheme(location.getScheme())
.setHost(location.getHost())
.setPort(location.getPort())
.setPath(uiRootPath)
.build()
.toString();
String resourceReferencePath = resourceReferenceUrl.replace("app://", "");
String fixedUrl = appLocation + "/" + resourceReferencePath;
return fixedUrl;
}
catch (Exception e) {
return null;
}
}
In view (using ExtendedFileDownloader from above):
Link link = new Link("Data");
link.setId("myId");
StreamResource resource = getMyResource(data);
ExtendedFileDownloader downloader = new ExtendedFileDownloader(resource);
downloader.extend(link);
Attribute attr = new Attribute("x-my-data", fixResourceReferenceUrl(downloader.getResourceUrl()));
attr.extend(link);
link.setVisible(true);
In C# app:
[DllImport("wininet.dll", SetLastError = true)]
public static extern bool InternetGetCookieEx(
string url,
string cookieName,
StringBuilder cookieData,
ref int size,
Int32 dwFlags,
IntPtr lpReserved);
private const Int32 InternetCookieHttponly = 0x2000;
public static String GetUriCookies(String uri)
{
// Determine the size of the cookie
int datasize = 8192 * 16;
StringBuilder cookieData = new StringBuilder(datasize);
if (!InternetGetCookieEx(uri, null, cookieData, ref datasize, InternetCookieHttponly, IntPtr.Zero))
{
if (datasize < 0)
return null;
// Allocate stringbuilder large enough to hold the cookie
cookieData = new StringBuilder(datasize);
if (!InternetGetCookieEx(
uri,
null, cookieData,
ref datasize,
InternetCookieHttponly,
IntPtr.Zero))
return null;
}
return cookieData.ToString();
}
private void button_Click(object sender, EventArgs e)
{
HtmlElement el = webBrowser.Document.GetElementById("myId");
String url = el.GetAttribute("x-my-data");
String cookies = GetUriCookies(url);
WebClient wc = new WebClient();
wc.Headers.Add("Cookie", cookies);
wc.Headers.Add("Referer", WEB_APP_URL); // url of webapp base path, http://myhost/MyUI
byte[] data = wc.DownloadData(url);
}

How to retrieve the image of a PdfStampAnnotation

I created a pdf using the following example:
https://developers.itextpdf.com/examples/actions-and-annotations/clone-creating-and-adding-annotations#2260-addstamp.java
#Category(SampleTest.class)
public class AddStamp extends GenericTest {
public static final String DEST = "./target/test/resources/sandbox/annotations/add_stamp.pdf";
public static final String IMG = "./src/test/resources/img/itext.png";
public static final String SRC = "./src/test/resources/pdfs/hello.pdf";
public static void main(String[] args) throws Exception {
File file = new File(DEST);
file.getParentFile().mkdirs();
new AddStamp().manipulatePdf(DEST);
}
#Override
protected void manipulatePdf(String dest) throws Exception {
PdfDocument pdfDoc = new PdfDocument(new PdfReader(SRC), new PdfWriter(DEST));
ImageData img = ImageDataFactory.create(IMG);
float w = img.getWidth();
float h = img.getHeight();
Rectangle location = new Rectangle(36, 770 - h, w, h);
PdfStampAnnotation stamp = new PdfStampAnnotation(location)
.setStampName(new PdfName("ITEXT"));
PdfFormXObject xObj = new PdfFormXObject(new Rectangle(w, h));
PdfCanvas canvas = new PdfCanvas(xObj, pdfDoc);
canvas.addImage(img, 0, 0, false);
stamp.setNormalAppearance(xObj.getPdfObject());
stamp.setFlags(PdfAnnotation.PRINT);
pdfDoc.getFirstPage().addAnnotation(stamp);
pdfDoc.close();
}
}
The pdf is properly created and contains the stamp annotation
I can get the annotation using:
...
PdfStampAnnotation s = (PdfStampAnnotation) pdfDoc.getFirstPage().getAnnotations().get(0);
s.?????
How can I get back the image (itext.png) of the stamp (eg: byte[]) ?
I'm really new to itext and after hours of research I'm stuck at this point...

First of all, you won't get the original image back. PDF support only very few bitmap image formats as they are: JPEG, JPEG2000, certain fax formats, but definitively not PNG. PNGs are converted into the PDF internal bitmap format, and upon extraction can best be converted back to a PNG.
Furthermore, the reason why there is no simple getImage method in the PdfStampAnnotation class is that the appearance of a stamp may be constructed like the contents of a regular page, it may contain text, it may contain vector graphics, it may contain bitmap images, it may contain an arbitrary mixture of those elements. Thus, all you can retrieve from an annotation is its appearance.
If you are sure an annotation contains only an image (or you at least are not interested in anything but the image), you can extract that image using the iText parser framework, e.g. like this:
Map<byte[], String> extractAnnotationImages(PdfStream xObject) {
final Map<byte[], String> result = new HashMap<>();
IEventListener renderListener = new IEventListener() {
#Override
public Set<EventType> getSupportedEvents() {
return Collections.singleton(RENDER_IMAGE);
}
#Override
public void eventOccurred(IEventData data, EventType type) {
if (data instanceof ImageRenderInfo) {
ImageRenderInfo imageRenderInfo = (ImageRenderInfo) data;
byte[] bytes = imageRenderInfo.getImage().getImageBytes();
String extension = imageRenderInfo.getImage().identifyImageFileExtension();
result.put(bytes, extension);
}
}
};
PdfCanvasProcessor processor = new PdfCanvasProcessor(renderListener, Collections.emptyMap());
processor.processContent(xObject.getBytes(), new PdfResources(xObject.getAsDictionary(PdfName.Resources)));
return result;
}
(ExtractAnnotationImage method)
which returns a mapping from image byte arrays to file extension to use.
I used it in this helper method:
void saveAnnotationImages(PdfDocument pdfDocument, String prefix) throws IOException {
for (int pageNumber = 1; pageNumber <= pdfDocument.getNumberOfPages(); pageNumber++) {
PdfPage page = pdfDocument.getPage(pageNumber);
int index = 0;
for (PdfAnnotation annotation : page.getAnnotations()) {
PdfDictionary normal = annotation.getAppearanceObject(PdfName.N);
if (normal instanceof PdfStream) {
Map<byte[], String> images = extractAnnotationImages((PdfStream)normal);
for (Map.Entry<byte[], String> entry : images.entrySet()) {
Files.write(new File(String.format("%s-%s-%s.%s", prefix, pageNumber, index++, entry.getValue())).toPath(), entry.getKey());
}
}
}
}
}
(ExtractAnnotationImage helper method)
to extract all images from annotations from the output of the iText example AddStamp you reference and got one image:
By the way, you'll recognize here that transparency is missing. Transparency in the PDF is modeled via a second image, a mask image, which effectively represents something like an alpha channel. One can retrieve this mask from the ImageRenderInfo.getImage() object.

How to retrieve images from server to user using Struts 2

I have a Product entity, which has a imageUrl String field.
Products images after obtaining from user will be saved in directory:
System.getProperty("user.home") + "shop/data/product/"
And when user wants to see some Product I need to get this image from "user.home"+... to JSP page.
I've tried to read the image into the byte array, convert it to Base64 encoding, and then refer in JSP like this:
<img alt="image from user home" src="data:image/png, base64;${requestScope.image}">
But this solution is not working, and as far as I understand, it has a limitation on image size.
Could you suggest me a way how to do such thing?

Try this ( i think you have some typo )
<img alt="image from user home" src="data:image/png;base64,${requestScope.image}">
Also use this site: http://www.askapache.com/online-tools/base64-image-converter/ to make sure that your output Base64 code is correct.

There's an example of ImageAction that serves image from the file system. It's called
Struts 2 dynamic image example.
Instead of base64 encoding/decoding which increases the content length two times and slows down page loading you can use the action that returnes image bytes from the file. It could be a database, in this way it should fetch bytes from Blob.
In your <img> tag that is using src attribute can contain the URL to the action that returns response with a header Content-Type: image/jpeg and bytes written to the body.
This is the code of the ImageAction:
#Result(type = "stream", params = {"contentType", "${type}"})
public class ImageAction extends ActionSupport implements ServletRequestAware {
byte[] imageInByte = null;
String imageId;
private HttpServletRequest servletRequest;
private final static String type = "image/jpeg";
public getInputStream() { return new ByteArrayInputStream(getCustomImageInBytes()); }
public String getType() { return type; }
private String getFilename() {
return this.filename;
}
public String getImageId() {
return imageId;
}
public void setImageId(String imageId) {
this.imageId = imageId;
}
public ImageAction() {
System.out.println("ImageAction");
}
public byte[] getCustomImageInBytes() {
System.out.println("imageId" + imageId);
BufferedImage originalImage;
try {
originalImage = ImageIO.read(getImageFile(this.imageId));
// convert BufferedImage to byte array
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ImageIO.write(originalImage, "jpeg", baos);
baos.flush();
imageInByte = baos.toByteArray();
baos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return imageInByte;
}
private File getImageFile(String imageId) {
String filePath = servletRequest.getSession().getServletContext().getRealPath("/");
File file = new File(filePath + "/Image/", imageId);
System.out.println(file.toString());
return file;
}
#Override
public void setServletRequest(HttpServletRequest request) {
this.servletRequest = request;
}
}
This action supposed to have configuration created by convention-plugin. So it could be used in HTML like this
<img src="<s:url action='Image?imageId=darksouls.jpg' />" alt=""/>

So Alireza Fattahi was right that I had mistakes in my code. The first one is typo in img tag (see answer by Alireza Fattahi), the second one is after reading image to bytes array
byte[] image = ...;
I used
Base64.getEncoder().encode(image);
instead of
Base64.getEncoder().encodeToString(image));
So eventually this method with returning Base64 encoded image works. If there is a better choices - please left comments and answers.

Wicket image component not found on page

I get the following problem when trying to display a list of items. For each item, I have to display an image which is dynamically loaded via a Wicket WebResource. The items are loaded step by step — 50 at a time — upon user scrolling, using an Ajax scroll.
[ERROR] 2011-04-19 09:58:18,000 btpool0-1 org.apache.wicket.RequestCycle.logRuntimeException (host=, request=, site=):
org.apache.wicket.WicketRuntimeException: component documentList:scroller:batchElem:666:content:item:3:batchItemContent:linkToPreview:imageThumbnail not found on page com.webapp.document.pages.DocumentListPage[id = 1]
listener interface = [RequestListenerInterface name=IResourceListener, method=public abstract void org.apache.wicket.IResourceListener.onResourceRequested()]
org.apache.wicket.protocol.http.request.InvalidUrlException: org.apache.wicket.WicketRuntimeException: component documentList:scroller:batchElem:666:content:item:3:batchItemContent:linkToPreview:imageThumbnail
not found on page com.webapp.document.pages.DocumentListPage[id = 1] listener interface = [RequestListenerInterface name=IResourceListener, method=public abstract void org.apache.wicket.IResourceListener.onResourceRequested()]
at org.apache.wicket.protocol.http.WebRequestCycleProcessor.resolve(WebRequestCycleProcessor.java:262)
at org.apache.wicket.RequestCycle.step(RequestCycle.java:1310)
at org.apache.wicket.RequestCycle.steps(RequestCycle.java:1428)
at org.apache.wicket.RequestCycle.request(RequestCycle.java:545)
at org.apache.wicket.protocol.http.WicketFilter.doGet(WicketFilter.java:479)
at org.apache.wicket.protocol.http.WicketFilter$$EnhancerByGuice$$51619816.CGLIB$doGet$6()
at org.apache.wicket.protocol.http.WicketFilter$$EnhancerByGuice$$51619816$$FastClassByGuice$$6d42bf5d.invoke()
at com.google.inject.internal.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
at com.google.inject.internal.InterceptorStackCallback$InterceptedMethodInvocation.proceed(InterceptorStackCallback.java:64)
at com.freiheit.monitoring.PerformanceMonitoringMethodInterceptor.invoke(PerformanceMonitoringMethodInterceptor.java:115)
at com.google.inject.internal.InterceptorStackCallback$InterceptedMethodInvocation.proceed(InterceptorStackCallback.java:64)
at com.google.inject.internal.InterceptorStackCallback.intercept(InterceptorStackCallback.java:44)
at org.apache.wicket.protocol.http.WicketFilter$$EnhancerByGuice$$51619816.doGet()
at org.apache.wicket.protocol.http.WicketFilter.doFilter(WicketFilter.java:312)
at org.apache.wicket.protocol.http.WicketFilter$$EnhancerByGuice$$51619816.CGLIB$doFilter$4()
How can this problem be solved?
Here is the part of the code responsible for adding the image:
previewLink.add(createThumbnailSmall("imageThumbnail", documentModel));
in
createThumbnailSmall(final String id, final IModel<BaseDocument> documentModel) {
// thumbnailResource is an object that contains the path of the image
if (thumbnailResource != null) {
final WebResource resource = getWebResource(thumbnailResource);
final Image image = new Image(id, resource);
return image;
}
return new InvisibleContainer(id);
}
WebResource getWebResource(final DocumentResource documentResource) {
return new WebResource() {
private static final long serialVersionUID = 1L;
#Override
public IResourceStream getResourceStream() {
return new BaseStreamResource(documentResource);
}
};
}
where BaseStreamResource is the following:
public class BaseStreamResource extends AbstractResourceStream {
private InputStream _fileInputStream = null;
private DocumentResource _resource = null;
public BaseStreamResource(final DocumentResource documentResource) {
_resource = documentResource;
}
#Override
public InputStream getInputStream() throws ResourceStreamNotFoundException {
if (_fileInputStream == null) {
try {
if (_resource == null) {
throw new ResourceStreamNotFoundException("Resource was null");
}
_fileInputStream = _resource.getFileInputStream();
} catch (final ResourceNotAvailableException ex) {
throw new ResourceStreamNotFoundException(ex);
}
}
return _fileInputStream;
}
In HTML:
<a wicket:id="linkToPreview" href="#">
<img wicket:id="imageThumbnail" alt="Attachment"></img></a>

The code added hasn't really added any clues for me, but maybe I can help narrow it down a bit anyway.
The stacktrace includes a reference to com.webapp.document.pages.DocumentListPage, which is likely calling some of the code you've posted. The error indicates a bad url, so debugging into that class, adding debug prints, and looking at the values of any field containing a url might be worthwhile.
It might even help to modify the code in DocumentListPage (maybe temporarily for debugging) to catch org.apache.wicket.protocol.http.request.InvalidUrlException and adding debugging prints specifically when the exception is caught.
This isn't really an answer, but it's too big for a comment, and maybe it'll help you get closer to an answer.

The following solution solved the problem:
- extend WebResource class
- add extended class as a resource to application shared resources
Ex:
public class MyWebResource extends WebResource {
final ValueMap map = new ValueMap();
#Override
public IResourceStream getResourceStream() {
String fileName = getFileName();
File file = new File(basePath, fileName);
if (!file.exists()) {
LOG.error("File does not exist: " + file);
throw new IllegalStateException("File does not exist: " + file);
}
return new FileResourceStream(file);
}
public final void addResource() {
Application.get().getSharedResources().add(getClass().getName(), this);
}
protected String getFileName() {
return getParameters().getString("id");
}
public final String urlFor(final String fileName) {
final ResourceReference resourceReference = new ResourceReference(getClass().getName());
final String encodedValue = WicketURLEncoder.QUERY_INSTANCE.encode(fileName);
map.add("id", encodedValue);
final CharSequence result = RequestCycle.get().urlFor(resourceReference, map);
if (result == null) {
throw new IllegalStateException("The resource was not added! "
+ "In your Application class add the following line:"
+ "MyConcreteResource.INSTANCE.addResource()");
}
String absoluteUrl = RequestUtils.toAbsolutePath(result.toString());
return absoluteUrl;
}
}
In Application class, in init(), I have added MyWebResource to shared resources:
public void init() {
...
new MyWebResource().addResource();
...
}