Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
509 views
in Technique[技术] by (71.8m points)

java - Show image from database. Getting net.sf.jasperreports.engine.JRException: Image read failed

I'm trying to pull an image as binary data from my database and insert it into a Jasper Reports report.

Using Jaspersoft Studio, I read in my field and change it's type to java.awt.Image. Then, I add an image element to my report and change the expression to ${Attr1_icon} When I try to compile, I get:

net.sf.jasperreports.engine.JRException: net.sf.jasperreports.engine.JRException: Unable to get value for field 'Attr1_icon' of class 'java.awt.Image'
at com.jaspersoft.studio.editor.preview.view.control.ReportControler.fillReport(ReportControler.java:482)
at com.jaspersoft.studio.editor.preview.view.control.ReportControler.access$18(ReportControler.java:457)
at com.jaspersoft.studio.editor.preview.view.control.ReportControler$4.run(ReportControler.java:347)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)
Caused by: net.sf.jasperreports.engine.JRException: Unable to get value for field 'Attr1_icon' of class 'java.awt.Image'
at net.sf.jasperreports.engine.JRResultSetDataSource.getFieldValue(JRResultSetDataSource.java:319)
at net.sf.jasperreports.engine.fill.JRFillDataset.setOldValues(JRFillDataset.java:1356)
at net.sf.jasperreports.engine.fill.JRFillDataset.next(JRFillDataset.java:1257)
at net.sf.jasperreports.engine.fill.JRFillDataset.next(JRFillDataset.java:1233)
at net.sf.jasperreports.engine.fill.JRBaseFiller.next(JRBaseFiller.java:1577)
at net.sf.jasperreports.engine.fill.JRVerticalFiller.fillReport(JRVerticalFiller.java:149)
at net.sf.jasperreports.engine.fill.JRBaseFiller.fill(JRBaseFiller.java:932)
at net.sf.jasperreports.engine.fill.BaseFillHandle$ReportFiller.run(BaseFillHandle.java:120)
at java.lang.Thread.run(Unknown Source)
Caused by: net.sf.jasperreports.engine.JRException: Image read failed.
at net.sf.jasperreports.engine.util.JRJdk14ImageReader.readImage(JRJdk14ImageReader.java:73)
at net.sf.jasperreports.engine.util.JRImageLoader.loadAwtImageFromBytes(JRImageLoader.java:167)
at net.sf.jasperreports.engine.JRResultSetDataSource.getFieldValue(JRResultSetDataSource.java:309)
Caused by: net.sf.jasperreports.engine.JRException: Image read failed.
at net.sf.jasperreports.engine.util.JRJdk14ImageReader.readImage(JRJdk14ImageReader.java:73)
at net.sf.jasperreports.engine.util.JRImageLoader.loadAwtImageFromBytes(JRImageLoader.java:167)
at net.sf.jasperreports.engine.JRResultSetDataSource.getFieldValue(JRResultSetDataSource.java:309)

The source code that caused this exception comes from here in JRJdk14ImageReader.java:

public Image readImage(byte[] bytes) throws JRException {
    InputStream bais = new ByteArrayInputStream(bytes);

    Image image = null;
    try {
        image = ImageIO.read(bais);
    } catch (Exception e) {
        throw new JRException(e);
    } finally {
        try {
            bais.close();
        } catch (IOException e) {
        }
    }

    if (image == null) {
        throw new JRException("Image read failed."); // Line 73
    }

    return image;
}

So, you can see that the image is null. But I don't understand why. I've verified that the data is actually there. If I change the data type to a string and add it to a normal text field, it prints the binary data. So, I don't think it's null because the passed in data is null.

From the Javadoc:

Returns a BufferedImage as the result of decoding a supplied InputStream with an
ImageReader chosen automatically from among those currently registered. The InputStream
is wrapped in an ImageInputStream. If no registered ImageReader claims to be able to
read the resulting stream, null is returned.

So I guess there is no registered ImageReader? How could I fix something like that through Jaspersoft Studio?

EDIT: I've tried using java.io.InputStream for the class type as suggested here but that results in the same error. Kind of. A big difference is that, in Jaspersoft Studio, you can set the image to show up blank if there is an error. If I use java.awt.Image, then this setting does nothing. I still get an error and the report doesn't build. If I use java.io.InputStream, the report does build, but the image is blank. If I switch on the error reporting, I get a similar stack trace, but it's not quite the same:

net.sf.jasperreports.engine.JRRuntimeException: net.sf.jasperreports.engine.JRException: Image read failed.
at net.sf.jasperreports.engine.export.draw.PrintDrawVisitor.visit(PrintDrawVisitor.java:143)
at net.sf.jasperreports.engine.export.draw.PrintDrawVisitor.visit(PrintDrawVisitor.java:1)
at net.sf.jasperreports.engine.fill.JRTemplatePrintImage.accept(JRTemplatePrintImage.java:451)
at net.sf.jasperreports.engine.export.draw.FrameDrawer.draw(FrameDrawer.java:251)
at net.sf.jasperreports.engine.export.draw.FrameDrawer.draw(FrameDrawer.java:199)
at net.sf.jasperreports.engine.export.JRGraphics2DExporter.exportPage(JRGraphics2DExporter.java:273)
at net.sf.jasperreports.engine.export.JRGraphics2DExporter.exportReportToGraphics2D(JRGraphics2DExporter.java:246)
at net.sf.jasperreports.engine.export.JRGraphics2DExporter.exportReport(JRGraphics2DExporter.java:184)
at net.sf.jasperreports.eclipse.viewer.ViewerCanvas.renderPage(ViewerCanvas.java:369)
at net.sf.jasperreports.eclipse.viewer.ViewerCanvas.refresh(ViewerCanvas.java:344)
at net.sf.jasperreports.eclipse.viewer.ViewerCanvas$2.viewerStateChanged(ViewerCanvas.java:118)
at net.sf.jasperreports.eclipse.viewer.ReportViewer.fireViewerModelChanged(ReportViewer.java:383)
at net.sf.jasperreports.eclipse.viewer.ReportViewer.setPageIndex(ReportViewer.java:297)
at com.jaspersoft.studio.editor.preview.view.report.swt.SWTViewer.setJRPRint(SWTViewer.java:125)
at com.jaspersoft.studio.editor.preview.view.report.swt.SWTViewer.setJRPRint(SWTViewer.java:112)
at com.jaspersoft.studio.editor.preview.PreviewJRPrint.switchRightView(PreviewJRPrint.java:226)
at com.jaspersoft.studio.editor.preview.PreviewContainer.switchRightView(PreviewContainer.java:247)
at com.jaspersoft.studio.editor.preview.PreviewJRPrint$3.switchView(PreviewJRPrint.java:194)
at com.jaspersoft.studio.editor.preview.PreviewJRPrint$1.run(PreviewJRPrint.java:153)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:135)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4144)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3761)
at org.eclipse.ui.internal.Workbench.runEventLoop(Workbench.java:2701)
at org.eclipse.ui.internal.Workbench.runUI(Workbench.java:2665)
at org.eclipse.ui.internal.Workbench.access$4(Workbench.java:2499)
at org.eclipse.ui.internal.Workbench$7.run(Workbench.java:679)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:332)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:668)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:149)
at com.jaspersoft.studio.rcp.intro.Application.start(Application.java:97)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584)
at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
Caused by: net.sf.jasperreports.engine.JRException: Image read failed.
at net.sf.jasperreports.engine.util.JRJdk14ImageReader.readImage(JRJdk14ImageReader.java:73)
at net.sf.jasperreports.engine.util.JRImageLoader.loadAwtImageFromBytes(JRImageLoader.java:167)
at net.sf.jasperreports.engine.JRImageRenderer.getImage(JRImageRenderer.java:407)
at net.sf.jasperreports.engine.JRImageRenderer.getDimension(JRImageRenderer.java:482)
at net.sf.jasperreports.engine.RenderableUtil.getOnErrorRendererForDimension(RenderableUtil.java:264)
at net.sf.jasperreports.engine.export.draw.ImageDrawer.draw(ImageDrawer.java:116)
at net.sf.jasperreports.engine.export.draw.PrintDrawVisitor.visit(PrintDrawVisitor.java:134)

Though, as you can see, the root cause still comes from JRJdk14ImageReader.java line 73.

Some other information that might be useful:

The data is stored in the database as a LONG BINARY (using Sybase).
The image is base64 encoded.

This issue is blocking me from finishing my project, with the deadline approaching pretty fast. Any help would be great.

EDIT 2: I updated my version of Jaspersoft Studio from 5.5 to 5.6, but that did nothing.

As well, for the expression I tried javax.imageio.ImageIO.read($F{Attr1_icon}) This actually does not produce any error, but the image is blank.

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

Even though I posted it in the issue, I completely overlooked the fact that the image was Base64 encoded, meaning it was a string. As is, this value couldn't be used by Jasper, so it had to be decoded. This can be done one of two ways:

Change the expression to:

new java.io.ByteArrayInputStream(javax.xml.DatatypeConverter.parseBase64Binary($F{ImageField}))

or Simply convert the string to binary in the data base. In Sybase, that's the base64_decode function. Once it is converted, you can simply change the type to java.io.InputStream and it'll work.


与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...