2
我試圖從我的數據庫中以二進制數據的形式提取圖像，並將其插入到Jasper Reports報告中。從數據庫中顯示圖像。獲取net.sf.jasperreports.engine.JRException：圖像讀取失敗
使用Jaspersoft Studio，我在我的字段中讀取並將其類型更改爲java.awt.Image。 然後，我的圖像元素添加到我的報告，並更改表達式爲$ {Attr1_icon} 當我嘗試編譯，我得到：
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)
導致此異常來自這裏JRJdk14ImageReader的源代碼。 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;
}
因此，您可以看到圖像爲空。但我不明白爲什麼。我已驗證數據實際存在。如果將數據類型更改爲字符串並將其添加到普通文本字段，則會打印二進制數據。所以，我不認爲它是空的，因爲傳入的數據是空的。
從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.
所以我想有沒有註冊的ImageReader？我怎麼能通過Jaspersoft Studio修復這樣的問題？
編輯：我已經嘗試使用java.io.InputStream類類型建議here但這會導致相同的錯誤。有點。最大的區別在於，在Jaspersoft Studio中，如果出現錯誤，可以將圖像設置爲空白。如果我使用java.awt.Image，那麼這個設置什麼都不做。我仍然收到錯誤，報告沒有建立。如果我使用java.io.InputStream，則報告生成，但圖像爲空。如果我打開了錯誤報告，我得到了類似的堆棧跟蹤，但它是不完全一樣：
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)
雖然，你可以看到，根本原因仍然來自JRJdk14ImageReader.java線73
其他一些可能有用的信息：
數據作爲LONG BINARY（使用Sybase）存儲在數據庫中。
圖像是base64編碼的。
這個問題阻止我完成我的項目，截止日期接近相當快。任何幫助都會很棒。
編輯2：我更新了我的版本Jaspersoft Studio從5.5到5.6，但沒有做任何事情。
同樣，對於表達式我嘗試了javax.imageio.ImageIO.read（$ F {Attr1_icon}） 這實際上不會產生任何錯誤，但圖像是空白的。