Caught exception still showing stack trace

Question

I have a piece of code which attempts to draw some data out of a JPEG. The line that actually gets the data will raise a com.sun.image.codec.jpeg.TruncatedFileException: Premature end of input file, if you have a corrupt JPEG. If I put the code in a "try" block, and try to catch com.sun.image.codec.jpeg.TruncatedFileException, the catch never gets executed. But if I do a generic catch by just catching Exception, the catch block DOES get executed. HOWEVER... Even though the catch block is executed, and I have a line that says "System.out.println("Found a problem");" or something like that, Java still outputs a stack trace as well. This is making me think that maybe it is throwing 2 exceptions? But if I put another try block around it, it still does the same thing.... Here is a snippet of my code, followed by the stack trace.
RenderedImage meanImage = JAI.create("mean", pb, null);
double[] mean;
try {
mean = (double[])meanImage.getProperty("mean");
} catch (Exception e) {
System.out.println("Caught in getProperty.");
return;
NOTE: The line "mean = (double[])meanImage.getProperty("mean");
is the one throwing the exception. And I've tried the catch block with and without the return statement.
Here is the stack trace...
Corrupt JPEG data: premature end of data segment
com.sun.image.codec.jpeg.TruncatedFileException: Premature end of input file
at sun.awt.image.codec.JPEGImageDecoderImpl.readJPEGStream(Native Method)
at sun.awt.image.codec.JPEGImageDecoderImpl.decodeAsBufferedImage(JPEGImageDecoderImpl.java:210)
at com.sun.media.jai.codecimpl.JPEGImage.<init>(JPEGImageDecoder.java:112)
at com.sun.media.jai.codecimpl.JPEGImageDecoder.decodeAsRenderedImage(JPEGImageDecoder.java:51)
at com.sun.media.jai.opimage.CodecRIFUtil.create(CodecRIFUtil.java:89)
at com.sun.media.jai.opimage.JPEGRIF.create(JPEGRIF.java:52)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:130)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1669)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:481)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:340)
at com.sun.media.jai.opimage.StreamRIF.create(StreamRIF.java:104)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:130)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1669)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:481)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:340)
at com.sun.media.jai.opimage.FileLoadRIF.create(FileLoadRIF.java:109)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:130)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1669)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:481)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:340)
at javax.media.jai.RenderedOp.createInstance(RenderedOp.java:805)
at javax.media.jai.RenderedOp.createRendering(RenderedOp.java:853)
at javax.media.jai.RenderedOp.getRendering(RenderedOp.java:874)
at javax.media.jai.RenderedOp$1.getPropertyNames(RenderedOp.java:1777)
at javax.media.jai.PropertyEnvironment.mapDefaults(PropertyEnvironment.java:280)
at javax.media.jai.PropertyEnvironment.getPropertyNames(PropertyEnvironment.java:135)
at javax.media.jai.WritablePropertySourceImpl.addProperties(WritablePropertySourceImpl.java:306)
at javax.media.jai.RenderedOp.createPropertySource(RenderedOp.java:1803)
at javax.media.jai.RenderedOp.getPropertyNames(RenderedOp.java:1837)
at javax.media.jai.PropertyEnvironment.hashNames(PropertyEnvironment.java:319)
at javax.media.jai.PropertyEnvironment.<init>(PropertyEnvironment.java:125)
at javax.media.jai.DescriptorCache.getPropertySource(DescriptorCache.java:1198)
at javax.media.jai.OperationRegistry.getPropertySource(OperationRegistry.java:1941)
at javax.media.jai.ThreadSafeOperationRegistry.getPropertySource(ThreadSafeOperationRegistry.java:595)
at javax.media.jai.OperationRegistry.getPropertySource(OperationRegistry.java:1980)
at javax.media.jai.ThreadSafeOperationRegistry.getPropertySource(ThreadSafeOperationRegistry.java:608)
at javax.media.jai.OperationNodeSupport.getPropertySource(OperationNodeSupport.java:624)
at javax.media.jai.RenderedOp.createPropertySource(RenderedOp.java:1800)
at javax.media.jai.RenderedOp.getProperty(RenderedOp.java:1924)
at plugins.medianEvaluator$Evaluate.Caught in getProperty.
Name: /home/jimdrewes/TEST.JPG Color: java.awt.Color[r=0,g=0,b=0]
<init>(medianEvaluator.java:74)
at plugins.medianEvaluator$1.construct(medianEvaluator.java:41)
at plugins.SwingWorker$2.run(SwingWorker.java:110)
at java.lang.Thread.run(Thread.java:536)
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:130)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1669)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:481)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:340)
at com.sun.media.jai.opimage.FileLoadRIF.create(FileLoadRIF.java:109)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at javax.media.jai.FactoryCache.invoke(FactoryCache.java:130)
at javax.media.jai.OperationRegistry.invokeFactory(OperationRegistry.java:1669)
at javax.media.jai.ThreadSafeOperationRegistry.invokeFactory(ThreadSafeOperationRegistry.java:481)
at javax.media.jai.registry.RIFRegistry.create(RIFRegistry.java:340)
at javax.media.jai.RenderedOp.createInstance(RenderedOp.java:805)
at javax.media.jai.RenderedOp.createRendering(RenderedOp.java:853)
at javax.media.jai.RenderedOp.getRendering(RenderedOp.java:874)
at javax.media.jai.RenderedOp$1.getPropertyNames(RenderedOp.java:1777)
at javax.media.jai.PropertyEnvironment.mapDefaults(PropertyEnvironment.java:280)
at javax.media.jai.PropertyEnvironment.getPropertyNames(PropertyEnvironment.java:135)
at javax.media.jai.WritablePropertySourceImpl.addProperties(WritablePropertySourceImpl.java:306)
at javax.media.jai.RenderedOp.createPropertySource(RenderedOp.java:1803)
at javax.media.jai.RenderedOp.getPropertyNames(RenderedOp.java:1837)
at javax.media.jai.PropertyEnvironment.hashNames(PropertyEnvironment.java:319)
at javax.media.jai.PropertyEnvironment.<init>(PropertyEnvironment.java:125)
at javax.media.jai.DescriptorCache.getPropertySource(DescriptorCache.java:1198)
at javax.media.jai.OperationRegistry.getPropertySource(OperationRegistry.java:1941)
at javax.media.jai.ThreadSafeOperationRegistry.getPropertySource(ThreadSafeOperationRegistry.java:595)
at javax.media.jai.OperationRegistry.getPropertySource(OperationRegistry.java:1980)
at javax.media.jai.ThreadSafeOperationRegistry.getPropertySource(ThreadSafeOperationRegistry.java:608)
at javax.media.jai.OperationNodeSupport.getPropertySource(OperationNodeSupport.java:624)
at javax.media.jai.RenderedOp.createPropertySource(RenderedOp.java:1800)
at javax.media.jai.RenderedOp.getProperty(RenderedOp.java:1924)
at plugins.medianEvaluator$Evaluate.<init>(medianEvaluator.java:74)
at plugins.medianEvaluator$1.construct(medianEvaluator.java:41)
at plugins.SwingWorker$2.run(SwingWorker.java:110)
at java.lang.Thread.run(Thread.java:536)
Caused by: java.lang.RuntimeException: Unable to process image stream, incorrect format.
at com.sun.media.jai.codecimpl.JPEGImage.<init>(JPEGImageDecoder.java:114)
at com.sun.media.jai.codecimpl.JPEGImageDecoder.decodeAsRenderedImage(JPEGImageDecoder.java:51)
at com.sun.media.jai.codec.ImageDecoderImpl.decodeAsRenderedImage(ImageDecoderImpl.java:148)
at com.sun.media.jai.opimage.StreamRIF.create(StreamRIF.java:135)
... 40 more
I'm using Forte as my development environment, and JAI to do imaging stuff.
Any help would be great.
Thanks,
-Jim Drewes
www.jimdrewes.com

Answer 1

Actually, if you look at the stack trace close enoughI told you I didn't read the stack trace... I never will read anything that you don't bother simplifying down, perhaps since *you* knew where this was you could have pointed it out...
Because your line is being printed in the middle of the stack trace is a *BIG* hint that the exception you are catching is not the one that is printing the stack trace.
So its almost like its catching an error
after it raises a DIFFERENT not-caught error.Which is eactly what I told you... And by the position of your ESystem.out line there is also an (several?) un-caught error after your caught error.
I tried putting all of those create
statements in their own try blocks,
but it still gave me the same error.Are you sure its the same exceptio, and not other exceptions.
I also stuck in a MediaTracker yesterday...
The tracker comes back just fine,
with no errors on the image being
loaded. But when the data gets drawn
out, it raises this error again.Maybe have a google for image loading and java.awt.image.ImageObserver for some more clues.