[PDFBOX-3015] PDICCBased loadICCProfile() throwing ConcurrentModificationException

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 2.0.0
• Component/s: Rendering
• Environment: Windows 8.1 Pro; java 6-8; tomcat 6-7
• Assignee: Unassigned
• Reporter: Jason Mackin
• Created: 09/Oct/15 17:40
• Updated: 04/Sep/17 16:05
• Resolved: 04/Sep/17 16:05

Description

When running a load test using PDFRenderer's method renderImageWithDPI(pageIndex, 175), I am receiving a ConcurrentModificationException. I only receive this using Java 6-8 and Tomcat 6 or 7 but Tomcat 8 seems to work. I can reproduce this with as little as 4 concurrent threads kicked off at the same time. It only happens the first time the method is called (server startup), after that it works fine.

Here is the stacktrace:

java.util.ConcurrentModificationException
at java.util.Vector$Itr.checkForComodification(Vector.java:1156)
at java.util.Vector$Itr.next(Vector.java:1133)
at sun.java2d.cmm.ProfileDeferralMgr.activateProfiles(ProfileDeferralMgr.java:93)
at java.awt.color.ICC_Profile.getInstance(ICC_Profile.java:775)
at java.awt.color.ICC_Profile.getInstance(ICC_Profile.java:1013)
at org.apache.pdfbox.pdmodel.graphics.color.PDICCBased.loadICCProfile(PDICCBased.java:119)
at org.apache.pdfbox.pdmodel.graphics.color.PDICCBased.<init>(PDICCBased.java:89)
at org.apache.pdfbox.pdmodel.graphics.color.PDColorSpace.create(PDColorSpace.java:162)
at org.apache.pdfbox.pdmodel.PDResources.getColorSpace(PDResources.java:155)
at org.apache.pdfbox.contentstream.operator.color.SetStrokingColorSpace.process(SetStrokingColorSpace.java:41)
at org.apache.pdfbox.contentstream.PDFStreamEngine.processOperator(PDFStreamEngine.java:799)
at org.apache.pdfbox.contentstream.PDFStreamEngine.processStreamOperators(PDFStreamEngine.java:461)
at org.apache.pdfbox.contentstream.PDFStreamEngine.processStream(PDFStreamEngine.java:438)
at org.apache.pdfbox.contentstream.PDFStreamEngine.processPage(PDFStreamEngine.java:149)
at org.apache.pdfbox.rendering.PageDrawer.drawPage(PageDrawer.java:180)
at org.apache.pdfbox.rendering.PDFRenderer.renderPage(PDFRenderer.java:208)
at org.apache.pdfbox.rendering.PDFRenderer.renderImage(PDFRenderer.java:139)
at org.apache.pdfbox.rendering.PDFRenderer.renderImageWithDPI(PDFRenderer.java:80)

Since the problem was with a java class not being synchronized, I added a simple static synchronized method to PDICCBased.java to load the profile and prevent the race condition:

private static synchronized ICC_Profile getICCProfile(InputStream input) throws IOException {
return ICC_Profile.getInstance(input);
}

And call it from the loadICCProfile method:

ICC_Profile profile = PDICCBased.getICCProfile(input);

Issue Links

• duplicates: PDFBOX-3267 Using threads results in different images