[ https://issues.jboss.org/browse/JBWEB-311?page=com.atlassian.jira.plugin.... ] Aaron Ogburn updated JBWEB-311: ------------------------------- Description: JspConfig init isn't thread safe and can cause the following ConcurrentModificationException: {code} java.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372) at java.util.AbstractList$Itr.next(AbstractList.java:343) at org.apache.jasper.compiler.JspConfig.findJspProperty(JspConfig.java:303) at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:112) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:333) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:313) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:300) at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:312) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:322) {code} Issue occurs like so: 1) thread a starts JspConfig.init/proccessWebDotXml 2) thread b starts JspConfig.init/proccessWebDotXml 3) thread a finishes JspConfig.init/proccessWebDotXml and then calls JspConfig.findJspProperty 4) thread b sets the jspProperties vector before thread a gets an iterator of it 5) thread b modifies the jspProperties vector, causing the ConcurrentModificationException in thread a was: JspConfig init isn't thread safe and can cause the following ConcurrentModificationException: {code} java.util.ConcurrentModificationException at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:372) at java.util.AbstractList$Itr.next(AbstractList.java:343) at org.apache.jasper.compiler.JspConfig.findJspProperty(JspConfig.java:303) at org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:112) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:333) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:313) at org.apache.jasper.compiler.Compiler.compile(Compiler.java:300) at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:585) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:312) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:322) {code} -- This message was sent by Atlassian JIRA (v6.3.11#6341)