In my project I found this exception org.eclipse.jdt.internal.compiler.classfmt.ClassFormatException. How to resolve it?

Question

org.eclipse.jdt.internal.compiler.classfmt.ClassFormatException
    at org.eclipse.jdt.internal.compiler.classfmt.ClassFileReader.<init>(ClassFileReader.java:372)
    at org.apache.jasper.compiler.JDTCompiler$1.findType(JDTCompiler.java:232)
    at org.apache.jasper.compiler.JDTCompiler$1.findType(JDTCompiler.java:188)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.askForType(LookupEnvironment.java:113)
    at org.eclipse.jdt.internal.compiler.lookup.UnresolvedReferenceBinding.resolve(UnresolvedReferenceBinding.java:49)
    at org.eclipse.jdt.internal.compiler.lookup.BinaryTypeBinding.resolveType(BinaryTypeBinding.java:122)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.getTypeFromTypeSignature(LookupEnvironment.java:1335)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.getTypeFromVariantTypeSignature(LookupEnvironment.java:1391)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.getTypeArgumentsFromSignature(LookupEnvironment.java:1172)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.getTypeFromTypeSignature(LookupEnvironment.java:1340)
    at org.eclipse.jdt.internal.compiler.lookup.BinaryTypeBinding.createMethod(BinaryTypeBinding.java:550)
    at org.eclipse.jdt.internal.compiler.lookup.BinaryTypeBinding.createMethods(BinaryTypeBinding.java:630)
    at org.eclipse.jdt.internal.compiler.lookup.BinaryTypeBinding.cachePartsFrom(BinaryTypeBinding.java:365)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.createBinaryTypeFrom(LookupEnvironment.java:688)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.createBinaryTypeFrom(LookupEnvironment.java:667)
    at org.eclipse.jdt.internal.compiler.Compiler.accept(Compiler.java:296)
    at org.eclipse.jdt.internal.compiler.lookup.LookupEnvironment.askForType(LookupEnvironment.java:118)
    at org.eclipse.jdt.internal.compiler.lookup.UnresolvedReferenceBinding.resolve(UnresolvedReferenceBinding.java:49)
    at org.eclipse.jdt.internal.compiler.lookup.BinaryTypeBinding.resolveType(BinaryTypeBinding.java:122)
    at org.eclipse.jdt.internal.compiler.lookup.PackageBinding.getTypeOrPackage(PackageBinding.java:168)
    at org.eclipse.jdt.internal.compiler.lookup.Scope.getPackage(Scope.java:2379)
    at org.eclipse.jdt.internal.compiler.ast.ParameterizedQualifiedTypeReference.internalResolveLeafType(ParameterizedQualifiedTypeReference.java:138)
    at org.eclipse.jdt.internal.compiler.ast.ParameterizedQualifiedTypeReference.internalResolveType(ParameterizedQualifiedTypeReference.java:132)
    at org.eclipse.jdt.internal.compiler.ast.ParameterizedQualifiedTypeReference.resolveType(ParameterizedQualifiedTypeReference.java:351)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.resolveTypeFor(SourceTypeBinding.java:1374)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.fields(SourceTypeBinding.java:699)
    at org.eclipse.jdt.internal.compiler.lookup.SourceTypeBinding.faultInTypesForFieldsAndMethods(SourceTypeBinding.java:677)
    at org.eclipse.jdt.internal.compiler.lookup.CompilationUnitScope.faultInTypes(CompilationUnitScope.java:469)
    at org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:756)
    at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:468)
    at org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:459)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:378)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:353)
    at org.apache.jasper.compiler.Compiler.compile(Compiler.java:340)
    at org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:646)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:931)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

I am using Apache Tomcat/7.0.33, eclipse-jee-kepler-SR1-RC3-win32

Hyalite

looks like a tomcat problem. what tomcat version, eclipse version and jvm version are you using? – Placia

Tomcat now uses the bundled Eclipse compiler to compile JSPs - it's not related to the IDE being used, per se. The question I do have is: What version of the JDK are you using? – Halftrack

Answer 1

Thanks much for the tips! Ran into same ClassFormatException error on Tomcat 6.0.20 and JDK1.8. Replaced the jasper-jdt.jar with ecj-4.2.2.jar and all the JSPs compiling/working again.

Epode

This should be comment – Lelandleler

Solved the problem for me ! – Americanize

add this jar ecj-4.2.2.jar file into your tomcat_install_folder/lib/ecj-4.2.2.jar and stop tomcat server and delete or rename the old version of the ecj like old_ecj-3.6.jar and start your tomcat server it work for me without touching the jasper-jdt.jar bcz it was not there in the lib folder for me – Theorize

Solved my problem, didn't noticed I changed the JRE_HOME path. – Palisade

Phew, this one saved my day! – Alec

This just made some of our tests a lot easier. No need to migrate old servers to Tomcat 9 just before decommissionning them, and that's good. – Ramonaramonda

Answer 2

The problem is related to ecj version (ecj-3.7.2.jar), you have to use a more recent version of tomcat compatible with jdk8 (apache-tomcat-7.0.68 works fine for me )

Groceryman

Answer 3

I hope the following steps will solve your problem.

1) Stop the tomcat.

2) Download ecj-4.2.2.jar in this link

3) Copy ecj-4.2.2.jar under tomcat's lib folder (example - C:\apache-tomcat-6.0.36\lib).

4) Rename ecj-3.7.2.jar to old_ecj-3.7.2.jar.

5) Start the tomcat.

Cariole

Answer 4

If you use maven and jdk8 to start tomcat7, make sure that the version of the tomcat7-maven-plugin is at least 2.2

Estaminet

Answer 5

Remove existing localhost servers and add new server. This will solve your problem.

Normally

Answer 6

Check Your Tomcat Version.If your tomcat version 7.0.29 and below then Remove your Old Tomcat and Download latest one . And run the project https://tomcat.apache.org/download-90.cgi

Charil

Answer 7

If you is using java 8 maybe you should update your eclipse version.

Eclipse doc

Kaja

Answer 8

Going by the information in the stack trace, it seems that there is a compilation problem with the built in eclipse compiler which it uses rather than javac. All the Luna builds of Eclipse have support for jdk 8 but as you have mentioned that you are using Eclipse Kepler, you would have to download a feature patch from the eclipse community itself in order to support jdk 8.

Meanwhile you can you use jdk 7 and recompile your project. See if the error goes away. Apart from that the code looks fine to me. I hope it helps. Happy to help.

Rexanne

Answer 9

I had the same problem using Tomcat 6 with Java 8. I solved it by configuring Tomcat to use Java 7 instead of 8: Add export JAVA_HOME=/usr/lib/jvm/java-7-oracle in your {tomcat-home}/bin/catalina.sh or your custom startup script.

Mousey

Answer 10

Note that 1. We cannot update the version of ECJ included with Tomcat 6, as Tomcat 6 must be able to run on Java 1.5, but current ECJ releases require minimum of Java 6.

2. You may replace ecj-*.jar with a later version that you may download from http://www.eclipse.org/

See archives of Tomcat Users mailing list, and ask on the mailing list if you have questions. (Bugzilla is not a support forum).

4. Tomcat can be configured to use Java javac compiler instead of Eclipse

Dosage

Answer 11

i also faced same problem after searching many article i could found this solution

which version of Tomcat you are using.

Second, for Java 8 you have to use a version of Eclipse ECJ compiler that supports Java 8.

The "ClassFormatException" probably means that your version of ECJ does not know about Java 8 at all.

change the jre new version to old version because it doesn't support to this tomcat version

Dosage

Answer 12

This Problem is caused due to compatibility issue with jdk, tomcat and Eclipse. For resolving this problem use jdk ver 1.8 with apache tomcat 8.0 and updated Eclipse Mars 2.0.

I have the same problem with Apache Tomcat 7.0.

Reconfigure all and your problem will be solved.

Rockhampton

Answer 13

If you got here using something a little more modern (I was updating a project from java8 to java17), upgrading jasper, itext and poi from the old version to the new version did the trick for me.

Carolincarolina