org.apache.tomcat.util.bcel.classfile.ClassFormatException: Invalid byte tag in constant pool: 15 - Tomcat 7, JDK incompatibilty? [duplicate]

Question

I tried upgrading to Java 8. When starting our tomcat7 server, with a Java 7-compiled .war file, I get the mysteriously error below.

Should I expect this to work? This post says tomcat 7 should work with 1.6 and up. I can't tell if Tomcat is to blame, or the .war. Switching out different Java versions I get:

• JDK 7.45 installed - works (same version used to compile .war)
• JDK 7.55 installed - fails as below
• JDK 8.05 installed - fails as below

Is tomcat to blame, or the .war?

Caused by: org.apache.tomcat.util.bcel.classfile.ClassFormatException: Invalid byte tag in constant pool: 15
        at org.apache.tomcat.util.bcel.classfile.Constant.readConstant(Constant.java:131)
        at org.apache.tomcat.util.bcel.classfile.ConstantPool.<init>(ConstantPool.java:60)
        at org.apache.tomcat.util.bcel.classfile.ClassParser.readConstantPool(ClassParser.java:209)
        at org.apache.tomcat.util.bcel.classfile.ClassParser.parse(ClassParser.java:119)
        at org.apache.catalina.startup.ContextConfig.processAnnotationsStream(ContextConfig.java:2032)
        at org.apache.catalina.startup.ContextConfig.processAnnotationsJar(ContextConfig.java:1923)
        at org.apache.catalina.startup.ContextConfig.processAnnotationsUrl(ContextConfig.java:1891)
        at org.apache.catalina.startup.ContextConfig.processAnnotations(ContextConfig.java:1877)
        at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1270)
        at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:855)
        at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:345)
        at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
        at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
        at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5161)
        at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)

Answer 1

I was seeing this error with Tomcat 7.0.26.

To answer your question, Tomcat is to blame: https://issues.apache.org/bugzilla/show_bug.cgi?id=53735

Upgrading to version 7.0.53 fixed it for me (according to the linked issue, the fix should be in 7.0.30 and later).