org.apache.tomcat.util.bcel.classfile.ClassFormatException：常量池中无效的字节标记：15

Question

Tomcat成功启动，但在logcatalina.out中，我得到：

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:2049)
    at org.apache.catalina.startup.ContextConfig.processAnnotationsJar(ContextConfig.java:1931)
    at org.apache.catalina.startup.ContextConfig.processAnnotationsUrl(ContextConfig.java:1899)
    at org.apache.catalina.startup.ContextConfig.processAnnotations(ContextConfig.java:1885)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1281)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:855)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:346)
    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:5172)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:899)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:875)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
    at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

会有什么问题？

Answer 1

“官方答案”是Tomcat7运行在Java8上，请参见http://Tomcat.apache.org/whichversion.html（“Java version 6及更高版本”）。

但是，如果启用了注释扫描（web.xml中的metadata-complete=“true”），由于BCEL（不能处理新的Java8字节代码），会出现一些问题。您将得到如下异常（至少在Tomcat 7.0.28中）：

SEVERE: Unable to process Jar entry [jdk/nashorn/internal/objects/NativeString.class] from Jar [jar:file:/usr/lib/jvm/jdk1.8.0_5/jre/lib/ext/nashorn.jar!/] for annotations
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)

如果不使用注释扫描，一切都很好，从7.0.53版开始（更新的编译器支持更好的Java8）。

junit.jar,junit-*.jar,ant-launcher.jar,\
jfxrt.jar,nashorn.jar