This FAQ came from community discussion and feedback. This user installed SkyWalking Java agent on WebSphere 7.0.0.11 and ibm jdk 1.8_20160719 and 1.7.0_20150407, and had following error logs
WARN 2019-05-09 17:01:35:905 SkywalkingAgent-1-GRPCChannelManager-0 ProtectiveShieldMatcher : Byte-buddy occurs exception when match type. java.lang.IllegalStateException: Cannot resolve type description for java.security.PrivilegedAction at org.apache.skywalking.apm.dependencies.net.bytebuddy.pool.TypePool$Resolution$Illegal.resolve(TypePool.java:144) at org.apache.skywalking.apm.dependencies.net.bytebuddy.pool.TypePool$Default$WithLazyResolution$LazyTypeDescription.delegate(TypePool.java:1392) at org.apache.skywalking.apm.dependencies.net.bytebuddy.description.type.TypeDescription$AbstractBase$OfSimpleType$WithDelegation.getInterfaces(TypeDescription.java:8016) at org.apache.skywalking.apm.dependencies.net.bytebuddy.description.type.TypeDescription$Generic$OfNonGenericType.getInterfaces(TypeDescription.java:3621) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.HasSuperTypeMatcher.hasInterface(HasSuperTypeMatcher.java:53) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.HasSuperTypeMatcher.hasInterface(HasSuperTypeMatcher.java:54) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.HasSuperTypeMatcher.matches(HasSuperTypeMatcher.java:38) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.HasSuperTypeMatcher.matches(HasSuperTypeMatcher.java:15) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.ElementMatcher$Junction$Conjunction.matches(ElementMatcher.java:107) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.ElementMatcher$Junction$Disjunction.matches(ElementMatcher.java:147) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.ElementMatcher$Junction$Disjunction.matches(ElementMatcher.java:147) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.ElementMatcher$Junction$Disjunction.matches(ElementMatcher.java:147) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.ElementMatcher$Junction$Disjunction.matches(ElementMatcher.java:147) at org.apache.skywalking.apm.dependencies.net.bytebuddy.matcher.ElementMatcher$Junction$Disjunction.matches(ElementMatcher.java:147) ...
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