"AOT tooling classes" are classes that are used only in the AOT training/assembly phases and are not needed in production runs.

These classes should be excluded to save footprint. With the upcoming JDK-8325147 (Ahead-of-Time Method Profiling), profiles for the tooling classes should be also be excluded, or else the JVM may compile many methods at start-up which aren't going to be used.

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For example, when running HelloWorld with -XX:AOTMode=record, these classes are loaded only by java/lang/invoke/GenerateJLIClassesHelper to generate lambda form holder classes customized for this application. Excluding these classes shrinks the AOT cache from 9,981,952 to 9,682,944 bytes.

java/lang/classfile/attribute/ExceptionsAttribute
java/lang/classfile/CodeBuilder$1
java/lang/invoke/ClassSpecializer$Factory$1
java/lang/invoke/ClassSpecializer$Factory$1$1
java/lang/invoke/ClassSpecializer$Factory$1$1Var
java/lang/invoke/ClassSpecializer$Factory$1$2
java/lang/invoke/ClassSpecializer$Factory$1$3
java/lang/invoke/ClassSpecializer$Factory$1$4
java/lang/invoke/ClassSpecializer$Factory$1$5
java/lang/invoke/ClassSpecializer$Factory$1$5$1
java/lang/invoke/GenerateJLIClassesHelper
java/lang/invoke/GenerateJLIClassesHelper$HolderClassBuilder
java/lang/invoke/MethodHandleImpl$2
java/lang/invoke/MethodHandleImpl$IntrinsicMethodHandle
java/util/ArrayList$Itr
java/util/ArrayList$SubList
java/util/Arrays$ArrayList
java/util/NavigableMap
java/util/NavigableSet
java/util/SequencedMap
java/util/SequencedSet
java/util/SortedMap
java/util/SortedSet
java/util/Spliterators$ArraySpliterator
java/util/stream/ForEachOps
java/util/stream/ForEachOps$ForEachOp
java/util/stream/ForEachOps$ForEachOp$OfRef
java/util/stream/TerminalSink
java/util/TreeMap
java/util/TreeMap$Entry
java/util/TreeMap$EntryIterator
java/util/TreeMap$EntrySet
java/util/TreeMap$KeyIterator
java/util/TreeMap$KeySet
java/util/TreeMap$PrivateEntryIterator
java/util/TreeMap$ValueIterator
java/util/TreeMap$Values
java/util/TreeSet
jdk/internal/classfile/impl/AbstractAttributeMapper$ExceptionsMapper
jdk/internal/classfile/impl/UnboundAttribute$UnboundExceptionsAttribute