https://www.graalvm.org/ 
final class com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache extends com.oracle.truffle.polyglot.PolyglotSourceCache$Cache
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache
  super_class: com.oracle.truffle.polyglot.PolyglotSourceCache$Cache
{
  private final java.util.concurrent.ConcurrentHashMap<com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey, com.oracle.truffle.api.CallTarget> sourceCache;
    descriptor: Ljava/util/concurrent/ConcurrentHashMap;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/util/concurrent/ConcurrentHashMap<Lcom/oracle/truffle/polyglot/PolyglotSourceCache$SourceKey;Lcom/oracle/truffle/api/CallTarget;>;

  private void <init>();
    descriptor: ()V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
         0: .line 176
            aload 0 /* this */
            invokespecial com.oracle.truffle.polyglot.PolyglotSourceCache$Cache.<init>:()V
         1: .line 178
            aload 0 /* this */
            new java.util.concurrent.ConcurrentHashMap
            dup
            invokespecial java.util.concurrent.ConcurrentHashMap.<init>:()V
            putfield com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache.sourceCache:Ljava/util/concurrent/ConcurrentHashMap;
         2: .line 176
            return
        end local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lcom/oracle/truffle/polyglot/PolyglotSourceCache$StrongCache;

  com.oracle.truffle.api.CallTarget lookup(com.oracle.truffle.polyglot.PolyglotLanguageContext, com.oracle.truffle.api.source.Source, java.lang.String[], boolean);
    descriptor: (Lcom/oracle/truffle/polyglot/PolyglotLanguageContext;Lcom/oracle/truffle/api/source/Source;[Ljava/lang/String;Z)Lcom/oracle/truffle/api/CallTarget;
    flags: (0x0000) 
    Code:
      stack=4, locals=8, args_size=5
        start local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
        start local 1 // com.oracle.truffle.polyglot.PolyglotLanguageContext context
        start local 2 // com.oracle.truffle.api.source.Source source
        start local 3 // java.lang.String[] argumentNames
        start local 4 // boolean parse
         0: .line 182
            new com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey
            dup
            aload 2 /* source */
            aload 3 /* argumentNames */
            invokespecial com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey.<init>:(Ljava/lang/Object;[Ljava/lang/String;)V
            astore 5 /* key */
        start local 5 // com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey key
         1: .line 183
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache.sourceCache:Ljava/util/concurrent/ConcurrentHashMap;
            aload 5 /* key */
            invokevirtual java.util.concurrent.ConcurrentHashMap.get:(Ljava/lang/Object;)Ljava/lang/Object;
            checkcast com.oracle.truffle.api.CallTarget
            astore 6 /* target */
        start local 6 // com.oracle.truffle.api.CallTarget target
         2: .line 184
            aload 6 /* target */
            ifnonnull 7
            iload 4 /* parse */
            ifeq 7
         3: .line 185
            aload 1 /* context */
            aload 3 /* argumentNames */
            aload 2 /* source */
            invokestatic com.oracle.truffle.polyglot.PolyglotSourceCache.parseImpl:(Lcom/oracle/truffle/polyglot/PolyglotLanguageContext;[Ljava/lang/String;Lcom/oracle/truffle/api/source/Source;)Lcom/oracle/truffle/api/CallTarget;
            astore 6 /* target */
         4: .line 186
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache.sourceCache:Ljava/util/concurrent/ConcurrentHashMap;
            aload 5 /* key */
            aload 6 /* target */
            invokevirtual java.util.concurrent.ConcurrentHashMap.putIfAbsent:(Ljava/lang/Object;Ljava/lang/Object;)Ljava/lang/Object;
            checkcast com.oracle.truffle.api.CallTarget
            astore 7 /* prevTarget */
        start local 7 // com.oracle.truffle.api.CallTarget prevTarget
         5: .line 187
            aload 7 /* prevTarget */
            ifnull 7
         6: .line 188
            aload 7 /* prevTarget */
            astore 6 /* target */
        end local 7 // com.oracle.truffle.api.CallTarget prevTarget
         7: .line 191
      StackMap locals: com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey com.oracle.truffle.api.CallTarget
      StackMap stack:
            aload 6 /* target */
            areturn
        end local 6 // com.oracle.truffle.api.CallTarget target
        end local 5 // com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey key
        end local 4 // boolean parse
        end local 3 // java.lang.String[] argumentNames
        end local 2 // com.oracle.truffle.api.source.Source source
        end local 1 // com.oracle.truffle.polyglot.PolyglotLanguageContext context
        end local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
      LocalVariableTable:
        Start  End  Slot           Name  Signature
            0    8     0           this  Lcom/oracle/truffle/polyglot/PolyglotSourceCache$StrongCache;
            0    8     1        context  Lcom/oracle/truffle/polyglot/PolyglotLanguageContext;
            0    8     2         source  Lcom/oracle/truffle/api/source/Source;
            0    8     3  argumentNames  [Ljava/lang/String;
            0    8     4          parse  Z
            1    8     5            key  Lcom/oracle/truffle/polyglot/PolyglotSourceCache$SourceKey;
            2    8     6         target  Lcom/oracle/truffle/api/CallTarget;
            5    7     7     prevTarget  Lcom/oracle/truffle/api/CallTarget;
    MethodParameters:
               Name  Flags
      context        
      source         
      argumentNames  
      parse          

  boolean isEmpty();
    descriptor: ()Z
    flags: (0x0000) 
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
         0: .line 196
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache.sourceCache:Ljava/util/concurrent/ConcurrentHashMap;
            invokevirtual java.util.concurrent.ConcurrentHashMap.isEmpty:()Z
            ireturn
        end local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/polyglot/PolyglotSourceCache$StrongCache;

  void listSources(com.oracle.truffle.polyglot.PolyglotLanguageInstance, java.util.Collection<org.graalvm.polyglot.Source>);
    descriptor: (Lcom/oracle/truffle/polyglot/PolyglotLanguageInstance;Ljava/util/Collection;)V
    flags: (0x0000) 
    Code:
      stack=3, locals=6, args_size=3
        start local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
        start local 1 // com.oracle.truffle.polyglot.PolyglotLanguageInstance language
        start local 2 // java.util.Collection sources
         0: .line 201
            aload 1 /* language */
            invokevirtual com.oracle.truffle.polyglot.PolyglotLanguageInstance.getImpl:()Lcom/oracle/truffle/polyglot/PolyglotImpl;
            astore 3 /* polygot */
        start local 3 // com.oracle.truffle.polyglot.PolyglotImpl polygot
         1: .line 202
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache.sourceCache:Ljava/util/concurrent/ConcurrentHashMap;
            invokevirtual java.util.concurrent.ConcurrentHashMap.keySet:()Ljava/util/concurrent/ConcurrentHashMap$KeySetView;
            invokevirtual java.util.concurrent.ConcurrentHashMap$KeySetView.iterator:()Ljava/util/Iterator;
            astore 5
            goto 4
      StackMap locals: com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache com.oracle.truffle.polyglot.PolyglotLanguageInstance java.util.Collection com.oracle.truffle.polyglot.PolyglotImpl top java.util.Iterator
      StackMap stack:
         2: aload 5
            invokeinterface java.util.Iterator.next:()Ljava/lang/Object;
            checkcast com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey
            astore 4 /* key */
        start local 4 // com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey key
         3: .line 203
            aload 2 /* sources */
            aload 3 /* polygot */
            aload 4 /* key */
            getfield com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey.key:Ljava/lang/Object;
            checkcast com.oracle.truffle.api.source.Source
            invokevirtual com.oracle.truffle.polyglot.PolyglotImpl.getOrCreatePolyglotSource:(Lcom/oracle/truffle/api/source/Source;)Lorg/graalvm/polyglot/Source;
            invokeinterface java.util.Collection.add:(Ljava/lang/Object;)Z
            pop
        end local 4 // com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey key
         4: .line 202
      StackMap locals:
      StackMap stack:
            aload 5
            invokeinterface java.util.Iterator.hasNext:()Z
            ifne 2
         5: .line 205
            return
        end local 3 // com.oracle.truffle.polyglot.PolyglotImpl polygot
        end local 2 // java.util.Collection sources
        end local 1 // com.oracle.truffle.polyglot.PolyglotLanguageInstance language
        end local 0 // com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    6     0      this  Lcom/oracle/truffle/polyglot/PolyglotSourceCache$StrongCache;
            0    6     1  language  Lcom/oracle/truffle/polyglot/PolyglotLanguageInstance;
            0    6     2   sources  Ljava/util/Collection<Lorg/graalvm/polyglot/Source;>;
            1    6     3   polygot  Lcom/oracle/truffle/polyglot/PolyglotImpl;
            3    4     4       key  Lcom/oracle/truffle/polyglot/PolyglotSourceCache$SourceKey;
    Signature: (Lcom/oracle/truffle/polyglot/PolyglotLanguageInstance;Ljava/util/Collection<Lorg/graalvm/polyglot/Source;>;)V
    MethodParameters:
          Name  Flags
      language  
      sources   
}
SourceFile: "PolyglotSourceCache.java"
NestHost: com.oracle.truffle.polyglot.PolyglotSourceCache
InnerClasses:
  private abstract Cache = com.oracle.truffle.polyglot.PolyglotSourceCache$Cache of com.oracle.truffle.polyglot.PolyglotSourceCache
  private final SourceKey = com.oracle.truffle.polyglot.PolyglotSourceCache$SourceKey of com.oracle.truffle.polyglot.PolyglotSourceCache
  private final StrongCache = com.oracle.truffle.polyglot.PolyglotSourceCache$StrongCache of com.oracle.truffle.polyglot.PolyglotSourceCache
  public KeySetView = java.util.concurrent.ConcurrentHashMap$KeySetView of java.util.concurrent.ConcurrentHashMap