https://www.graalvm.org/ 
final class com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext extends com.oracle.truffle.polyglot.PolyglotReferences$AbstractContextReference
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext
  super_class: com.oracle.truffle.polyglot.PolyglotReferences$AbstractContextReference
{
  private final com.oracle.truffle.api.TruffleLanguage$ContextReference<java.lang.Object> singleContextReference;
    descriptor: Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lcom/oracle/truffle/api/TruffleLanguage$ContextReference<Ljava/lang/Object;>;

  private final com.oracle.truffle.api.TruffleLanguage$ContextReference<java.lang.Object> fallbackReference;
    descriptor: Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lcom/oracle/truffle/api/TruffleLanguage$ContextReference<Ljava/lang/Object;>;

  private final com.oracle.truffle.api.Assumption validIf0;
    descriptor: Lcom/oracle/truffle/api/Assumption;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final com.oracle.truffle.api.Assumption validIf1;
    descriptor: Lcom/oracle/truffle/api/Assumption;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  static final boolean $assertionsDisabled;
    descriptor: Z
    flags: (0x1018) ACC_STATIC, ACC_FINAL, ACC_SYNTHETIC

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 310
            ldc Lcom/oracle/truffle/polyglot/PolyglotReferences;
            invokevirtual java.lang.Class.desiredAssertionStatus:()Z
            ifne 1
            iconst_1
            goto 2
      StackMap locals:
      StackMap stack:
         1: iconst_0
      StackMap locals:
      StackMap stack: int
         2: putstatic com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.$assertionsDisabled:Z
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  void <init>(com.oracle.truffle.polyglot.PolyglotLanguage, com.oracle.truffle.api.Assumption, com.oracle.truffle.api.Assumption, com.oracle.truffle.api.TruffleLanguage$ContextReference<java.lang.Object>, );
    descriptor: (Lcom/oracle/truffle/polyglot/PolyglotLanguage;Lcom/oracle/truffle/api/Assumption;Lcom/oracle/truffle/api/Assumption;Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;Z)V
    flags: (0x0000) 
    Code:
      stack=3, locals=6, args_size=6
        start local 0 // com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext this
        start local 1 // com.oracle.truffle.polyglot.PolyglotLanguage language
        start local 2 // com.oracle.truffle.api.Assumption validIf0
        start local 3 // com.oracle.truffle.api.Assumption validIf1
        start local 4 // com.oracle.truffle.api.TruffleLanguage$ContextReference fallback
        start local 5 // boolean strong
         0: .line 317
            aload 0 /* this */
            invokespecial com.oracle.truffle.polyglot.PolyglotReferences$AbstractContextReference.<init>:()V
         1: .line 318
            aload 0 /* this */
            aload 2 /* validIf0 */
            putfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.validIf0:Lcom/oracle/truffle/api/Assumption;
         2: .line 319
            aload 0 /* this */
            aload 3 /* validIf1 */
            putfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.validIf1:Lcom/oracle/truffle/api/Assumption;
         3: .line 320
            aload 0 /* this */
            aload 1 /* language */
            iload 5 /* strong */
            invokestatic com.oracle.truffle.polyglot.PolyglotReferences.createAlwaysSingleContext:(Lcom/oracle/truffle/polyglot/PolyglotLanguage;Z)Lcom/oracle/truffle/polyglot/PolyglotReferences$AbstractContextReference;
            putfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.singleContextReference:Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
         4: .line 321
            aload 0 /* this */
            aload 4 /* fallback */
            putfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.fallbackReference:Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
         5: .line 322
            return
        end local 5 // boolean strong
        end local 4 // com.oracle.truffle.api.TruffleLanguage$ContextReference fallback
        end local 3 // com.oracle.truffle.api.Assumption validIf1
        end local 2 // com.oracle.truffle.api.Assumption validIf0
        end local 1 // com.oracle.truffle.polyglot.PolyglotLanguage language
        end local 0 // com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    6     0      this  Lcom/oracle/truffle/polyglot/PolyglotReferences$AssumeSingleContext;
            0    6     1  language  Lcom/oracle/truffle/polyglot/PolyglotLanguage;
            0    6     2  validIf0  Lcom/oracle/truffle/api/Assumption;
            0    6     3  validIf1  Lcom/oracle/truffle/api/Assumption;
            0    6     4  fallback  Lcom/oracle/truffle/api/TruffleLanguage$ContextReference<Ljava/lang/Object;>;
            0    6     5    strong  Z
    Signature: (Lcom/oracle/truffle/polyglot/PolyglotLanguage;Lcom/oracle/truffle/api/Assumption;Lcom/oracle/truffle/api/Assumption;Lcom/oracle/truffle/api/TruffleLanguage$ContextReference<Ljava/lang/Object;>;Z)V
    MethodParameters:
          Name  Flags
      language  
      validIf0  
      validIf1  
      fallback  
      strong    

  public java.lang.Object get();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=1
        start local 0 // com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext this
         0: .line 327
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.validIf0:Lcom/oracle/truffle/api/Assumption;
            ifnull 1
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.validIf0:Lcom/oracle/truffle/api/Assumption;
            invokeinterface com.oracle.truffle.api.Assumption.isValid:()Z
            ifeq 4
      StackMap locals:
      StackMap stack:
         1: aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.validIf1:Lcom/oracle/truffle/api/Assumption;
            ifnull 2
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.validIf1:Lcom/oracle/truffle/api/Assumption;
            invokeinterface com.oracle.truffle.api.Assumption.isValid:()Z
            ifeq 4
         2: .line 328
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.singleContextReference:Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
            invokevirtual com.oracle.truffle.api.TruffleLanguage$ContextReference.get:()Ljava/lang/Object;
            astore 1 /* context */
        start local 1 // java.lang.Object context
         3: .line 329
            goto 5
        end local 1 // java.lang.Object context
         4: .line 330
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.fallbackReference:Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
            invokevirtual com.oracle.truffle.api.TruffleLanguage$ContextReference.get:()Ljava/lang/Object;
            astore 1 /* context */
        start local 1 // java.lang.Object context
         5: .line 332
      StackMap locals: java.lang.Object
      StackMap stack:
            getstatic com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.$assertionsDisabled:Z
            ifne 6
            aload 0 /* this */
            getfield com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext.fallbackReference:Lcom/oracle/truffle/api/TruffleLanguage$ContextReference;
            invokevirtual com.oracle.truffle.api.TruffleLanguage$ContextReference.get:()Ljava/lang/Object;
            aload 1 /* context */
            if_acmpeq 6
            new java.lang.AssertionError
            dup
            invokespecial java.lang.AssertionError.<init>:()V
            athrow
         6: .line 333
      StackMap locals:
      StackMap stack:
            aload 1 /* context */
            areturn
        end local 1 // java.lang.Object context
        end local 0 // com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    7     0     this  Lcom/oracle/truffle/polyglot/PolyglotReferences$AssumeSingleContext;
            3    4     1  context  Ljava/lang/Object;
            5    7     1  context  Ljava/lang/Object;
}
SourceFile: "PolyglotReferences.java"
NestHost: com.oracle.truffle.polyglot.PolyglotReferences
InnerClasses:
  public abstract ContextReference = com.oracle.truffle.api.TruffleLanguage$ContextReference of com.oracle.truffle.api.TruffleLanguage
  abstract AbstractContextReference = com.oracle.truffle.polyglot.PolyglotReferences$AbstractContextReference of com.oracle.truffle.polyglot.PolyglotReferences
  private final AssumeSingleContext = com.oracle.truffle.polyglot.PolyglotReferences$AssumeSingleContext of com.oracle.truffle.polyglot.PolyglotReferences