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@Nonnull(when = When.UNKNOWN)
@TypeQualifierDefault(value = ElementType.TYPE_USE)
@Retention(value = RetentionPolicy.CLASS)
@UnstableApi
public annotation UnknownNull
    
    
    Annotation for specifying unknown nullness. Useful for clearing the effects of an automatically propagated Nonnull annotation.
  
  
  
    
  
 
  
    
      
      
    
    
      
    
    
  
       
    
    
      
    
  
  
  Content and code samples on this page are subject to the licenses described in the Content License. Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
  Last updated 2025-07-17 UTC.
  
  
  
    
      [[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-07-17 UTC."],[],[]]