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bad return type in lambda expression

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情深已故
情深已故 2021-02-05 14:00

The following code compiles fine in IntelliJ and Eclipse, but the JDK compiler 1.8.0_25 complains. First, the code.

import java.util.function.Predicate;

public
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  • 无人及你
    无人及你 (楼主)
    2021-02-05 14:17

    includes Object, which isn't a Boolean. ie 

    MyPredicate

    Could be a 

    MyPredicate



    and you can't return an Object as a boolean.
    


    Try changing your lambda to:
    


    MyStream. create().filter(b -> Boolean.TRUE.equals(b));

    


    which will compile and execute without error not matter the type of the stream, but will return true for elements that are true Boolean values.
    
    
    
             
    
                                                        
    
            
            
    
              
                
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