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Java 8 optional: ifPresent return object orElseThrow exception

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花落未央
花落未央 2020-12-03 09:17

I\'m trying to make something like this:

 private String getStringIfObjectIsPresent(Optional object){
        object.ifPresent(() ->{
               


        
      
      
      

        

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                 醉梦人生 
              
              
    
                
                   醉梦人生
                                             
                
                
                (楼主)
            
              
                  
    
                2020-12-03 09:56
              
    

            
    
            
    
              
              

    Two options here:
    


    Replace ifPresent with map and use Function instead of Consumer
    


    private String getStringIfObjectIsPresent(Optional object) {
    return object
            .map(obj -> {
                String result = "result";
                //some logic with result and return it
                return result;
            })
            .orElseThrow(MyCustomException::new);
}



    Use isPresent:
    


    private String getStringIfObjectIsPresent(Optional object) {
    if (object.isPresent()) {
        String result = "result";
        //some logic with result and return it
        return result;
    } else {
        throw new MyCustomException();
    }
}

    
    
             
    
                                                        
    
            
            
    
              
                
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