Convert Optional to boolean in functional style

Question

I just wanted to return a boolean from an Optional object by doing a check on the getProductType() on the ProductDetails object as shown below:

public boolean isElectronicProduct(String productName) {
    Optional<ProductDetails> optProductDetails = findProductDetails(productName);
    if(optProductDetails.isPresent()) {
        return optProductDetails.get().getProductType() == ProductType.ELECTRONICS;
    }
    return false;
}

Intellij complains stating that the above code can be replaced in functional style, is there really any way to simplify the above Optional object and return a boolean?

Answer 1

Change this:

if(optProductDetails.isPresent()) {
    return optProductDetails.get().getProductType() == ProductType.ELECTRONICS;
}
return false;

To:

return optProductDetails
      .filter(prodDet -> prodDet.getProductType() == ProductType.ELECTRONICS)  // Optional<ProductDetails> which match the criteria
      .isPresent();   // boolean

You can read more about functional-style operations on Optional values at: https://docs.oracle.com/javase/8/docs/api/java/util/Optional.html