java-8 Archives - Page 6 of 11

Default interface methods are only supported starting with Android 7.0 (Nougat)

I upgraded to Android Studio 3.1 and I’m getting the following error: Default interface methods are only supported starting with Android N (–min-api ...

May 14, 2022
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Functional style of Java 8’s Optional.ifPresent and if-not-Present?

In Java 8, I want to do something to an Optional object if it is present, and do another thing if it is ...

May 13, 2022
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Uses for Optional

Having been using Java 8 now for 6+ months or so, I’m pretty happy with the new API changes. One area I’m still ...

May 13, 2022
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Maven is not working in Java 8 when Javadoc tags are incomplete

Since I use Maven I have been able to build and install in my local repository projects that have incomplete Javadoc tags (for ...

May 13, 2022
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Should Java 8 getters return optional type?

Optional type introduced in Java 8 is a new thing for many developers. Is a getter method returning Optional<Foo> type in place of ...

May 13, 2022
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Ignore duplicates when producing map using streams

Map<String, String> phoneBook = people.stream() .collect(toMap(Person::getName, Person::getAddress)); I get java.lang.IllegalStateException: Duplicate key when a duplicated element is found. Is it possible to ignore ...

May 12, 2022
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How can I throw CHECKED exceptions from inside Java 8 streams?

How can I throw CHECKED exceptions from inside Java 8 streams/lambdas? In other words, I want to make code like this compile: public ...

May 12, 2022
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Calculate days between two Dates in Java 8

I know there are lots of questions on SO about how to get Dates in Java, but I want an example using new ...

May 12, 2022
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Why should one use Objects.requireNonNull()?

I have noted that many Java 8 methods in Oracle JDK use Objects.requireNonNull(), which internally throws NullPointerException if the given object (argument) is ...

May 12, 2022
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Java 8: Difference between two LocalDateTime in multiple units

I am trying to calculate the difference between two LocalDateTime. The output needs to be of the format y years m months d ...

May 11, 2022
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