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Java 8: How do I work with exception throwing methods in streams?

Suppose I have a class and a method class A { void foo() throws Exception() { ... } } Now I would like ...

May 28, 2022
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Java 8 – Best way to transform a list: map or foreach?

I have a list myListToParse where I want to filter the elements and apply a method on each element, and add the result ...

May 25, 2022
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How to use a Java8 lambda to sort a stream in reverse order?

I’m using java lambda to sort a list. how can I sort it in a reverse way? I saw this post, but I ...

May 23, 2022
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Why are Java Streams once-off?

Unlike C#’s IEnumerable, where an execution pipeline can be executed as many times as we want, in Java a stream can be ‘iterated’ ...

May 23, 2022
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Using streams to convert a list of objects into a string obtained from the toString method

There are a lot of useful new things in Java 8. E.g., I can iterate with a stream over a list of objects ...

May 21, 2022
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Java8: HashMap to HashMap using Stream / Map-Reduce / Collector

I know how to “transform” a simple Java List from Y -> Z, i.e.: List<String> x; List<Integer> y = x.stream() .map(s -> Integer.parseInt(s)) ...

May 21, 2022
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Why does Iterable not provide stream() and parallelStream() methods?

I am wondering why the Iterable interface does not provide the stream() and parallelStream() methods. Consider the following class: public class Hand implements ...

May 21, 2022
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Using Java 8’s Optional with Stream::flatMap

The new Java 8 stream framework and friends make for some very concise Java code, but I have come across a seemingly-simple situation ...

May 18, 2022
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Filter Java Stream to 1 and only 1 element

I am trying to use Java 8 Streams to find elements in a LinkedList. I want to guarantee, however, that there is one ...

May 18, 2022
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Java 8 method references: provide a Supplier capable of supplying a parameterized result

I’d like to use java.util.Optional.orElseThrow() with an Exception type that asks for a constructor parameter. Something like this: .orElseThrow(MyException::new(someArgument)) // obviously NOT working ...

May 17, 2022
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