Using Java 8 to convert a list of objects into a string obtained from the toString() method

Question

There are a lot of useful new things in Java 8. E.g., I can iterate with a stream over a list of objects and then sum the values from a specific field of the Object

Answer 1

List list = Arrays.asList("One", "Two", "Three");
    list.stream()
            .reduce("", org.apache.commons.lang3.StringUtils::join);

Or

List list = Arrays.asList("One", "Two", "Three");
        list.stream()
                .reduce("", (s1,s2)->s1+s2);

This approach allows you also build a string result from a list of objects Example

List list = Arrays.asList(w1, w2, w2);
        list.stream()
                .map(w->w.getStringValue)
                .reduce("", org.apache.commons.lang3.StringUtils::join);

Here the reduce function allows you to have some initial value to which you want to append new string Example:

 List errors = Arrays.asList("er1", "er2", "er3");
            list.stream()
                    .reduce("Found next errors:", (s1,s2)->s1+s2);