Java: convert List to a String

Question

JavaScript has Array.join()

js>[\"Bill\",\"Bob\",\"Steve\"].join(\" and \")
Bill and Bob and Steve

Does Java have anything

Answer 1

Google's Guava API also has .join(), although (as should be obvious with the other replies), Apache Commons is pretty much the standard here.

Answer 2

Three possibilities in Java 8:

List<String> list = Arrays.asList("Alice", "Bob", "Charlie")

String result = String.join(" and ", list);

result = list.stream().collect(Collectors.joining(" and "));

result = list.stream().reduce((t, u) -> t + " and " + u).orElse("");

Answer 3

Not out of the box, but many libraries have similar:

Commons Lang:

org.apache.commons.lang.StringUtils.join(list, conjunction);

Spring:

org.springframework.util.StringUtils.collectionToDelimitedString(list, conjunction);

Answer 4

With a java 8 collector, this can be done with the following code:

Arrays.asList("Bill", "Bob", "Steve").stream()
.collect(Collectors.joining(" and "));

Also, the simplest solution in java 8:

String.join(" and ", "Bill", "Bob", "Steve");

or

String.join(" and ", Arrays.asList("Bill", "Bob", "Steve"));

Answer 5

On Android you could use TextUtils class.

TextUtils.join(" and ", names);

Answer 6

Java 8 solution with java.util.StringJoiner

Java 8 has got a StringJoiner class. But you still need to write a bit of boilerplate, because it's Java.

StringJoiner sj = new StringJoiner(" and ", "" , "");
String[] names = {"Bill", "Bob", "Steve"};
for (String name : names) {
   sj.add(name);
}
System.out.println(sj);