In Java, I have something like this:
String[] firstname = { "name1", "name2", "name3" };
String[] lastname = { "lastname1", "lastname2", "lastname3" };
and the result I need would be something like this:
String[] newArray = {"name1 lastname1", "name2 lastname2", "name3 lastname3"};
combining one by one name lastname into String[] newArray assuming the lengths are the same.
The Java 7 and earlier way might be to just use a loop and iterate over all first and last names:
String[] fullname = new String[firstname.length];
for (int i=0; i < firstname.length; ++i) {
fullname[i] = firstname[i] + " " + lastname[i];
}
You can use Java 8's Stream API and index both arrays with an stream of integers.
String[] firstname = { "name1", "name2", "name3" };
String[] lastname = { "lastname1", "lastname2", "lastname3" };
String[] newArray = IntStream.range(0, firstname.length).boxed()
.map(i -> firstname[i] + " " + lastname[i]).toArray(String[]::new);
System.out.println(Arrays.toString(newArray));
This yields
[name1 lastname1, name2 lastname2, name3 lastname3]
This answers assumes, that the length of lastname is at least the length of firstname, but OP already stated that.