Multiple null checks in Java 8

You may do it like so:

String s = Stream.of(str1, str2, str3)
    .filter(Objects::nonNull)
    .findFirst()
    .orElse(str4);

How about ternary conditional operator?

String s = 
    str1 != null ? str1 : 
    str2 != null ? str2 : 
    str3 != null ? str3 : str4
;

You can also use a loop:

String[] strings = {str1, str2, str3, str4};
for(String str : strings) {
    s = str;
    if(s != null) break;
}

Current answers are nice but you really should put that in a utility method:

public static Optional<String> firstNonNull(String... strings) {
    return Arrays.stream(strings)
            .filter(Objects::nonNull)
            .findFirst();
}

That method has been in my Util class for years, makes code much cleaner:

String s = firstNonNull(str1, str2, str3).orElse(str4);

You can even make it generic:

@SafeVarargs
public static <T> Optional<T> firstNonNull(T... objects) {
    return Arrays.stream(objects)
            .filter(Objects::nonNull)
            .findFirst();
}

// Use
Student student = firstNonNull(student1, student2, student3).orElseGet(Student::new);

I use a helper function, something like

T firstNonNull<T>(T v0, T... vs) {
  if(v0 != null)
    return v0;
  for(T x : vs) {
    if (x != null) 
      return x;
  }
  return null;
}

Then this kind of code can be written as

String s = firstNonNull(str1, str2, str3, str4);