I've got four variables and I want to check if any one of them is null. I can do
if (null == a || null == b || null == c || null == d) {
...
}
but what I really want is
if (anyNull(a, b, c, d)) {
...
}
but I don't want to write it myself. Does this function exist in any common Java library? I checked Commons Lang and didn't see it. It should use varargs to take any number of arguments.
I don't know if it's in commons, but it takes about ten seconds to write:
public static boolean anyNull(Object... objs) {
for (Object obj : objs)
if (obj == null)
return true;
return false;
}
The best you can do with the Java library is, I think:
if (asList(a, b, c, d).contains(null)) {
List.of(a, b, c, d).contains(null) will never retain false - it will NPE.You asked in the comments where to put the static helper, I suggest
public class All {
public static final boolean notNull(Object... all) { ... }
}
and then use the qualified name for call, such as
assert All.notNull(a, b, c, d);
Same can then be done with a class Any and methods like isNull.
In Java 8 you can do it in even more elegant way:
if (Stream.of(a, b, c, d).anyMatch(Objects::isNull)) { ... }
or you can extract it to a method:
public static boolean anyNull(Object... objects) {
return Stream.of(objects).anyMatch(Objects::isNull);
}
and then use it in your code like this:
if (anyNull(a, b, c, d)) { ... }
