McAnder McAnder - 11 months ago 65
Java Question

Java 8 Lambda stack bleed

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class StackBleed {
public static int check(String s) {
if (s.equals("lambda")) {
throw new IllegalArgumentException();
return s.length();

@SuppressWarnings({ "rawtypes", "unchecked" })
public static void main(String[] args) {
// List lengths = new ArrayList();
List<String> argList = Arrays.asList(args);

Stream lengths2 = name) -> check(name));

So I was checking out this article and wrote similar class, but JDK 8 approach didn't yield expected exception. I was wondering if they have changed something in JDK 8u5?

Answer Source

You're only calling a non-terminal operation on the stream. So your code doesn't consume the data from the stream. All it does is saying: "when a terminal operation will be called, you'll have to map the strings using the check() method".


List<Integer> transformed = name) -> check(name)).collect(Collectors.toList());

for example, and then the call to collect(), which is a terminal operation, will trigger the iteration on the stream elements and the transformation of its elements.