For loop to Java 8 stream foreach()

See English answers > break or return from Java 8 stream for each? 11

If any value does not exist, it immediately returns false

public boolean exists(List<String> keys) {
     for(String key: keys) {
         boolean exists = service.existsByKey(key);
         if(!exists) return false;
      }
        return true;
}

I tried to change it to Java 8 foreach, but it didn't work as expected

keys.stream().forEach(k -> {
    boolean exists = service.existsByKey(k);
    if(!exists) return false;
});

Did I miss anything? Why not enter (! Exists) staetment in foreach()?

Solution

The return statement in your foreach method will be ignored

Try using

boolean exists = key.stream().allMatch(k -> service.existsByKey(k));