Reputation: 751
I have the following the code currently.
Method - parseGreeting()
public GetGreetingNmsObjects parseGreeting(String greetingType, GetGreetingNmsResponse xmlFromNms) {
GetGreetingNmsObjects objectFound = null;
List<GetGreetingNmsObjects> objList = xmlFromNms.getObject();
for (GetGreetingNmsObjects obj : objList) {
List<Attribute> attrs = obj.getAttributes();
Optional<Boolean> found = attrs.stream()
.filter(a -> a.name.equals(GREETING_TYPE))
.map(a -> a.value.equals(greetingType))
.findAny();
if(found.get()) {
objectFound = obj;
break;
}
return objectFound;
}
GetGreetingNmsObjects .java
public class GetGreetingNmsObjects {
List<Attribute> attributeList;
public List<Attribute> getAttributes() {
return attributeList;
}
}
In the above method, is there a way to avoid the for loop and if statement and handle with streams itself?
I tried to use 'flatmap' and get the stream for 'attributesList' but once the match is found, I could not get reference to 'GetGreetingNmsObjects' object.
GetGreetingNmsObjects objectFound = objList.stream()
.flatMap(grt -> grt.getAttributes())
.filter(a -> a.name.equals(GREETING_TYPE))
.map(a -> a.value.equals(greetingType))
????
Upvotes: 5
Views: 1692
Reputation: 298599
Your original code contains a logic error:
Optional<Boolean> found = …
.map(a -> a.value.equals(greetingType))
.findAny();
This will return the result of an arbitrary comparison, in a sequential context, it’s likely the result of the first element.
I’m quite sure that you actually want to know whether there is any matching element, hence, should use
boolean found = …
.anyMatch(a -> a.value.equals(greetingType));
This can be simply used as predicate to find the first element having the matching element:
return xmlFromNms.getObject().stream()
.filter(obj -> obj.getAttributes().stream()
.filter( a -> a.name.equals(GREETING_TYPE))
.anyMatch(a -> a.value.equals(greetingType)))
.findFirst().orElse(null);
Upvotes: 11