I have used predicates before to filter collections as follows:
JavaScript
x
package com.byhiras.predicate;
import com.byhiras.domain.Bid;
import com.byhiras.domain.User;
import com.google.common.base.Predicate;
/**
* List of predicates pertinent to User
*/
public class UserPredicate {
/**
* Is a bid made by a particular user?
*
* @param usr
* @return
*/
public static Predicate<Bid> isBidByUser(User usr) {
return p -> p.getUser().getName().equals(usr.getName());
}
}
For the above I used Java 8 and the latest Guava library. However I’m working on an assignment where I am restricted to Java 6 and version 13.0.1 of Guava with zero chance of getting them to update their maven repo.
I am struggling to get a similar type of predicate done in Java 6 as the use of lambda expressions is not allowed.
I would appreciate any help to port this code to Java 6. Thanks
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Answer
The typical, pre-Java-8 way of doing things looks like
JavaScript
public static Predicate<Bid> isBidByUser(final User usr) {
return new Predicate<Bid>() {
@Override public boolean apply(Bid p) {
return p.getUser().getName().equals(usr.getName());
}
};
}