android/guava/src/com/google/common/base/Predicates.java
public static <T> Predicate<T> equalTo(@NullableDecl T target) {
    return (target == null) ? Predicates.<T>isNull() : new IsEqualToPredicate<T>(target);
  }
public static <T> Predicate<T> equalTo(@NullableDecl T target) {
    return (target == null) ? Predicates.<T>isNull() : new IsEqualToPredicate<T>(target);
  }
Returns a predicate that evaluates to {@code true} if the object being tested {@code equals()}
the given target or both are null.