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import java.util.function.Consumer;
import java.util.function.Function;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;
class ExtensionMethodFunctional {
public void test() {
String test = "test";
test = ExtensionMethodFunctional.Extensions.map(test, s -> ExtensionMethodFunctional.Extensions.reverse(s));
ExtensionMethodFunctional.Extensions.consume(test, s -> System.out.println("1: " + s), s -> System.out.println("2: " + s));
ExtensionMethodFunctional.Extensions.consume(test, System.out::println, System.out::println);
ExtensionMethodFunctional.Extensions.toList(Stream.of("a", "b", "c").map(String::toUpperCase));
List<Integer> i2 = ExtensionMethodFunctional.Extensions.toList2(Stream.of("a", "b", "c").map(String::toUpperCase));
}
static class Extensions {
public static <T, R> R map(T value, Function<T, R> mapper) {
return mapper.apply(value);
}
public static String reverse(String string) {
return new StringBuilder(string).reverse().toString();
}
@SafeVarargs
public static <T> void consume(T o, Consumer<T>... consumer) {
for (int i = 0; i < consumer.length; i++) {
consumer[i].accept(o);
}
}
public static <T> List<T> toList(Stream<T> stream) {
return (List<T>) stream.collect(Collectors.toList());
}
public static <T, U> List<U> toList2(Stream<T> stream) {
return null;
}
}
}
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