空行削除

LambdaSample.java

import java.util.Arrays;
import java.util.List;
import java.util.function.UnaryOperator;

public class LambdaSample {

    public static void main(String[] args) {
        List<String> list = Arrays.asList("Tokyo", "Kanagawa", "Saitama", "Chiba", "Gunma", "Tochigi", "Ibaraki");

        // SE7以前の書き方
        before(list);

        // SE8以降（ラムダ式）の書き方
        after(list);

    }

    private static void before(List<String> list) {
        list.replaceAll(new UnaryOperator<String>() {
            @Override
            public String apply(String s) {
                return s.toUpperCase();
            }
        });

        System.out.println(list);
    }

    private static void after(List<String> list) {
        list.replaceAll(s -> s.toUpperCase());
        System.out.println(list);
    }

}