Java 8 forEach打印带有索引

实现思路:
    使用intstream.range生成指定范围的数据
	使用mapToObj转换为键值对的模式
	输出信息即可

package com.java265.java8;
 
import java.util.list;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
 
public class JavaArrayWithIndex {
 
    public static void main(String[] args) {
 
        String[] names = {"Java", "Node", "JavaScript", "C#", "Python"};
 
        List<String> collect = IntStream.range(0, names.length)
                .mapToObj(index -> index + ":" + names[index])
                .collect(Collectors.toList());
 
        collect.forEach(System.out::println);
    }
}

方式2:List转换为Map,使用Map.size作为索引

<R> R collect(Supplier<R> supplier,
                  BiConsumer<R, ? super T> accumulator,
                  BiConsumer<R, R> combiner);



package com.java265.java8;
 
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
 
public class JavaListWithIndex {
 
    public static void main(String[] args) {
 
        List<String> list = Arrays.asList("Java", "Node", "JavaScript", "C#", "Python");
 
        HashMap<Integer, String> collect = list
                .stream()
                .collect(HashMap<Integer, String>::new,
                        (map, streamValue) -> map.put(map.size(), streamValue),
                        (map, map2) -> {
                        });
        collect.forEach((k, v) -> System.out.println(k + ":" + v));
    }
}