字符数组转换及数字求和 java8 lambda表达式 demo

public static void main(String[] args) throws IllegalAccessException {
		//字符串转换为数字且每个加上100，输出。
		String[] ids = {"100","12","23","45","68","78","99","200"};
		List<Integer> list = Stream.of(ids).map(x -> Integer.valueOf(x) + 100).collect(Collectors.toList());
		//编译循环
		list.stream().forEach(x -> System.out.print(x+","));

		//按1.8编译
		Integer[] array = { 1, 2, 3, 4, 5 };
		Stream.of(array).forEach(System.out::println);  	// prints 1, 2, 3, ...
//		Arrays.stream(array).forEach(System.out::println);

		//Mysql in 查询参数
		String str = Stream.of(array).map(x -> "'"+String.valueOf(x)+"'").collect(Collectors.joining(",","(",")"));
		System.out.println("str="+str);

		//求和
//		Integer sum = Stream.of(array).mapToInt(x -> x).sum();
//		Integer sum = Stream.of(array).mapToInt(Integer::valueOf).sum();
		Integer sum = Stream.of(array).mapToInt(x -> Integer.valueOf(x)).sum();
		System.out.println("sum="+sum);

	}