I have string like: 

String input = "1 2 20\n"
        + "1 3 50\n"
        + "1 4 40\n"
        + "1 5 30\n"
        + "2 3 20\n"
        + "2 4 40\n"
        + "2 5 30\n"
        + "3 4 50\n"
   ,java-8"/>
	














    

		

        

            
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首页  > 解决方案 > 创建列表 inside map

I have string like: 



String input = "1 2 20\n"
        + "1 3 50\n"
        + "1 4 40\n"
        + "1 5 30\n"
        + "2 3 20\n"
        + "2 4 40\n"
        + "2 5 30\n"
        + "3 4 50\n"
   












java-8 - 创建列表 inside map

I have string like: 



String input = "1 2 20\n"
        + "1 3 50\n"
        + "1 4 40\n"
        + "1 5 30\n"
        + "2 3 20\n"
        + "2 4 40\n"
        + "2 5 30\n"
        + "3 4 50\n"
   





问题描述



I have string like: 



String input = "1 2 20\n"
        + "1 3 50\n"
        + "1 4 40\n"
        + "1 5 30\n"
        + "2 3 20\n"
        + "2 4 40\n"
        + "2 5 30\n"
        + "3 4 50\n"
        + "3 5 60\n"
        + "4 5 70\n";

  }




My Nodes Class:



class Nodes{
Integer from;
Integer to;
Integer cost;
}




Corresponding to each String input i want a Nodes object.



SO far I have been able to do like:    



 List<Nodes> collect = new ArrayList<>();




for loop starts here until the inputs are exhausted.



    String[] s = Arrays.stream("1 3 50".split(" ")).toArray(String[]::new);
    Nodes nodes = new Nodes(Integer.valueOf(s[0]),Integer.valueOf(s[1]),Integer.valueOf(s[2]));
collect.add(nodes);




for loop ends here
Required output : 



List<Nodes>




Is there a way so that I can create a List of Nodes inside stream only like map(h->new Nodes(h[0],h[1],h[2]))and at last collect it using Collectors.toList() so that i have List<Nodes>.









I don't code java but in python there's a function called list() that converts string to lists and maybe there is one on java too.
or maybe use split(", ") and maybe it will work. 


标签： java-8


解决方案









Try this one 



List<Nodes> nodes = Arrays.stream(input.split("\\n"))
            .map(s->s.split("\\s"))
            .map(arr->new Nodes(Integer.valueOf(arr[0]),Integer.valueOf(arr[1]),
                                Integer.valueOf(arr[2])))
            .collect(Collectors.toList());











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