How do I convert a multiple strings into a set of strings?-CodePudding

So I have following strings,

String a = "123, 541, 123"
String b = "527"
String c = "234, 876"

I would like to loop over these strings, split the string by "," and store it in a set of string so that I have such final output,

("123", "541", "527", "234", "876")

Any idea how I can achieve this?

I have tried splitting the string but that results in Set<String[]> and not sure how to proceed with this since I am very new to this.

CodePudding user response：

First, you need to separate strings in "a" and "c" variable. For that you can you can you split() method. You can try code below and adapt it in a way that fits your needs.

Set<String> strings = new HashSet<>();

String a = "123, 541, 123";
String b = "527";
String c = "234, 876";

private void addToSet(String stringNumbers) {
    
    for(String str : Arrays.asList(stringNumbers.split(","))) {
        strings.add(str);
    }
    
}

CodePudding user response：

I would do it simply like that:

    String a = "123, 541, 123";
    String b = "527";
    String c = "234, 876";
    
    List<String> all = Arrays.asList((a   ","   b   ","   c).split(","));
    Set<String> result = new HashSet<>();
    for (String s : all) {
        result.add(s.trim());
    }

    System.out.println(result); // [123, 541, 234, 876, 527]

But I would try to the change the situtation that you have 3 different strings in the first place. Input should be an Array of Strings, so you don't have to care, if it is 1 or 37238273 different strings.

But without knowing where you have these 3 strings from, why they are 3 variables, hard to advice how to actually optimize that.

CodePudding user response：

Something like this:

List<String> all = Arrays.asList((a   ", "   b   ", "   c).split(", "));

CodePudding user response：

A simple approach with Stream flat-mapping:

Set<String> result = Stream.of(a, b, c)
        .map(s -> s.split(", "))
        .flatMap(Arrays::stream)
        .collect(Collectors.toSet());

CodePudding user response：

try it plz.

Set<String> result = new HashSet<>();
for (String s : (a   ","   b   ","   c).split(",")) {
    result.add(s.trim());
}

CodePudding user response：

In Java 9:

import java.util.Set;
Set<String> result = Set.of("123", "541", "527", "234", "876");