Changing string with comma separated values to numbered new-line values
For example:
Input: a,b,c
Output:
1.a
2.b
3.c
Finding it hard to change it using regex pattern, instead of converting string to string array and looping through.
I'm not really sure, that it's possible to achive with only regex without any kind of a loop. As fore me, the solution with spliting the string into an array and iterating over it, is the most straightforward:
String value = "a,b,c";
String[] values = value.split(",");
String result = "";
for (int i=1; i<=values.length; i++) {
result += i + "." + values[i-1] + "\n";
}
Sure, it's possible to do without splitting and any kind of arrays, but it could be a little bit awkward solution, like:
String value = "a,b,c";
Pattern pattern = Pattern.compile("[(^\\w+)]");
Matcher matcher = pattern.matcher(value.replaceAll("\\,", "\n"));
StringBuffer s = new StringBuffer();
int i = 0;
while (matcher.find()) {
matcher.appendReplacement(s, ++i + "." + matcher.group());
}
System.out.println(s.toString());
Here the , sign is replaced with \n new line symbol and then we are looking for a groups of characters at the start of every line [(^\\w+)]. If any group is found, then we are appending to the start of this group a line number. But even here we have to use a loop to set the line number. And this logic is not as clear, as the first one.
System.out.println(Arrays.toString("a,b,c".split("\\,")));you can try this.