Regular Expression to remove every whitespace which is not after a comma-CodePudding

i want to replace remove/replace every whitespace in a string which is not after a comma. I already searched for a suitable regex but i did not find one. Here is a sample of the strings i want to modify:

{id=565189.0, server=Ealyn, merchantName=Nox, activeMerchants=[{id=f01b617d-2dc7-4597-2297-08dabad9a125, name=Nox, zone=Nebel horn, card={name=Bergstrom, rarity=2.0}, rapport={name=Energy X7 Capsule, rarity=3.0}, votes=0.0}]}

should change to (_ trough replace)

{id=565189.0, server=Ealyn, merchantName=Nox, activeMerchants=[{id=f01b617d-2dc7-4597-2297-08dabad9a125, name=Nox, zone=Nebel_horn, card={name=Bergstrom, rarity=2.0}, rapport={name=Energy_X7_Capsule, rarity=3.0}, votes=0.0}]}

Can someone with a high knowledge then me over regular expression's create one for this case? Thanks in advance

I already tried this expression:

(^|[^,])\\s

.. but it always removed a character with the whitespace

CodePudding user response：

This can be accomplished using a negative lookbehind:

(?<!,)\\s

The Output:

{id=565189.0, server=Ealyn, merchantName=Nox, activeMerchants=[{id=f01b617d-2dc7-4597-2297-08dabad9a125, name=Nox, zone=Nebel_horn, card={name=Bergstrom, rarity=2.0}, rapport={name=Energy_X7_Capsule, rarity=3.0}, votes=0.0}]}

CodePudding user response：

This worked for me. The trick is to choose the group you want to keep and reference it in the replacement parameter of the replaceAll method.

  public static void main(String[] args) {
    var before = "{id=565189.0, server=Ealyn, merchantName=Nox, activeMerchants=[{id=f01b617d-2dc7-4597-2297-08dabad9a125, name=Nox, zone=Nebel horn, card={name=Bergstrom, rarity=2.0}, rapport={name=Energy X7 Capsule, rarity=3.0}, votes=0.0}]}";
    var after = before.replaceAll("([^,])\\s ", "$1");
    System.out.println(before);
    System.out.println(after);
  }