Apex Trigger Handler for Bucketing Contacts

ContractTriggerHandler.cls

//this class assumes you are running in a trigger context. it would be better to inherit from a base trigger class and replace 
//the reference on line 11 with that.
public without sharing class ContactTriggerHandler {
  
  private map<string, id> saMap = new Map<string, id>();
  
  public static final Integer keyLength = 2;
  // Constructor
  public ContactTriggerHandler() {
    //better: replace static reference to trigger with something from a base handler
    if (Trigger.isInsert) {
      setup((List<Contact>) newObjs);
    }
  }

  public void beforeInsert(SObject so) {
    Contact c = (Contact) so;

    if (shouldBucket(c)) {
      //bucket key is first 2 of last name, Z-padded to 2 chars
      string nameKey = getNameKey(c);
      if (saMap.containsKey(nameKey)) {
        //found key
        c.AccountId = saMap.get(nameKey);
      } else {
        //TODO log and throw exception - setup should have made this impossible
      }
    } 
  }


  public void setup(List<Contact> newContacts) {
	//replace with your own method for getting the record type to use for these accounts
    Id rType_systemAccount = AccountRepository.RECORD_TYPE_SYSTEM;

	//update the where clause to select the user who will own the acounts
    User genericApi = [SELECT Id FROM User WHERE ExternalID__c = 'XXXXAPI' LIMIT 1];

    list<Account> accAdd = new List<Account>();
  
    cacheSystemAccounts(false);

    Set<string> nameKeys = new Set<string>();

    boolean newSystemAccounts = false;
    
    for (Contact c : newContacts) {
        nameKeys.add(getNameKey(c));
    }

    for (string namekey : nameKeys) {
      if (!saMap.containsKey(nameKey)) {
        //we have at least one contact that needs this key.
        Account a = new Account(
          Name = nameKey + ' System Account Bucket',
          RecordTypeId = rType_systemAccount,
          SystemExternalId__c = nameKey,
          Type = 'Other',
          OwnerId = genericApi.Id
        );
        saMap.put(nameKey, a.Id);
        accAdd.add(a);
        newSystemAccounts = true;
      }
    }

    if (newSystemAccounts) {
      insert accAdd;
      cacheSystemAccounts(newSystemAccounts);
    }
  }

  @testVisible
  private string getNameKey(Contact c) {
    string nameCopy = c.LastName.replaceAll('[^\\w]', '');
    return nameCopy.left(keyLength).rightPad(keyLength, 'Z').toUpperCase();
  }

  private void cacheSystemAccounts(boolean forceUpdate) {
    if (saMap.size() > 0 && !forceUpdate)
      return;

    List<Account> sysAccts = [
      SELECT id, SystemExternalID__c
      FROM Account
      WHERE RecordTypeId = :rType_systemAccount AND Type = 'Other'
    ];
    for (Account a : sysAccts) {
      saMap.put(a.SystemExternalID__c, a.id);
    }
  }
}