A Singleton with multiple instance which returns the good instance

MultiSingletonHelper.ts

class MultiSingletonHelper {
  private static readonly instances: MultiSingletonHelper[] = [];

  private readonly param1: string;

  private readonly param2?: string;

  private constructor(param1: string, param2?: string) {
    this.param1 = param1;
    this.param2 = param2;
  }

  public static getInstance(
    param1: string,
    param2?: string
  ): MultiSingletonHelper {
    const existingInstance = MultiSingletonHelper.instances.find(
      (instance) => instance.param1 === param1 && instance.param2 === param2
    );

    if (existingInstance) {
      return existingInstance;
    }

    const newInstance = new MultiSingletonHelper(param1, param2);
    MultiSingletonHelper.instances.push(newInstance);

    return newInstance;
  }
}