docs: public void setDirectConnectGatewayAssociationProposals(
              java.util.Collection<DirectConnectGatewayAssociationProposal> directConnectGatewayAssociationProposals) {
          if (directConnectGatewayAssociationProposals == null) {
              this.directConnectGatewayAssociationProposals = null;
              return;
          }
  
          this.directConnectGatewayAssociationProposals = new com.amazonaws.internal.SdkInternalList<DirectConnectGatewayAssociationProposal>(
                  directConnectGatewayAssociationProposals);
      }