code: public ListVirtualRoutersResult withVirtualRouters(VirtualRouterRef... virtualRouters) {
          if (this.virtualRouters == null) {
              setVirtualRouters(new java.util.ArrayList<VirtualRouterRef>(virtualRouters.length));
          }
          for (VirtualRouterRef ele : virtualRouters) {
              this.virtualRouters.add(ele);
          }
          return this;
      }
docs: <p>
  The list of existing virtual routers for the specified service mesh.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setVirtualRouters(java.util.Collection)} or {@link #withVirtualRouters(java.util.Collection)} if you want
  to override the existing values.
  </p>
  
  @param virtualRouters
  The list of existing virtual routers for the specified service mesh.
  @return Returns a reference to this object so that method calls can be chained together.