code: public FleetData withLaunchTemplateConfigs(FleetLaunchTemplateConfig... launchTemplateConfigs) {
          if (this.launchTemplateConfigs == null) {
              setLaunchTemplateConfigs(new com.amazonaws.internal.SdkInternalList<FleetLaunchTemplateConfig>(launchTemplateConfigs.length));
          }
          for (FleetLaunchTemplateConfig ele : launchTemplateConfigs) {
              this.launchTemplateConfigs.add(ele);
          }
          return this;
      }
docs: <p>
  The launch template and overrides.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setLaunchTemplateConfigs(java.util.Collection)} or
  {@link #withLaunchTemplateConfigs(java.util.Collection)} if you want to override the existing values.
  </p>
  
  @param launchTemplateConfigs
  The launch template and overrides.
  @return Returns a reference to this object so that method calls can be chained together.