String vmmType,
URI kernel) {
final Requirements_Type rtype = new Requirements_Type();
final ProcessorArchitectureEnumeration pae =
ProcessorArchitectureEnumeration.fromString(cpuType);
final CPUArchitecture_Type cpu = new CPUArchitecture_Type(pae, null);
rtype.setCPUArchitecture(cpu);
final String[] versions = {vmmVersion};
rtype.setVMM(new VMM_Type(VMM_TypeType.fromString(vmmType), versions));
if (kernel != null) {
final Kernel_Type kt = new Kernel_Type(kernel, null, null);