code: public void validate(RESTClient restClient) {
          Utils.require(this.commandName != null, "missing command name");
          
          //validate command name 
          this.metadataJson = matchCommand(restMetadataJson, this.commandName, commandParams.containsKey(STORAGE_SERVICE) ? (String)commandParams.get(STORAGE_SERVICE): _SYSTEM);
          if (this.metadataJson == null) {
          	//application command not found, look for system command
          	if (commandParams.containsKey(STORAGE_SERVICE)) {
          		this.metadataJson = matchCommand(restMetadataJson, this.commandName, _SYSTEM);
          	}
          }
        	if  (this.metadataJson == null) {      	
      		throw new RuntimeException("unsupported command name: " + this.commandName);
      	}        
          //validate required params
          validateRequiredParams();
      }
docs: Validate the command
  @param restClient