import org.apache.hadoop.yarn.security.client.RMDelegationTokenSelector; //导入依赖的package包/类
@VisibleForTesting
void addHistoryToken(Credentials ts) throws IOException, InterruptedException {
	/* check if we have a hsproxy, if not, no need */
	MRClientProtocol hsProxy = clientCache.getInitializedHSProxy();
	if (UserGroupInformation.isSecurityEnabled() && (hsProxy != null)) {
		/*
		 * note that get delegation token was called. Again this is hack for
		 * oozie to make sure we add history server delegation tokens to the
		 * credentials
		 */
		RMDelegationTokenSelector tokenSelector = new RMDelegationTokenSelector();
		Text service = resMgrDelegate.getRMDelegationTokenService();
		if (tokenSelector.selectToken(service, ts.getAllTokens()) != null) {
			Text hsService = SecurityUtil.buildTokenService(hsProxy.getConnectAddress());
			if (ts.getToken(hsService) == null) {
				ts.addToken(hsService, getDelegationTokenFromHS(hsProxy));
			}
		}
	}
}
 

import org.apache.hadoop.yarn.security.client.RMDelegationTokenSelector; //导入依赖的package包/类
@VisibleForTesting
void addHistoryToken(Credentials ts) throws IOException, InterruptedException {
  /* check if we have a hsproxy, if not, no need */
  MRClientProtocol hsProxy = clientCache.getInitializedHSProxy();
  if (UserGroupInformation.isSecurityEnabled() && (hsProxy != null)) {
    /*
     * note that get delegation token was called. Again this is hack for oozie
     * to make sure we add history server delegation tokens to the credentials
     */
    RMDelegationTokenSelector tokenSelector = new RMDelegationTokenSelector();
    Text service = resMgrDelegate.getRMDelegationTokenService();
    if (tokenSelector.selectToken(service, ts.getAllTokens()) != null) {
      Text hsService = SecurityUtil.buildTokenService(hsProxy
          .getConnectAddress());
      if (ts.getToken(hsService) == null) {
        ts.addToken(hsService, getDelegationTokenFromHS(hsProxy));
      }
    }
  }
}
 

import org.apache.hadoop.yarn.security.client.RMDelegationTokenSelector; //导入依赖的package包/类
@VisibleForTesting
void addHistoryToken(Credentials ts) throws IOException, InterruptedException {
  /* check if we have a hsproxy, if not, no need */
  MRClientProtocol hsProxy = clientCache.getInitializedHSProxy();
  if (UserGroupInformation.isSecurityEnabled() && (hsProxy != null)) {
    /*
     * note that get delegation token was called. Again this is hack for oozie
     * to make sure we add history server delegation tokens to the credentials
     */
    RMDelegationTokenSelector tokenSelector = new RMDelegationTokenSelector();
    Text service = SecurityUtil.buildTokenService(resMgrDelegate
        .getConnectAddress());
    if (tokenSelector.selectToken(service, ts.getAllTokens()) != null) {
      Text hsService = SecurityUtil.buildTokenService(hsProxy
          .getConnectAddress());
      if (ts.getToken(hsService) == null) {
        ts.addToken(hsService, getDelegationTokenFromHS(hsProxy));
      }
    }
  }
}