[HDDS-3560] HDDS-3560 OMFailoverProxyProvider throws IllegalAccessError when assigning proxy with Hadoop version < 3.2

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0
• Fix Version/s: 1.0.0
• Component/s: Ozone Client, Ozone Manager
• Labels: pull-request-available
• Assignee: Baolong Mao
• Reporter: Baolong Mao
• Created: 08/May/20 09:54
• Updated: 09/Jun/20 18:30
• Resolved: 12/May/20 23:32

Description

The method createOMProxyIfNeeded of OMFailoverProxyProvider will throw IllegalAccessError when work with hadoop version lower than 3.2.

The following is the problem code, it want assign a proxy to `proxyInfo.proxy`.

  private void createOMProxyIfNeeded(ProxyInfo proxyInfo,
      String nodeId) {
    if (proxyInfo.proxy == null) {
      InetSocketAddress address = omProxyInfos.get(nodeId).getAddress();
      try {
        proxyInfo.proxy = createOMProxy(address);
      } catch (IOException ioe) {
        LOG.error("{} Failed to create RPC proxy to OM at {}",
            this.getClass().getSimpleName(), address, ioe);
        throw new RuntimeException(ioe);
      }
    }
  }

But, hadoop lower than 3.2, the field proxy of proxyInfo is marked as final.

public static final class ProxyInfo<T> {
    public final T proxy;
    /*
     * The information (e.g., the IP address) of the current proxy object. It
     * provides information for debugging purposes.
     */
    public final String proxyInfo;
    ...
}

So, if we want to work around, we should catch the exception and new a ProxyInfo instance instead.

Issue Links

• links to: GitHub Pull Request #904