SystemMetrics parse error

In some OS environment, Chukwa Agent cannot fetch all the system data, but in the Chukwa Collector, the parse format is hard coded, so this will lead to a NullPointException, and this NullPointException will lead to other Exception.

For example:
In my cluster, swap information can not be retrieved, so this exception will thrown:
java.lang.NullPointerException
at org.apache.hadoop.chukwa.extraction.demux.processor.mapper.SystemMetrics.parse(SystemMetrics.java:156)
at org.apache.hadoop.chukwa.extraction.demux.processor.mapper.AbstractProcessor.process(AbstractProcessor.java:82)
at org.apache.hadoop.chukwa.datacollection.writer.hbase.HBaseWriter.add(HBaseWriter.java:194)
at org.apache.hadoop.chukwa.datacollection.writer.SocketTeeWriter.add(SocketTeeWriter.java:252)
at org.apache.hadoop.chukwa.datacollection.writer.PipelineStageWriter.add(PipelineStageWriter.java:40)
at org.apache.hadoop.chukwa.datacollection.collector.servlet.ServletCollector.accept(ServletCollector.java:159)
at org.apache.hadoop.chukwa.datacollection.collector.servlet.ServletCollector.doPost(ServletCollector.java:208)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:401)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:451)

AbstractProcessor class catch this error and saved in a error chunk, this error chunk is also packaged in KeyValue format and put in HBase, but there is no related HBase column family named "SystemMetricsInError", so another exception is thrown:
HBaseWriter - org.apache.hadoop.hbase.client.RetriesExhaustedWithDetailsException: Failed 1 action: DoNotRetryIOException: 1 time, servers with issues: sr116:60020,
at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.processBatchCallback(HConnectionManager.java:1591)
at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.processBatch(HConnectionManager.java:1367)
at org.apache.hadoop.hbase.client.HTable.flushCommits(HTable.java:945)
at org.apache.hadoop.hbase.client.HTable.doPut(HTable.java:801)
at org.apache.hadoop.hbase.client.HTable.put(HTable.java:784)
at org.apache.hadoop.hbase.client.HTablePool$PooledHTable.put(HTablePool.java:402)
at org.apache.hadoop.chukwa.datacollection.writer.hbase.HBaseWriter.add(HBaseWriter.java:195)
at org.apache.hadoop.chukwa.datacollection.writer.SocketTeeWriter.add(SocketTeeWriter.java:252)
at org.apache.hadoop.chukwa.datacollection.writer.PipelineStageWriter.add(PipelineStageWriter.java:40)
at org.apache.hadoop.chukwa.datacollection.collector.servlet.ServletCollector.accept(ServletCollector.java:159)
at org.apache.hadoop.chukwa.datacollection.collector.servlet.ServletCollector.doPost(ServletCollector.java:208)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:401)
at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:766)
at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
at org.mortbay.jetty.Server.handle(Server.java:326)
at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:945)
at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:451)

There exists two problems:
1. until I meet parse error, I have already collect some metrics data. But after I throw an exception, the left part of data will not be parsed, so half-integrity data will be put into HBase. If this half-integrity data do not include "tags:cluster" column, so the cluster name will not be fetch by HICC, this really is the problem.
2. if error parsed data need to be saved, another column family "SytemMetricsInError" should be created.