import org.apache.hadoop.mapreduce.counters.LimitExceededException; //导入依赖的package包/类
private void testMaxCounters(final Counters counters) {
  LOG.info("counters max="+ Limits.getCountersMax());
  for (int i = 0; i < Limits.getCountersMax(); ++i) {
    counters.findCounter("test", "test"+ i);
  }
  setExpected(counters);
  shouldThrow(LimitExceededException.class, new Runnable() {
    public void run() {
      counters.findCounter("test", "bad");
    }
  });
  checkExpected(counters);
}
 

import org.apache.hadoop.mapreduce.counters.LimitExceededException; //导入依赖的package包/类
private void testMaxGroups(final Counters counters) {
  LOG.info("counter groups max="+ Limits.getGroupsMax());
  for (int i = 0; i < Limits.getGroupsMax(); ++i) {
    // assuming COUNTERS_MAX > GROUPS_MAX
    counters.findCounter("test"+ i, "test");
  }
  setExpected(counters);
  shouldThrow(LimitExceededException.class, new Runnable() {
    public void run() {
      counters.findCounter("bad", "test");
    }
  });
  checkExpected(counters);
}
 

import org.apache.hadoop.mapreduce.counters.LimitExceededException; //导入依赖的package包/类
@Test public void testResetOnDeserialize() throws IOException {
  // Allow only one counterGroup
  Configuration conf = new Configuration();
  conf.setInt(MRJobConfig.COUNTER_GROUPS_MAX_KEY, 1);
  Limits.init(conf);

  Counters countersWithOneGroup = new Counters();
  countersWithOneGroup.findCounter("firstOf1Allowed", "First group");
  boolean caughtExpectedException = false;
  try {
    countersWithOneGroup.findCounter("secondIsTooMany", "Second group");
  }
  catch (LimitExceededException _) {
    caughtExpectedException = true;
  }

  assertTrue("Did not throw expected exception",
      caughtExpectedException);

  Counters countersWithZeroGroups = new Counters();
  DataOutputBuffer out = new DataOutputBuffer();
  countersWithZeroGroups.write(out);

  DataInputBuffer in = new DataInputBuffer();
  in.reset(out.getData(), out.getLength());

  countersWithOneGroup.readFields(in);

  // After reset one should be able to add a group
  countersWithOneGroup.findCounter("firstGroupAfterReset", "After reset " +
      "limit should be set back to zero");
}
 

import org.apache.hadoop.mapreduce.counters.LimitExceededException; //导入依赖的package包/类
/**
 * Increments the counters with the counters from each task.
 * @param counters the counters to increment
 * @param tips the tasks to add in to counters
 * @return counters the same object passed in as counters
 */
private Counters incrementTaskCounters(Counters counters,
                                       TaskInProgress[] tips) {
  try {
    for (TaskInProgress tip : tips) {
      counters.incrAllCounters(tip.getCounters());
    }
  } catch (LimitExceededException e) {
    // too many user counters/groups, leaving existing counters intact.
  }
  return counters;
}
 

import org.apache.hadoop.mapreduce.counters.LimitExceededException; //导入依赖的package包/类
private void testMaxCounters(final Counters counters) {
  LOG.info("counters max="+ Limits.COUNTERS_MAX);
  for (int i = 0; i < Limits.COUNTERS_MAX; ++i) {
    counters.findCounter("test", "test"+ i);
  }
  setExpected(counters);
  shouldThrow(LimitExceededException.class, new Runnable() {
    public void run() {
      counters.findCounter("test", "bad");
    }
  });
  checkExpected(counters);
}
 

import org.apache.hadoop.mapreduce.counters.LimitExceededException; //导入依赖的package包/类
private void testMaxGroups(final Counters counters) {
  LOG.info("counter groups max="+ Limits.GROUPS_MAX);
  for (int i = 0; i < Limits.GROUPS_MAX; ++i) {
    // assuming COUNTERS_MAX > GROUPS_MAX
    counters.findCounter("test"+ i, "test");
  }
  setExpected(counters);
  shouldThrow(LimitExceededException.class, new Runnable() {
    public void run() {
      counters.findCounter("bad", "test");
    }
  });
  checkExpected(counters);
}