public class GetCountryFromIP extends EvalFunc<String> {
@Override
public List<String> getCacheFiles() {
    List<String> list = new ArrayList<String>(1);
    list.add("/input/pig/resources/GeoLite2-Country.mmdb#GeoLite2-Country");
    return list;
}
@Override
public String exec(Tuple input) throws IOException {
    if (input == null || input.size() == 0 || input.get(0) == null) {
        return null;
    }

    try {
        String inputIP = (String) input.get(0);
        String output;
        File database = new File("./GeoLite2-Country");

 //CODE FOR EXPLAIN

        if (database.exists()) {
            System.out.print("EXIST!!!");
        } else {
            System.out.print("NOTEXISTS!!!");
        }

 //CODE FOR EXPLAIN

        DatabaseReader reader = new DatabaseReader.Builder(database).build();
        InetAddress ipAddress = InetAddress.getByName(inputIP);
        CountryResponse response = reader.country(ipAddress);
        Country country = response.getCountry();
        output = country.getIsoCode();
        return output;
    } catch (AddressNotFoundException e) {
        return null;
    } catch (Exception ee) {
        throw new IOException("Uncaught exec" + ee);
    }
}

}

这是我的udf代码，我需要geolite2-count.mmdb文件，所以使用getcachefile。
我还把所有的pig拉丁语放在一个pig文件中，“batch.pig”
当我运行这个文件'pig batch.pig'
像这样输出接缝

2015-10-06 01:16:56,737 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.MapTask - soft limit at 83886080
2015-10-06 01:16:56,737 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.MapTask - bufstart = 0; bufvoid = 104857600
2015-10-06 01:16:56,737 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.MapTask - kvstart = 26214396; length = 6553600
2015-10-06 01:16:56,738 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.MapTask - Map output collector class = org.apache.hadoop.mapred.MapTask$MapOutputBuffer
2015-10-06 01:16:56,744 [LocalJobRunner Map Task Executor #0] WARN  org.apache.pig.data.SchemaTupleBackend - SchemaTupleBackend has already been initialized
2015-10-06 01:16:56,754 [LocalJobRunner Map Task Executor #0] INFO  org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapReduce$Map - Aliases being processed per job phase (AliasName[line,offset]): M: weblog[-1,-1],weblog_web[30,13],weblog_web[-1,-1],weblog_web[-1,-1],desktop_active_log_account_filter[7,36],desktop_parsed[3,18],desktop_parsed_abstract[5,26],weblog_web[-1,-1],web_active_log_account_filter[20,32],weblog_web_parsed[16,20],weblog_web_parsed_abstract[18,29] C:  R: 
EXIST!!!
2015-10-06 01:16:56,997 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.LocalJobRunner - 
2015-10-06 01:16:56,997 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.MapTask - Starting flush of map output

...
...
...

2015-10-06 01:16:57,938 [Thread-1885] INFO  org.apache.hadoop.mapred.LocalJobRunner - reduce task executor complete.
2015-10-06 01:16:57,939 [pool-59-thread-1] WARN  org.apache.pig.data.SchemaTupleBackend - SchemaTupleBackend has already been initialized
NOTEXIST!!!
2015-10-06 01:16:57,974 [pool-59-thread-1] INFO  org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigMapReduce$Reduce - Aliases being processed per job phase (AliasName[line,offset]): M: account_hour_activity[42,24],account_hour_activity_group[41,30],team_hour_activity[76,21],team_hour_activity_group[75,27] C: 
...
...
..

2015-10-06 01:16:57,976 [LocalJobRunner Map Task Executor #0] INFO  org.apache.hadoop.mapred.MapTask - Finished spill 0
2015-10-06 01:16:57,977 [Thread-2139] INFO  org.apache.hadoop.mapred.LocalJobRunner - map task executor complete.
2015-10-06 01:16:57,981 [Thread-2139] WARN  org.apache.hadoop.mapred.LocalJobRunner - job_local1209692101_0021
java.lang.Exception: org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: Local Rearrange[tuple]{tuple}(true) - scope-2240 Operator Key: scope-2240): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: weblog_web_parsed_abstract: New For Each(false,false,false)[bag] - scope-1379 Operator Key: scope-1379): org.apache.pig.backend.executionengine.ExecException: ERROR 2078: Caught error from UDF: com.tosslab.sprinklr.country.GetCountryFromIP [Uncaught execjava.io.FileNotFoundException: ./GeoLite2-Country (No such file or directory)]
    at org.apache.hadoop.mapred.LocalJobRunner$Job.runTasks(LocalJobRunner.java:462)
    at org.apache.hadoop.mapred.LocalJobRunner$Job.run(LocalJobRunner.java:522)
Caused by: org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: Local Rearrange[tuple]{tuple}(true) - scope-2240 Operator Key: scope-2240): org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: weblog_web_parsed_abstract: New For Each(false,false,false)[bag] - scope-1379 Operator Key: scope-1379): org.apache.pig.backend.executionengine.ExecException: ERROR 2078: Caught error from UDF: com.tosslab.sprinklr.country.GetCountryFromIP [Uncaught execjava.io.FileNotFoundException: ./GeoLite2-Country (No such file or directory)]
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.processInput(PhysicalOperator.java:316)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POLocalRearrange.getNextTuple(POLocalRearrange.java:291)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POSplit.runPipeline(POSplit.java:259)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POSplit.processPlan(POSplit.java:241)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POSplit.processPlan(POSplit.java:246)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POSplit.getNextTuple(POSplit.java:233)
    at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapBase.runPipeline(PigGenericMapBase.java:283)
    at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapBase.map(PigGenericMapBase.java:278)
    at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigGenericMapBase.map(PigGenericMapBase.java:64)
    at org.apache.hadoop.mapreduce.Mapper.run(Mapper.java:145)
    at org.apache.hadoop.mapred.MapTask.runNewMapper(MapTask.java:784)
    at org.apache.hadoop.mapred.MapTask.run(MapTask.java:341)
    at org.apache.hadoop.mapred.LocalJobRunner$Job$MapTaskRunnable.run(LocalJobRunner.java:243)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.pig.backend.executionengine.ExecException: ERROR 0: Exception while executing (Name: weblog_web_parsed_abstract: New For Each(false,false,false)[bag] - scope-1379 Operator Key: scope-1379): org.apache.pig.backend.executionengine.ExecException: ERROR 2078: Caught error from UDF: com.tosslab.sprinklr.country.GetCountryFromIP [Uncaught execjava.io.FileNotFoundException: ./GeoLite2-Country (No such file or directory)]
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.processInput(PhysicalOperator.java:316)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.relationalOperators.POForEach.getNextTuple(POForEach.java:246)
    at org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator.processInput(PhysicalOperator.java:307)
    ... 17 more

这意味着mmdb文件在批处理过程中被删除。。。
这是怎么回事？我怎样才能解决这个问题？