A null pointer exception is thrown when trying to list bucket objects on the buckets directory.

[douglasAtJoyent]

A null pointer exception is thrown when trying to list bucket objects on the buckets directory.

e.g.
client.listObjects(client.getContext().getMantaBucketsDirectory());

The exception that I see is :
java.lang.NullPointerException: Modification time is null
at com.joyent.manta.org.apache.commons.lang3.Validate.notNull(Validate.java:225)
at com.joyent.manta.client.MantaObjectConversionFunction.apply(MantaObjectConversionFunction.java:83)
at com.joyent.manta.client.MantaObjectConversionFunction.apply(MantaObjectConversionFunction.java:29)
at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
at java.util.Iterator.forEachRemaining(Iterator.java:116)
at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
at com.joyent.jmetersampler.AtomicBucketListing.runTest(AtomicBucketListing.java:93)
at org.apache.jmeter.protocol.java.sampler.JavaSampler.sample(JavaSampler.java:197)
at org.apache.jmeter.threads.JMeterThread.doSampling(JMeterThread.java:622)
at org.apache.jmeter.threads.JMeterThread.executeSamplePackage(JMeterThread.java:546)
at org.apache.jmeter.threads.JMeterThread.processSampler(JMeterThread.java:486)
at org.apache.jmeter.threads.JMeterThread.run(JMeterThread.java:253)
at java.lang.Thread.run(Thread.java:745)

[kennethvt437]

Before the line that is throwing the exception, I would recommend writing the following:
System.out.println(client == null);
System.out.println(client.getContext() == null);

If either of the booleans printed is true, look back in your code to see whether you correctly initialized the exception-causing variable.