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# Apache Accumulo Batch Writing and Scanning Example

This is an example of how to use the BatchWriter and BatchScanner.

This tutorial uses the following Java classes.

 * [SequentialBatchWriter.java] - writes mutations with sequential rows and random values
 * [RandomBatchScanner.java] - reads random rows and verifies their values

Run `SequentialBatchWriter` to add 10000 entries with random 50 bytes values to Accumulo.

    $ ./bin/runex client.SequentialBatchWriter

Verify data was ingested by scanning the table using the Accumulo shell:

    $ accumulo shell
    root@instance> table examples.batch
    root@instance examples.batch> scan

Run `RandomBatchScanner` to perform 1000 random queries and verify the results.

    $ ./bin/runex client.RandomBatchScanner
    16:04:05,950 [examples.client.RandomBatchScanner] INFO : Generating 1000 random ranges for BatchScanner to read
    16:04:06,020 [examples.client.RandomBatchScanner] INFO : Reading ranges using BatchScanner
    16:04:06,283 [examples.client.RandomBatchScanner] TRACE: 100 lookups
    16:04:06,290 [examples.client.RandomBatchScanner] TRACE: 200 lookups
    16:04:06,294 [examples.client.RandomBatchScanner] TRACE: 300 lookups
    16:04:06,297 [examples.client.RandomBatchScanner] TRACE: 400 lookups
    16:04:06,301 [examples.client.RandomBatchScanner] TRACE: 500 lookups
    16:04:06,304 [examples.client.RandomBatchScanner] TRACE: 600 lookups
    16:04:06,307 [examples.client.RandomBatchScanner] TRACE: 700 lookups
    16:04:06,309 [examples.client.RandomBatchScanner] TRACE: 800 lookups
    16:04:06,316 [examples.client.RandomBatchScanner] TRACE: 900 lookups
    16:04:06,320 [examples.client.RandomBatchScanner] TRACE: 1000 lookups
    16:04:06,330 [examples.client.RandomBatchScanner] INFO : Scan finished! 3246.75 lookups/sec, 0.31 secs, 1000 results
    16:04:06,331 [examples.client.RandomBatchScanner] INFO : All expected rows were scanned

[SequentialBatchWriter.java]: ../src/main/java/org/apache/accumulo/examples/client/SequentialBatchWriter.java
[RandomBatchWriter.java]:  ../src/main/java/org/apache/accumulo/examples/client/RandomBatchWriter.java
[RandomBatchScanner.java]: ../src/main/java/org/apache/accumulo/examples/client/RandomBatchScanner.java