AccumuloParameters Examples

This page will familiarize you with the scan settings possible using AccumuloParameters

This class delegate the following parameters to an internal instance of CommonParameters which implements Parameters

1. MAX_RESULTS = control the number of key/value pairs to scan over.
2. TABLE_NAME = table to search.
3. BATCH_SIZE = number of key/value pairs to return for each round trip.
4. CF_AND_QUAL_LIST = list of column_family:qualifier pairs to search. Can operate with just column_family.
5. START_KEY = lower bound of scanning range.
6. END_KEY = upper bound of scanning range.

In addition to these parameters, AccumuloParameters offers a number of Accumulo-specific parameters.

1. ZOOKEEPERS = comma-delimited list of zookeepers.
2. INSTANCE_NAME = Accumulo instance for connection.
3. USER = Current user to authenticate and scan.
4. PASSWORD = password for current user.

AccumuloParameters uses the Builder pattern to enforce parameter immutability after creation.

The below code creates a Builder instance for the root user that scans the 'people' table between keys '0' and '3'. Only the 'info' column family is requested.

AccumuloParameters.Builder builder = new AccumuloParameters.Builder()
                .setUser("root")
                .setPassword("password")
                .setStartKey("0")
                .setEndKey("3")
                .setTable("people")
                .setColumns(new String[]{"info"});

If we decide to insert our own custom named object, we can do so.

builder.addNamedProperty("CUSTOM_PARAM", param);

Additionally, we can supply iterators to apply during scan time

builder.addIteratorSetting(myIteratorSetting);

Finally we're ready to build an instance of AccumuloParameters

AccumuloParameters params = builder.build();