I have been developing my first RESTful server utilizing such technologies as Spring and HBase.
Message
below is the core model of my server;
@AllArgsConstructor
@Getter
public class Message {
private final String from;
private final String to;
private final long when;
}
My server should save and find messages into HBase.
I have already made research and read this documentation: https://docs.spring.io/spring-hadoop/docs/2.5.0.RELEASE/reference/html/springandhadoop-hbase.html#data-access-object-dao-support
However, it's not enough. The tutorial doesn't expose how to find by a specific column.
Could you provide a code snippet that retrieves a message from HBase based on the following query?
SELECT from, to, when FROM Message WHERE to = {userId} OR from = {userId}
There is an example to make a column based query as given below:
Scan scan = new Scan();
scan.addColumn(HbaseJsonEventSerializer.COLUMFAMILY_FILTERS_BYTES,
Bytes.toBytes(columnName));
Filter filter = new SingleColumnValueFilter(HbaseJsonEventSerializer.COLUMFAMILY_FILTERS_BYTES,
Bytes.toBytes(columnName), CompareOp.EQUAL, Bytes.toBytes(columnValue));
scan.setFilter(filter);
List<String> rows =
hbaseTemplate.find("searchclicks", scan, new RowMapper<String>() {
@Override
public String mapRow(Result result, int rowNum) throws Exception {
byte[] value = result.getValue(
HbaseJsonEventSerializer.COLUMFAMILY_FILTERS_BYTES,
Bytes.toBytes(columnName));
if (value != null) {
String facetValue = new String(value);
LOG.debug("Facet field: {} and Facet Value: {}",
new Object[] { columnName, facetValue });
}
return facetValue;
}
});
You can refer this for more examples:
https://www.programcreek.com/java-api-examples/?code=jaibeermalik/searchanalytics-bigdata/searchanalytics-bigdata-master/src/main/java/org/jai/hbase/HbaseServiceImpl.java