Using HBase-dsl
At the beginning of last month I started prototyping various solutions for a customer using HBase. However I found myself writing tons of code to perform some fairly simple tasks. So I set out to simply my HBase code and ended up writing a Java HBase DSL. It's still fairly rough around the edges but it does allow the use of standard Java types and it's extensible.
Simple Put and Get Example
Direct HBase API:
Scanner Example
Direct HBase API:
See the unit tests, for more examples.
Simple Put and Get Example
Direct HBase API:
public class PutAndGet {
public static void main(String[] args) throws IOException {
HTable hTable = new HTable("test");
byte[] rowId = Bytes.toBytes("abcd");
byte[] famA = Bytes.toBytes("famA");
byte[] col1 = Bytes.toBytes("col1");
Put put = new Put(rowId).
add(famA, col1, Bytes.toBytes("hello world!"));
hTable.put(put);
Get get = new Get(rowId);
Result result = hTable.get(get);
byte[] value = result.getValue(famA, col1);
System.out.println(Bytes.toString(value));
}
}
HBase-dsl API:public class PutAndGetWithDsl {
public static void main(String[] args) throws IOException {
HBase<QueryOps, String> hBase = new HBase<QueryOps<String>, String>(String.class);
hBase.save("test").
row("abcd").
family("famA").
col("col1", "hello world!");
String value = hBase.fetch("test").
row("abcd").
family("famA").
value("col1", String.class)
System.out.println(value);
}
}
Now this is where the dsl becomes more powerful!Scanner Example
Direct HBase API:
public class Scanner {
public static void main(String[] args) throws IOException {
byte[] famA = Bytes.toBytes("famA");
byte[] col1 = Bytes.toBytes("col1");
HTable hTable = new HTable("test");
Scan scan = new Scan(Bytes.toBytes("a"), Bytes.toBytes("z"));
scan.addColumn(famA, col1);
SingleColumnValueFilter singleColumnValueFilterA = new SingleColumnValueFilter(
famA, col1, CompareOp.EQUAL, Bytes.toBytes("hello world!"));
singleColumnValueFilterA.setFilterIfMissing(true);
SingleColumnValueFilter singleColumnValueFilterB = new SingleColumnValueFilter(
famA, col1, CompareOp.EQUAL, Bytes.toBytes("hello hbase!"));
singleColumnValueFilterB.setFilterIfMissing(true);
FilterList filter = new FilterList(Operator.MUST_PASS_ONE, Arrays
.asList((Filter) singleColumnValueFilterA,
singleColumnValueFilterB));
scan.setFilter(filter);
ResultScanner scanner = hTable.getScanner(scan);
for (Result result : scanner) {
System.out.println(Bytes.toString(result.getValue(famA, col1)));
}
}
}
HBase-dsl API:public class ScannerWithDsl {
public static void main(String[] args) throws IOException {
HBase<QueryOps, String> hBase = new HBase<QueryOps<String>, String>(String.class);
hBase.scan("test","a","z").
select().
family("famA").
col("col1").
where().
family("famA").
col("col1").eq("hello world!","hello hbase!").
foreach(new ForEach() {
@Override
public void process(Row row) {
System.out.println(row.value("famA", "col1", String.class));
}
});
}
}
See the unit tests, for more examples.
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This is great. Thanks for the code. I am going to start testing immediately. Have you updated the code since your last post here?