public static void main(String[] args) throws Exception {
conf.set("hbase.zookeeper.quorum", "hadoop271.itversity.com");
conf.set("hbase.zookeeper.property.clientPort", "2181");
Connection connection = ConnectionFactory.createConnection(conf);
Table table = connection.getTable(TableName.valueOf("demo"));
Scan scan1 = new Scan();
ResultScanner scanner1 = table.getScanner(scan1);
for (Result res : scanner1) {
System.out.println(Bytes.toString(res.getRow()));
System.out.println(Bytes.toString(res.getValue("cf1".getBytes(), "column1".getBytes())));
System.out.println(Bytes.toString(res.getValue("cf1".getBytes(), "column2".getBytes())));
}
scanner1.close();
Put put = new Put("3".getBytes());
put.addColumn("cf1".getBytes(), "column1".getBytes(), "value1".getBytes());
put.addColumn("cf1".getBytes(), "column2".getBytes(), "value2".getBytes());
table.put(put);
Get get = new Get("3".getBytes());
Result getResult = table.get(get);
System.out.println("Printing colunns for rowkey 3");
System.out.println(Bytes.toString(getResult.getValue("cf1".getBytes(), "column1".getBytes())));
System.out.println(Bytes.toString(getResult.getValue("cf1".getBytes(), "column2".getBytes())));
scanner1 = table.getScanner(scan1);
System.out.println("Before Delete");
for (Result res : scanner1) {
System.out.println(Bytes.toString(res.getRow()));
System.out.println(Bytes.toString(res.getValue("cf1".getBytes(), "column1".getBytes())));
System.out.println(Bytes.toString(res.getValue("cf1".getBytes(), "column2".getBytes())));
}
scanner1.close();
Delete del = new Delete("3".getBytes());
table.delete(del);
System.out.println("After Delete");
scanner1 = table.getScanner(scan1);
for (Result res : scanner1) {
System.out.println(Bytes.toString(res.getRow()));
System.out.println(Bytes.toString(res.getValue("cf1".getBytes(), "column1".getBytes())));
System.out.println(Bytes.toString(res.getValue("cf1".getBytes(), "column2".getBytes())));
}
scanner1.close();
table.close();
connection.close();
}
protected void deleteRegion(Configuration conf, final Table tbl, byte[] startKey, byte[] endKey)
throws IOException {
LOG.info("Before delete:");
HTableDescriptor htd = tbl.getTableDescriptor();
dumpMeta(htd);
List<HRegionLocation> regions;
try (RegionLocator rl = connection.getRegionLocator(tbl.getName())) {
regions = rl.getAllRegionLocations();
}
for (HRegionLocation e : regions) {
HRegionInfo hri = e.getRegionInfo();
ServerName hsa = e.getServerName();
if (Bytes.compareTo(hri.getStartKey(), startKey) == 0
&& Bytes.compareTo(hri.getEndKey(), endKey) == 0) {
LOG.info("RegionName: " + hri.getRegionNameAsString());
byte[] deleteRow = hri.getRegionName();
TEST_UTIL.getHBaseAdmin().unassign(deleteRow, true);
LOG.info("deleting hdfs data: " + hri.toString() + hsa.toString());
Path rootDir = FSUtils.getRootDir(conf);
FileSystem fs = rootDir.getFileSystem(conf);
Path p = new Path(FSUtils.getTableDir(rootDir, htd.getTableName()), hri.getEncodedName());
fs.delete(p, true);
try (Table meta = this.connection.getTable(TableName.META_TABLE_NAME)) {
Delete delete = new Delete(deleteRow);
meta.delete(delete);
}
}
LOG.info(hri.toString() + hsa.toString());
}
TEST_UTIL.getMetaTableRows(htd.getTableName());
LOG.info("After delete:");
dumpMeta(htd);
}
protected void wipeOutMeta() throws IOException {
// Mess it up by blowing up meta.
Admin admin = TEST_UTIL.getHBaseAdmin();
Scan s = new Scan();
Table meta = TEST_UTIL.getConnection().getTable(TableName.META_TABLE_NAME);
ResultScanner scanner = meta.getScanner(s);
List<Delete> dels = new ArrayList<Delete>();
for (Result r : scanner) {
HRegionInfo info = HRegionInfo.getHRegionInfo(r);
if (info != null
&& !info.getTable()
.getNamespaceAsString()
.equals(NamespaceDescriptor.SYSTEM_NAMESPACE_NAME_STR)) {
Delete d = new Delete(r.getRow());
dels.add(d);
admin.unassign(r.getRow(), true);
}
}
meta.delete(dels);
scanner.close();
meta.close();
}
/**
* Delete a record from the database.
*
* @param table The name of the table
* @param key The record key of the record to delete.
* @return Zero on success, a non-zero error code on error
*/
@Override
public Status delete(String table, String key) {
// if this is a "new" table, init HTable object. Else, use existing one
if (!tableName.equals(table)) {
currentTable = null;
try {
getHTable(table);
tableName = table;
} catch (IOException e) {
System.err.println("Error accessing HBase table: " + e);
return Status.ERROR;
}
}
if (debug) {
System.out.println("Doing delete for key: " + key);
}
final Delete d = new Delete(Bytes.toBytes(key));
d.setDurability(durability);
try {
if (clientSideBuffering) {
Preconditions.checkNotNull(bufferedMutator);
bufferedMutator.mutate(d);
} else {
currentTable.delete(d);
}
} catch (IOException e) {
if (debug) {
System.err.println("Error doing delete: " + e);
}
return Status.ERROR;
}
return Status.OK;
}
public static void main(String[] args) throws IOException {
Configuration conf = HBaseConfiguration.create();
conf.set(
"hbase.zookeeper.quorum",
"master-1.internal.larsgeorge.com,"
+ "master-2.internal.larsgeorge.com,master-3.internal.larsgeorge.com");
HBaseHelper helper = HBaseHelper.getHelper(conf);
helper.dropTable("testtable");
helper.createTable("testtable", "colfam1");
System.out.println("Adding rows to table...");
helper.fillTable("testtable", 1, 5, 1, "colfam1");
System.out.println("Table before the operations:");
helper.dump("testtable");
Connection connection = ConnectionFactory.createConnection(conf);
TableName tableName = TableName.valueOf("testtable");
Table table = connection.getTable(tableName);
// vv ScanConsistencyExample1
Scan scan = new Scan();
scan.setCaching(
1); // co ScanConsistencyExample1-1-ConfScan Configure scan to iterate over each row
// separately.
ResultScanner scanner = table.getScanner(scan);
// ^^ ScanConsistencyExample1
System.out.println("Starting scan, reading one row...");
// vv ScanConsistencyExample1
Result result = scanner.next();
helper.dumpResult(result);
// ^^ ScanConsistencyExample1
System.out.println("Applying mutations...");
// vv ScanConsistencyExample1
Put put = new Put(Bytes.toBytes("row-3"));
put.addColumn(Bytes.toBytes("colfam1"), Bytes.toBytes("col-1"), Bytes.toBytes("val-999"));
table.put(put); // co ScanConsistencyExample1-2-Put Update a later row with a new value.
Delete delete = new Delete(Bytes.toBytes("row-4"));
table.delete(
delete); // co ScanConsistencyExample1-3-Delete Remove an entire row, that is located at the
// end of the scan.
// ^^ ScanConsistencyExample1
System.out.println("Resuming original scan...");
// vv ScanConsistencyExample1
for (Result result2 : scanner) {
helper.dumpResult(
result2); // co ScanConsistencyExample1-4-Scan Scan the rest of the table to see if the
// mutations are visible.
}
scanner.close();
// ^^ ScanConsistencyExample1
System.out.println("Print table under new scanner...");
// vv ScanConsistencyExample1
helper.dump(
"testtable"); // co ScanConsistencyExample1-5-Dump Print the entire table again, with a new
// scanner instance.
// ^^ ScanConsistencyExample1
table.close();
connection.close();
helper.close();
}