/*
* Copyright 2010 The Apache Software Foundation
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.bizosys.hsearch.hbase;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.RowLock;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.filter.Filter;
import com.bizosys.oneline.SystemFault;
import com.bizosys.hsearch.common.RecordScalar;
import com.bizosys.hsearch.common.Storable;
public class HReader {
/**
* Scalar data will contain the amount to increase
* @param tableName
* @param scalar
* @throws SystemFault
*/
public static long generateKeys(String tableName,
RecordScalar scalar, long amount ) throws SystemFault {
HBaseFacade facade = null;
HTableWrapper table = null;
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
long incrementedValue = table.incrementColumnValue(
scalar.pk.toBytes(), scalar.kv.family.toBytes(),
scalar.kv.name.toBytes(), amount);
return incrementedValue;
} catch (Exception ex) {
throw new SystemFault("Error in getScalar :" + scalar.toString(), ex);
} finally {
if ( null != facade && null != table) facade.putTable(table);
}
}
public static boolean exists (String tableName, byte[] pk) throws SystemFault{
HBaseFacade facade = null;
HTableWrapper table = null;
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
Get getter = new Get(pk);
return table.exists(getter);
} catch (Exception ex) {
throw new SystemFault("Error in existance checking :" + pk.toString(), ex);
} finally {
if ( null != facade && null != table) facade.putTable(table);
}
}
public static List<NVBytes> getCompleteRow (String tableName,
byte[] pk) throws SystemFault{
return getCompleteRow (tableName, pk, null, null);
}
public static List<NVBytes> getCompleteRow (String tableName, byte[] pk,
Filter filter) throws SystemFault {
return getCompleteRow (tableName, pk, filter, null);
}
public static List<NVBytes> getCompleteRow (String tableName, byte[] pk,
Filter filter, RowLock lock) throws SystemFault {
HBaseFacade facade = null;
HTableWrapper table = null;
Result r = null;
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
Get getter = ( null == lock) ? new Get(pk) : new Get(pk,lock);
if (null != filter) getter.setFilter(filter);
if ( table.exists(getter) ) {
r = table.get(getter);
List<NVBytes> nvs = new ArrayList<NVBytes>(r.list().size());
for (KeyValue kv : r.list()) {
NVBytes nv = new NVBytes(kv.getFamily(),kv.getQualifier(), kv.getValue());
nvs.add(nv);
}
return nvs;
}
return null;
} catch (Exception ex) {
throw new SystemFault("Error in existance checking :" + pk.toString(), ex);
} finally {
if ( null != facade && null != table) facade.putTable(table);
}
}
public static void getScalar (String tableName, RecordScalar scalar) throws SystemFault {
HBaseFacade facade = null;
HTableWrapper table = null;
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
Get getter = new Get(scalar.pk.toBytes());
Result result = table.get(getter);
byte[] val = result.getValue(scalar.kv.family.toBytes(), scalar.kv.name.toBytes());
if ( null != val ) scalar.kv.data = new Storable(val);
} catch (Exception ex) {
throw new SystemFault("Error in getScalar :" + scalar.toString(), ex);
} finally {
if ( null != facade && null != table) facade.putTable(table);
}
}
public static byte[] getScalar (String tableName,
byte[] family, byte[] col, byte[] pk) throws SystemFault{
if ( null == family || null == col || null == pk ) return null;
HBaseFacade facade = null;
HTableWrapper table = null;
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
Get getter = new Get(pk);
Result result = table.get(getter);
return result.getValue(family, col);
} catch (Exception ex) {
StringBuilder sb = new StringBuilder();
sb.append("Input during exception = Table : [").append(tableName);
sb.append("] , Family : [").append(Storable.getString(family));
sb.append("] , Column : [").append(Storable.getString(col));
sb.append("] , Key : [").append(Storable.getString(pk));
sb.append(']');
throw new SystemFault(sb.toString(), ex);
} finally {
if ( null != facade && null != table) facade.putTable(table);
}
}
public static void getAllValues(String tableName, NV kv,
IScanCallBack callback ) throws SystemFault {
HBaseFacade facade = null;
ResultScanner scanner = null;
HTableWrapper table = null;
List<byte[]> matched = null;
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
Scan scan = new Scan();
scan.setCacheBlocks(true);
scan.setCaching(500);
scan.setMaxVersions(1);
scan = scan.addColumn(kv.family.toBytes(), kv.name.toBytes());
scanner = table.getScanner(scan);
long timeS = System.currentTimeMillis();
for (Result r: scanner) {
if ( null == r) continue;
if ( r.isEmpty()) continue;
byte[] storedBytes = r.getValue(kv.family.toBytes(), kv.name.toBytes());
if ( null == storedBytes) continue;
callback.process(storedBytes);
}
if ( HbaseLog.l.isDebugEnabled()) {
long timeE = System.currentTimeMillis();
HbaseLog.l.debug("HReader.getAllValues (" + tableName + ") = " +
(timeE - timeS) );
}
} catch ( IOException ex) {
throw new SystemFault(ex);
} finally {
if ( null != scanner) scanner.close();
if ( null != table ) facade.putTable(table);
if ( null != matched) matched.clear();
}
}
/**
* Get the keys of the table
* @param tableName Table name
* @param kv Key-Value
* @param startKey Start Row Primary Key
* @param pageSize Page size
* @return Record Keys
* @throws SystemFault
*/
public static List<byte[]> getAllKeys(String tableName, NV kv,
byte[] startKey, int pageSize) throws SystemFault {
HBaseFacade facade = null;
ResultScanner scanner = null;
HTableWrapper table = null;
List<byte[]> keys = new ArrayList<byte[]>(pageSize);
try {
facade = HBaseFacade.getInstance();
table = facade.getTable(tableName);
Scan scan = new Scan();
scan.setCacheBlocks(true);
scan.setCaching(500);
scan.setMaxVersions(1);
scan = scan.addColumn(kv.family.toBytes(), kv.name.toBytes());
if ( null != startKey) scan = scan.setStartRow(startKey);
scanner = table.getScanner(scan);
int counter = 0;
for (Result r: scanner) {
if ( null == r) continue;
if ( r.isEmpty()) continue;
if ( counter++ > pageSize) break;
keys.add(r.getRow());
}
return keys;
} catch ( IOException ex) {
throw new SystemFault(ex);
} finally {
if ( null != scanner) scanner.close();
if ( null != table ) facade.putTable(table);
}
}
}