hbase-client是HBase提供的一套比较底层的API,在实际使用时需要对其进行封装,提供更好用的api给用户。
操作hbase的客户端有以下几种方式:
package org.apache.hadoop.hbase.client;
public class ConnectionFactory {
/*
* 创建连接
* @param conf hbase属性配置
*/
public static Connection createConnection(Configuration conf) throws IOException;
}
package org.apache.hadoop.hbase
public class HBaseConfiguration extends Configuration {
public static Configuration create();
/**
* 设置hbase的属性配置
* @param name property name.
* @param value property value.
*/
public void set(String name, String value);
}
public interface Connection extends Abortable, Closeable {
Admin getAdmin() throws IOException;
Table getTable(TableName tableName) throws IOException;
void close() throws IOException;
}
public final class TableName implements Comparable<TableName> {
public static TableName valueOf(String name);
}
public final class TableName {
public static TableName valueOf(String name);
default Result get(Get get) throws IOException;
default void close() throws IOException
}
public interface Table extends Closeable {
default void delete(Delete delete) throws IOException;
default void put(Put put) throws IOException;
default ResultScanner getScanner(Scan scan) throws IOException;
default Result get(Get get) throws IOException;
}
public interface ResultScanner extends Closeable, Iterable<Result> {
void close();
}
public class TableDescriptorBuilder {
public static TableDescriptorBuilder newBuilder(final TableName name);
public TableDescriptor build();
public TableDescriptorBuilder setColumnFamilies(Collection<ColumnFamilyDescriptor> families);
}
public class ColumnFamilyDescriptorBuilder {
public static ColumnFamilyDescriptorBuilder newBuilder(final byte[] name);
public ColumnFamilyDescriptor build();
}
public interface ColumnFamilyDescriptor {
}
public class Get extends Query implements Row {
public Get(byte [] row);
public Get addColumn(byte [] family, byte [] qualifier);
}
public class Put extends Mutation implements HeapSize {
public Put(byte [] row);
public Put addColumn(byte [] family, byte [] qualifier, byte [] value);
}
public class Delete extends Mutation {
public Delete addFamily(final byte [] family);
public Delete addColumn(final byte [] family, final byte [] qualifier);
}
public class Scan extends Query {
public Scan setFilter(Filter filter);
}
public class RowFilter extends CompareFilter {
public RowFilter(final CompareOperator op, final ByteArrayComparable rowComparator);
}
public class Result implements CellScannable, CellScanner {
public List<Cell> listCells();
byte[] getValueArray();
int getValueOffset();
int getValueLength();
}
public interface Admin extends Abortable, Closeable {
boolean tableExists(TableName tableName) throws IOException;
void createTable(TableDescriptor desc) throws IOException;
void disableTable(TableName tableName) throws IOException;
void deleteTable(TableName tableName) throws IOException;
}
public class Result implements CellScannable, CellScanner {
public Cell[] rawCells();
public NavigableMap<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> getMap();
}
public interface Cell {
byte[] getRowArray();
byte[] getFamilyArray();
byte[] getQualifierArray();
byte[] getValueArray();
int getValueOffset();
int getValueLength();
}
public class Bytes implements Comparable<Bytes> {
// This method will convert utf8 encoded bytes into a string
public static String toString(final byte[] b, int off, int len);
}
hbase-client 使用步骤可分为五步:
<dependency>
<groupId>org.apache.hbasegroupId>
<artifactId>hbase-clientartifactId>
<version>2.1.3version>
dependency>
hbase:
config:
hbase.zookeeper.quorum: 127.0.0.1
hbase.zookeeper.port: 2181
hbase.zookeeper.znode: /hbase
hbase.client.keyvalue.maxsize: 1572864000
import org.springframework.boot.context.properties.ConfigurationProperties;
import java.util.Map;
@ConfigurationProperties(prefix = "hbase")
public class HbaseProperties {
private Map<String, String> config;
public Map<String, String> getConfig() {
return config;
}
public void setConfig(Map<String, String> config) {
this.config = config;
}
}
@Configuration
@EnableConfigurationProperties(HbaseProperties.class)
public class HbaseConfig {
private final HbaseProperties properties;
public HbaseConfig(HbaseProperties properties) {
this.properties = properties;
}
public org.apache.hadoop.conf.Configuration configuration() {
org.apache.hadoop.conf.Configuration configuration = HBaseConfiguration.create();
Map<String, String> config = properties.getConfig();
Set<String> keySet = config.keySet();
for (String key : keySet) {
configuration.set(key, config.get(key));
}
return configuration;
}
}
这里只是简单的demo实现,如要实际使用还需要对其完善封装。
@DependsOn("hbaseConfig")
@Component
public class HBaseClient {
@Autowired
private HbaseConfig config;
private static Connection connection = null;
private static Admin admin = null;
private Logger logger = LoggerFactory.getLogger(this.getClass());
@PostConstruct
private void init() {
if (connection != null) {
return;
}
try {
connection = ConnectionFactory.createConnection(config.configuration());
admin = connection.getAdmin();
} catch (IOException e) {
logger.error("HBase create connection failed: {}", e);
}
}
public void createTable(String tableName, String[] columnFamilies) throws IOException {
TableName name = TableName.valueOf(tableName);
boolean isExists = this.tableExists(tableName);
if (isExists) {
throw new TableExistsException(tableName + "is exists!");
}
TableDescriptorBuilder descriptorBuilder = TableDescriptorBuilder.newBuilder(name);
List<ColumnFamilyDescriptor> columnFamilyList = new ArrayList<>();
for (String columnFamily : columnFamilies) {
ColumnFamilyDescriptor columnFamilyDescriptor = ColumnFamilyDescriptorBuilder.newBuilder(columnFamily.getBytes()).build();
columnFamilyList.add(columnFamilyDescriptor);
}
descriptorBuilder.setColumnFamilies(columnFamilyList);
TableDescriptor tableDescriptor = descriptorBuilder.build();
admin.createTable(tableDescriptor);
}
public void insertOrUpdate(String tableName, String rowKey, String columnFamily, String column, String value) throws IOException {
this.insertOrUpdate(tableName, rowKey, columnFamily, new String[]{column}, new String[]{value});
}
public void insertOrUpdate(String tableName, String rowKey, String columnFamily, String[] columns, String[] values) throws IOException {
Table table = connection.getTable(TableName.valueOf(tableName));
Put put = new Put(Bytes.toBytes(rowKey));
for (int i = 0; i < columns.length; i++) {
put.addColumn(Bytes.toBytes(columnFamily), Bytes.toBytes(columns[i]), Bytes.toBytes(values[i]));
table.put(put);
}
}
public void deleteRow(String tableName, String rowKey) throws IOException {
Table table = connection.getTable(TableName.valueOf(tableName));
Delete delete = new Delete(rowKey.getBytes());
table.delete(delete);
}
public void deleteColumnFamily(String tableName, String rowKey, String columnFamily) throws IOException {
Table table = connection.getTable(TableName.valueOf(tableName));
Delete delete = new Delete(rowKey.getBytes());
delete.addFamily(Bytes.toBytes(columnFamily));
table.delete(delete);
}
public void deleteColumn(String tableName, String rowKey, String columnFamily, String column) throws IOException {
Table table = connection.getTable(TableName.valueOf(tableName));
Delete delete = new Delete(rowKey.getBytes());
delete.addColumn(Bytes.toBytes(columnFamily), Bytes.toBytes(column));
table.delete(delete);
}
public void deleteTable(String tableName) throws IOException {
boolean isExists = this.tableExists(tableName);
if (!isExists) {
return;
}
TableName name = TableName.valueOf(tableName);
admin.disableTable(name);
admin.deleteTable(name);
}
public String getValue(String tableName, String rowkey, String family, String column) {
Table table = null;
String value = "";
if (StringUtils.isBlank(tableName) || StringUtils.isBlank(family)
|| StringUtils.isBlank(rowkey) || StringUtils.isBlank(column)) {
return null;
}
try {
table = connection.getTable(TableName.valueOf(tableName));
Get g = new Get(rowkey.getBytes());
g.addColumn(family.getBytes(), column.getBytes());
Result result = table.get(g);
List<Cell> ceList = result.listCells();
if (ceList != null && ceList.size() > 0) {
for (Cell cell : ceList) {
value = Bytes.toString(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
}
}
} catch (IOException e) {
e.printStackTrace();
}finally {
try {
table.close();
connection.close();
}catch (IOException e) {
e.printStackTrace();
}
}
return value;
}
public String selectOneRow(String tableName, String rowKey) throws IOException {
Table table = connection.getTable(TableName.valueOf(tableName));
Get get = new Get(rowKey.getBytes());
Result result = table.get(get);
NavigableMap<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> map = result.getMap();
for (Cell cell : result.rawCells()) {
String row = Bytes.toString(cell.getRowArray());
String columnFamily = Bytes.toString(cell.getFamilyArray());
String column = Bytes.toString(cell.getQualifierArray());
String value = Bytes.toString(cell.getValueArray());
// 可以通过反射封装成对象(列名和Java属性保持一致)
System.out.println(row);
System.out.println(columnFamily);
System.out.println(column);
System.out.println(value);
}
return null;
}
public String scanTable(String tableName, String rowKeyFilter) throws IOException {
Table table = connection.getTable(TableName.valueOf(tableName));
Scan scan = new Scan();
if (!StringUtils.isEmpty(rowKeyFilter)) {
RowFilter rowFilter = new RowFilter(CompareOperator.EQUAL, new SubstringComparator(rowKeyFilter));
scan.setFilter(rowFilter);
}
ResultScanner scanner = table.getScanner(scan);
try {
for (Result result : scanner) {
System.out.println(Bytes.toString(result.getRow()));
for (Cell cell : result.rawCells()) {
System.out.println(cell);
}
}
} finally {
if (scanner != null) {
scanner.close();
}
}
return null;
}
/**
* 判断表是否已经存在,这里使用间接的方式来实现
*
* admin.tableExists() 会报NoSuchColumnFamilyException, 有人说是hbase-client版本问题
* @param tableName
* @return
* @throws IOException
*/
public boolean tableExists(String tableName) throws IOException {
TableName[] tableNames = admin.listTableNames();
if (tableNames != null && tableNames.length > 0) {
for (int i = 0; i < tableNames.length; i++) {
if (tableName.equals(tableNames[i].getNameAsString())) {
return true;
}
}
}
return false;
}
}
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;
import java.io.IOException;
@RunWith(SpringRunner.class)
@SpringBootTest
public class HbaseDemoApplicationTests {
@Autowired
private HBaseClient hBaseClient;
/**
* 测试删除、创建表
*/
@Test
public void testGetValue() {
String value = hBaseClient.getValue("tbl_user", "mengday", "info", "age");
System.out.println(value);
}
@Test
public void testCreateTable() throws IOException {
String tableName = "tbl_abc";
hBaseClient.deleteTable(tableName);
hBaseClient.createTable(tableName, new String[] {"cf1", "cf2"});
}
@Test
public void dropTable() throws IOException {
hBaseClient.deleteTable("tbl_abc");
}
@Test
public void testInsertOrUpdate() throws IOException {
hBaseClient.insertOrUpdate("tbl_abc", "rowKey1", "cf1", new String[]{"c1", "c2"}, new String[]{"v1", "v22"});
}
@Test
public void testSelectOneRow() throws IOException {
hBaseClient.selectOneRow("tbl_abc", "rowKey1");
}
@Test
public void testScanTable() throws IOException {
hBaseClient.scanTable("tbl_abc", "rowKey1");
}
}