一、准备阶段
开发环境:
hadoop: hadoop -2.4.0
hbase: hbase -0.94.11-security
eclipse:Juno Service Release 2
二、创建 hbasedemo项目
1、通过 Eclipse 创建一个新 Java 工程
2、右击项目根目录,选择“Propertiesà> Java Build Pathà> Libraryà> Add External JARs”
3、添加jar文件到 classpath
3.1 解压 HBase 安装文件
3.2 拷贝 hbase-0.94.7-security.jar、 hbase-0.94.11-security-tests.jar到工程
3.3 lib 子目录下所有的 jar 包添加到本工程的 Build Path下
三、使用HBase JAVA API
初始化和释放资源方法:
public void init() 数据初始化
public void destory() 释放资源
验证方法:
public void testCreate() 验证创建表
public void testDrop() 验证删除表
public void testPut()验证添加表数据
public void testGetByRowKey() 验证如何通过rowkey获取数据
public void testScanSToEnd() 验证范围行数据获取
public void testScanAll() 验证全表扫描
方法:
public List<Cell> get(String tableName, String rowKey) 通过rowKey插入表数据
public List<Result> scan(String tableName) 通过表名查询所有信息
public List<Result> scan(String tableName,String startRow,String stopRow) 查询范围行方法
public void create(String tableName, String[] cfs) 通过表名和列族信息创建表
public void drop(String tableName) 删除表
public void put(String tableName, List<CellBean> values) 根据提供的表和对象信息插入hbase
第一步: 封装HBase中的存储单元Cell对象
/**
* 封装HBase中存储单元cell对象
* @author shenfl
* @version:V1.0
* @Date:2015-6-8
*/
public class CellBean {
//行健
private String rowKey;
//列族
private String columnFamilly;
//列名
private String columnName;
//cell值
private String columnValue;
public String getRowKey() {
return rowKey;
}
public void setRowKey(String rowKey) {
this.rowKey = rowKey;
}
public String getColumnFamilly() {
return columnFamilly;
}
public void setColumnFamilly(String columnFamilly) {
this.columnFamilly = columnFamilly;
}
public String getColumnName() {
return columnName;
}
public void setColumnName(String columnName) {
this.columnName = columnName;
}
public String getColumnValue() {
return columnValue;
}
public void setColumnValue(String columnValue) {
this.columnValue = columnValue;
}
}
第二步: 使用HBase JAVA API 操作HBase 数据库
/**
* 使用HBase JAVA API操作
*
* @author shenfl
*
*/
public class HBaseTest {
Configuration config = null;
// 创建操作表對象
HBaseAdmin admin = null;
// hbase的连接
HConnection conn = null;
@Before
public void init() {
config = HBaseConfiguration.create();
// HBase只需要知道ZooKeeper,就可以操作RegionServer上的數據,设置HBase 连接ZooKeeper
config.set("hbase.zookeeper.quorum", "192.168.2.35:2181,192.168.2.36:2181,192.168.2.37:2181");
try {
conn = HConnectionManager.createConnection(config);
admin = new HBaseAdmin(config);
} catch (Exception e) {
e.printStackTrace();
}
}
@After
public void destory() {
try {
admin.close();
conn.close();
} catch (IOException e) {
e.printStackTrace();
}
}
@Test
public void testCreate() {
String tableName = "account";
String[] columnFamilies = new String[] { "info", "other" };
create(tableName, columnFamilies);
}
//@Test
public void testDrop() {
drop("account");
}
@Test
public void testPut() {
// 设置表对象列表
List<CellBean> cbList = new ArrayList<CellBean>();
// 设置表名account
String tableName = "account";
CellBean e = null;
for(int i=0;i<3;i++){
e = new CellBean();
e.setRowKey("g20142500"+i);
e.setColumnFamilly("info");
e.setColumnName("username");
e.setColumnValue("shenfl"+i);
cbList.add(e);
e = new CellBean();
e.setRowKey("g20142500"+i);
e.setColumnFamilly("other");
e.setColumnName("career");
e.setColumnValue("singer"+i);
cbList.add(e);
}
put(tableName, cbList);
}
@Test
public void testGetByRowKey() {
String tableName = "account";
String rowKey = "g201425001";
List<Cell> cells = get(tableName, rowKey);
StringBuffer info = new StringBuffer();
for (Cell c : cells) {
//使用CellUtil方法输出对应列, hbase0.96 版本使用CellUtil函数
info.append(new String(CellUtil.cloneFamily(c))).append(":")
.append(new String(CellUtil.cloneQualifier(c))).append("\t")
.append(new String(CellUtil.cloneValue(c))).append("\n");
}
System.out.println(info);
}
@Test
public void testScanSToEnd(){
StringBuffer sb = new StringBuffer();
String tableName = "account";
String startRow = "g201425000";
String stopRow = "g201425002";
List<Result> rsList = scan(tableName, startRow, stopRow);
byte[] rowKey = null;
byte[] username = null;
byte[] career = null;
for(Result rs:rsList){
rowKey = rs.getRow();
username = rs.getValue(Bytes.toBytes("info"), Bytes.toBytes("username"));
career = rs.getValue(Bytes.toBytes("other"), Bytes.toBytes("career"));
sb.append(new String(rowKey)).append("\t")
.append(new String(username)).append("\t")
.append(new String(career)).append("\n");
}
System.out.println(sb.toString());
}
@Test
public void testScanAll() {
StringBuffer sb = new StringBuffer();
List<Result> rsList = scan("account");
for (Result rs : rsList) {
List<Cell> listCells = rs.listCells();
for (Cell c : listCells) {
// 使用CellUtil方法输出对应列, hbase0.96 版本使用CellUtil函数
sb.append(new String(CellUtil.cloneRow(c))).append("\t")
.append(new String(CellUtil.cloneFamily(c))).append(":")
.append(new String(CellUtil.cloneQualifier(c))).append("\t")
.append(new String(CellUtil.cloneValue(c))).append("\n");
}
}
System.out.println(sb);
}
/**
* 通过rowKey插入表数据
* @param tableName 表名
* @param rowKey 行健
* @return
*/
public List<Cell> get(String tableName, String rowKey) {
HTableInterface table = null;
Get get = null;
Result rs = null;
List<Cell> listCells = new ArrayList<Cell>();
try {
table = conn.getTable(tableName);
get = new Get(Bytes.toBytes(rowKey));
rs = table.get(get);
listCells = rs.listCells();
} catch (IOException e) {
e.printStackTrace();
}finally{
try {
table.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return listCells;
}
/**
* 查询所有行
*
* @param tableName
* @return
*/
public List<Result> scan(String tableName) {
HTableInterface table = null;
List<Result> rsList = new ArrayList<Result>();
try {
table = conn.getTable(tableName);
Scan scan = new Scan();
ResultScanner scanner = table.getScanner(scan);
Iterator<Result> iterator = scanner.iterator();
Result rs = null;
while (iterator.hasNext()) {
rs = (Result) iterator.next();
rsList.add(rs);
}
} catch (Exception e) {
e.printStackTrace();
}finally{
try {
table.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return rsList;
}
/**
* 查询范围行
* @param tableName 表名
* @param startRow 开始的行健
* @param stopRow 结束行健
* @return
*/
public List<Result> scan(String tableName,String startRow,String stopRow) {
HTableInterface table = null;
List<Result> rsList = new ArrayList<Result>();
try {
table = conn.getTable(tableName);
Scan scan = new Scan();
scan.setStartRow(Bytes.toBytes(startRow));
scan.setStopRow(Bytes.toBytes(stopRow));
ResultScanner rs = table.getScanner(scan);
for(Result v:rs){
rsList.add(v);
}
} catch (Exception e) {
e.printStackTrace();
}finally{
try {
table.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return rsList;
}
/**
* 创建壁报
*
* @param tableName
* 表名
* @param cfs
* 列族
*/
public void create(String tableName, String[] cfs) {
if (cfs == null || cfs.length == 0) {
return;
}
try {
// 校验表是否存储
if (admin.tableExists(tableName)) {
return;
}
// 创建表
HTableDescriptor desc = new HTableDescriptor(TableName.valueOf(tableName));
// 创建列族
for (String cf : cfs) {
desc.addFamily(new HColumnDescriptor(cf));
}
// 创建表
admin.createTable(desc);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 删除表
*
* @param tableName
* 表名
*/
public void drop(String tableName) {
try {
if(admin.tableExists(tableName)){
admin.disableTable(tableName);
admin.deleteTable(tableName);
}
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 向指定表插入数据
*
* @param tableName
* 表名
* @param values
* 数据
*/
public void put(String tableName, List<CellBean> values) {
if (StringUtils.isBlank(tableName) || values == null || values.size() == 0) {
return;
}
Put put = null;
HTableInterface table = null;
try {
table = conn.getTable(tableName);
for (CellBean v : values) {
put = new Put(Bytes.toBytes(v.getRowKey()));
put.add(Bytes.toBytes(v.getColumnFamilly()), Bytes.toBytes(v.getColumnName()),
Bytes.toBytes(v.getColumnValue()));
table.put(put);
}
} catch (Exception e) {
// 实际生产环境要通过记录日志,例如: logger.warn("xxxxx",e);
e.printStackTrace();
}finally{
try {
table.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
参考文章:
1、HBase连接池 -- HTablePool被Deprecated之后
2、HBase Java API 介绍
3、HBase Java API 操作案例
http://www.programcreek.com/java-api-examples/index.php?api=org.apache.hadoop.hbase.HTableDescriptor
http://hbase.apache.org/apidocs/org/apache/hadoop/hbase/client/Admin.html
标签:JAVA,String,void,tableName,API,new,1006,public,append From: https://blog.51cto.com/u_14361901/6167564