大数据技术----HBase Jave编程

Java to Hbase

配置Hbase环境
编辑类文件
Java操作表
Java操作表数据
比较运算符、比较器
过滤器的AND/OR

配置Hbase环境

然后在工程的src右键–new java package
在包内new class file

编辑类文件

导入相关的类：

使用Hadoop配置

import org.apache.hadoop.conf.Configuration;

Hbase的客户端

import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.client.Connection;//连接类
import org.apache.hadoop.hbase.client.ConnectionFactory;//使用这个建立连接对象
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Table;

import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;

import java.io.IOException;

声明三个全局变量

public class hbaseJavaProgramme {
	
	//声明三个全局变量
	public static Configuration conf;
	public static Connection  conn;
	public static Admin admin;
	

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		//创建配置对象
		conf = HbaseConfiguration.create();
		conf.set("hbase.zookeeper.quorum","localhost");
		conf.set("hbase.zookeeper.property.clientPort","2181");
		try{
			conn = ConnectionFactory.createConnection(conf);
			admin = conn.getAdmin();//操作表
			if(admin.tableExists(TableName.valueOf("lauf"))){
				admin.disableTable(TableName.valueOf("lauf"));
				admin.isTableDisabled(TableName.valueOf("lauf"))；
				admin.deleteTable(TableName.valueOf("lauf"));
			}
			//创建表
			HTableDescriptor tdesc = new HTableDescriptor(TableName.valueOf("lauf"));
			tdesc.addFamily(new HColumnDescriptor("StuInfo"));
			admin.createTable(tdesc);
		}catch(IOException e){
			e.print.StackTrace();
		}
	}

}

Java操作表

创建一个表

//先判断是否存在该表，存在则删除
HTableDescriptor tdesc = new HTableDescriptor(TableName.valueOf("lauf"));
tdesc.addFamily(new HColumnDescriptor("StuInfo"));
admin.createTable(tdesc);

删除一个表

if(admin.tableExists(TableName.valueOf("lauf"))){
	admin.disableTable(TableName.valueOf("lauf"));
	admin.deleteTable(TableName.valueOf("lauf"));
}

表的描述符类：

import org.apache.hadoop.hbase.HTableDescriptor
HTableDescriptor tdesc = new HTableDescriptor(TableNme.valueOf("lauf"));

//描述表结构admin.getTableDescriptor(TableName tableName)
//说明表的类型
//是否只读tdesc.isReadonly()
//设置列族缓存大小tdesc.setMemStoreFlushSize(64*1024*1024);默认单位bytes
//设置最大StoreFile，tdesc.setMaxFileSize(256*1024*1024);
//增加列族tdesc.addFamily(HColumnDescriptor obj)
//删除列族tdesc.removeFamily("StuInfo".getBytes())

通过表描述符获取信息：
tdesc.getNameAsString();获取表名，返回字符串
tdesc.getFamilies();获取所有列族，HColumnDescriptor对象集合，如下,

Collection collection = tdesc.getFamilies();//返回列族集合
Iterator iterator = collection.iterator();//集合转为迭代器
while(iterator.hasNext()){
	HColumnDescriptor colDesc = (HColumnDescriptor)iterator.next();
	String colName = colDesc.getNameAsString();
	System.out.println(colName);
}

tdesc.getColumnFamilies();返回所有列族的数组

HColumnDescriptor[] a = tdesc.getColumnFamilies();
for(HColumnDescriptor columnDescriptor : a) {
	String s = columnDescriptor.getNameAsString();
	System.out.println(s);
}

通过列簇描述符获取、设置单元格的值：

String s = columnDescriptor.getNameAsString();
				
byte[] key = "Name".getBytes();
byte[] s1 = columnDescriptor.getValue(key);
System.out.println(s1);

Java操作表数据

Put/Delete/Get/Scan
全部在org.apache.hadoop.hbase.client.xxx
studentTable.put(Put obj);插入一行的一个或者多个cell
studentTable.delete(Delete obj);删除一行/列族/列
studentTable.get(Get obj);获取一行/列族/列
studentTable.getScanner(scan);

import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;

TableName studentTableName = TableName.valueOf("Student");
Table studentTable = conn.getTable(studentTableName);

//插入数据
//insert data
public static void insertData() throws IOException{
		//获取表名对象
	TableName stuTableName = TableName.valueOf("Student");
	//获取该表对象
	Table studenTable = conn.getTable(stuTableName);
	//创建Put对象，并增加key-value
	Put put = new Put("003".getBytes());
	put.addColumn("StuInfo".getBytes(), "Name".getBytes(), "lauf".getBytes());
	put.addColumn("StuInfo".getBytes(), "Age".getBytes(), "23".getBytes());
	
	studenTable.put(put);//也可以是一个put集合
	
	ArrayList list = new ArrayList();
	for(int i=0;i<5;i++) {
		Put put1 = new Put(("00"+(i+4)).getBytes());
		put1.addColumn("StuInfo".getBytes(), "Name".getBytes(), String.valueOf(i).getBytes());
		list.add(put1);
	}
	studenTable.put(list);
	studenTable.close();//释放所有资源
	}

//delete data
//delete data,只是标记为删除
public static void deleteData() throws IOException{
	Table stuTable = conn.getTable(TableName.valueOf("Student"));
	Delete delete = new Delete("003".getBytes());//删除行
	delete.addColumn("StuInfo".getBytes(), "Age".getBytes());//删除列
	//delete.addFamily(xxx)//删除列族
	
	stuTable.delete(delete);
	stuTable.close();
	}

//get查询数据
import org.apache.hadoop.hbase.client.Result;//单行
import org.apache.hadoop.hbase.client.ResultScanner;//多行
import org.apache.hadoop.hbase.Cell;//一个单元格
import org.apache.hadoop.hbase.CellUtil;//操作cell

//get data
public static void getRow(String tableName, String rowKey) throws IOException {  
	Table table = conn.getTable(TableName.valueOf(tableName));
	Get get = new Get(Bytes.toBytes(rowKey));  
	Result result = table.get(get);  
	for (Cell cell : result.rawCells()) {  
		System.out.println(  
		"行键:" + new String(CellUtil.cloneRow(cell)) + "t" +  
		"列族:" + new String(CellUtil.cloneFamily(cell)) + "t" +   
		"列名:" + new String(CellUtil.cloneQualifier(cell)) + "t" +   
		"值:" + new String(CellUtil.clonevalue(cell)) + "t" +  
		"时间戳:" + cell.getTimestamp());  
	}  
	
	table.close();  
}

//扫描数据
//scan data
public static void scanTable(String tableName) throws IOException {  
       Table table = conn.getTable(TableName.valueOf(tableName)); 
       Scan scan = new Scan();  
       ResultScanner results = table.getScanner(scan);  
       for(Result result : results){  
           for (Cell cell : result.rawCells()) {  
               System.out.println(  
                       "行键:" + new String(CellUtil.cloneRow(cell)) + "t" +  
                       "列族:" + new String(CellUtil.cloneFamily(cell)) + "t" +   
                       "列名:" + new String(CellUtil.cloneQualifier(cell)) + "t" +   
                       "值:" + new String(CellUtil.clonevalue(cell)) + "t" +  
                       "时间戳:" + cell.getTimestamp());  
           } 
       } 
       table.close();
   }

//带有过滤器的san 
import org.apache.hadoop.hbase.filter.*

Scan scan = new Scan();       
Filter f1 = new RowFilter(CompareOp.GREATER, new BinaryComparator("002".getBytes()));
scan.setFilter(f1);//设置一个过滤器
ResultScanner results = table.getScanner(scan);  
for(Result result : results){  
    for (Cell cell : result.rawCells()) {  
}

//多个过滤器
Filter f1 = new RowFilter(CompareOp.GREATER,new BinaryComparator("005".getBytes()));
Filter f2 = new ColumnPrefixFilter("Name".getBytes());
FilterList filterList = new FilterList(f1,f2,..);
scan.setFilter(filterList);//过滤器集合

比较运算符、比较器

过滤器的AND/OR

设置一个Filter

Scan scan = new Scan();
Filter f1 = new RowFilter(CompareOp.GREATER，new BinaryComparator("001".getBytes()));
scan.setFilter(f1);

//多条结果
ResultScanner results = table.getScanner(scan);

设置多个过滤器时，需要指定是AND操作，还是OR操作

Filter f1 = new RowFilter(CompareOp.LESS,new SubstringComparator("003".getBytes()));
Filter f2 = new SingleColumnValueFilter("StuInfo".getBytes,"Age".getBytes(),CompareOp.LESS,new BinaryComparator("24".getBytes()));
//过滤器集合
FilterList filterList = new FilterList(Operator.MUST_PASS_ALL);//AND操作
FilterList filterList1 = new FilterList(Operator.MUST_PASS_ONE);//OR操作

filterList.addFilter(f1);
filterList.addFilter(f2);
scan.setFilter(filterList);
ResultScanner results = table.getScanner(scan);

具体使用案例

package hbasetest2;
import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HbaseConfiguration;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Operation;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.filter.CompareFilter.*;
import org.apache.hadoop.hbase.filter.FilterList.Operator;

import com.sun.xml.bind.v2.schemagen.xmlschema.List;

import java.util.ArrayList;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;

public class HbaseJavaProgramme {
	
//statement global variable
public static Configuration configuration;
public static Connection connection;
public static Admin admin;
public static Table table;

public static void main(String[] args) {
	// TODO Auto-generated method stub
	
	try {
		
		//create configuration
		configuration = HbaseConfiguration.create();
		configuration.set("hbase.zookeeper.quorum", "localhost");
		configuration.set("hbase.zookeeper.property.clientPort", "2181");
		//create connection
		connection = ConnectionFactory.createConnection(configuration);
		
		//create table
		String[] families = {"StuInfo","Grades"};
		createTable("stu2", families);
		
		//read csv and create put object
		ArrayList puts = FileOperation.readData("/home/tarena/stuData.csv");
		
		//insert data
		table = connection.getTable(TableName.valueOf("stu2"));
		table.put(puts);
		table.close();
		System.out.println("insert data completed!");
		
		
		//scan data
		scanData("stu2");
		
		//scan data with filter
		scanDataWithFilter("stu2","6","24");//行键>=6 年龄<24
		
		
		connection.close();
		
	}catch (Exception e) {
		// TODO: handle exception
		e.printStackTrace();
	}
	
	
}



//create table stu2
public static void createTable(String tableString,String[] families) throws Exception{
	
	admin = connection.getAdmin();
	TableName tableName = TableName.valueOf(tableString);
	
	if(admin.tableExists(tableName)) {
		admin.disableTable(tableName);
		admin.deleteTable(tableName);
	}
	
	HTableDescriptor tdesc = new HTableDescriptor(tableName);
	//add family
	for(String family:families) {
		tdesc.addFamily(new HColumnDescriptor(family.getBytes()));
	}
	
	admin.createTable(tdesc);
	
	admin.close();
	
}

//scan data of table stu2
public static void scanData(String tableNameString) throws Exception{
	TableName tableName = TableName.valueOf(tableNameString);
	table = connection.getTable(tableName);
	
	Scan scan = new Scan();
	
	ResultScanner resultScanner = table.getScanner(scan);
	
	for(Result result:resultScanner) {
		for(Cell cell:result.rawCells()) {
			parseCell(cell);
		}
	}
	
	table.close();
	
}

//scan data of table stu2 with filters
public static void scanDataWithFilter(String tableNameString,String rowString,String valueString) throws Exception{
	
	TableName tableName = TableName.valueOf(tableNameString);
	table = connection.getTable(tableName);
	
	Scan scan = new Scan();
	Filter f1 = new RowFilter(CompareOp.GREATER_OR_EQUAL, new BinaryComparator(rowString.getBytes()));
	Filter f2 = new SingleColumnValueFilter("StuInfo".getBytes(), "Age".getBytes(), CompareOp.LESS, new BinaryComparator(valueString.getBytes()));
	FilterList filterList = new FilterList(f1,f2);//AND
	FilterList filterList2 = new FilterList(Operator.MUST_PASS_ALL);//AND过滤
	filterList2.addFilter(f1);
	filterList2.addFilter(f2);

	scan.setFilter(filterList);
	
	ResultScanner resultScanner = table.getScanner(scan);
	
	for(Result result:resultScanner) {
		for(Cell cell:result.rawCells()) {
			System.out.println("");
			parseCell(cell);
		}
	}
	
	table.close();
	
}

//parse Cell
public static void parseCell(Cell cell) throws Exception{
	System.out.println("行键:"+ new String(CellUtil.cloneRow(cell)));
	System.out.println("列族:"+ new String(CellUtil.cloneFamily(cell)));
	System.out.println("列标识:"+ new String(CellUtil.cloneQualifier(cell)));
	System.out.println("值:"+ new String(CellUtil.clonevalue(cell)) + "n");
}



}

大数据技术----HBase Jave编程

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