20201121-大数据-07

1.列出Hbase所有的表的相关信息，如表名：

2.在终端打印出指定表的所有记录数据

3.向已经创建好的表添加和删除指定的列族或列

4.清空指定表的所有记录数据

5.统计表的行数

关系型数据库中的表和数据（教材P92上)，要求将其转换为适合于HBase存储的表并插入数据。

编程完成以下指定功能（教材P92下)：

（1）createTable(String tableName, String[] fields)创建表。

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;

public class F_createTable {
public static Configuration configuration;
public static Connection connection;
public static Admin admin;

public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
createTable("Score",new String[]{"sname","course"});

}
//建立连接
public static void init(){
configuration = HBaseConfiguration.create();
configuration.set("hbase.rootdir","hdfs://localhost:9000/hbase");
try{
connection = ConnectionFactory.createConnection(configuration);
admin = connection.getAdmin();
}catch (IOException e){
e.printStackTrace();
}
}
//关闭连接
public static void close(){
try{
if(admin != null){
admin.close();
}
if(null != connection){
connection.close();
}
}catch (IOException e){
e.printStackTrace();
}
}
public static void createTable(String myTableName,String[] colFamily) throws IOException {

init();
TableName tableName = TableName.valueOf(myTableName);

if(admin.tableExists(tableName)){
deleteTable(tableName.getNameAsString());
System.out.println("talbe is exists,it will be deleted");
}else {
HTableDescriptor hTableDescriptor = new HTableDescriptor(tableName);
for(String str:colFamily){
HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(str);
hTableDescriptor.addFamily(hColumnDescriptor);
}
admin.createTable(hTableDescriptor);
System.out.println("create table success");
}
close();
}

public static void deleteTable(String tableName) throws IOException {
init();
TableName tn = TableName.valueOf(tableName);
if (admin.tableExists(tn)) {
admin.disableTable(tn);
admin.deleteTable(tn);
}
close();
}
}

（2）addRecord(String tableName, String row, String[] fields, String[] values)

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Table;

public class G_addRecord {
public static Configuration configuration;
public static Connection connection;
public static Admin admin;

public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
addRecord("student", "2015003", new String[]{"info:S_age"}, "99");
B_getAllData show = new B_getAllData();
show.getTableData("student");
}
//建立连接
public static void init(){
configuration = HBaseConfiguration.create();
configuration.set("hbase.rootdir","hdfs://localhost:9000/hbase");
try{
connection = ConnectionFactory.createConnection(configuration);
admin = connection.getAdmin();
}catch (IOException e){
e.printStackTrace();
}
}
//关闭连接
public static void close(){
try{
if(admin != null){
admin.close();
}
if(null != connection){
connection.close();
}
}catch (IOException e){
e.printStackTrace();
}
}
public static void addRecord(String tableName,String rowKey,String cols[],String val) throws IOException {
init();
Table table = connection.getTable(TableName.valueOf(tableName));
for(String str:cols)
{
String[] cols_split = str.split(":");
Put put = new Put(rowKey.getBytes());
put.addColumn(cols_split[0].getBytes(), cols_split[1].getBytes(), val.getBytes());
table.put(put);
}
table.close();
close();
}

}

（3）scanColumn(String tableName, String column)

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;

public class H_scanColumn {
public static Configuration configuration;
public static Connection connection;
public static Admin admin;

public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
scanColumn("SC","SC_score");
}
//建立连接
public static void init(){
configuration = HBaseConfiguration.create();
configuration.set("hbase.rootdir","hdfs://localhost:9000/hbase");
try{
connection = ConnectionFactory.createConnection(configuration);
admin = connection.getAdmin();
}catch (IOException e){
e.printStackTrace();
}
}
//关闭连接
public static void close(){
try{
if(admin != null){
admin.close();
}
if(null != connection){
connection.close();
}
}catch (IOException e){
e.printStackTrace();
}
}

public static void scanColumn(String tablename,String col) throws IOException {
init();
HTableDescriptor hTableDescriptors[] = admin.listTables();
String[] cols_split = col.split(":");
System.out.println(tablename);
Table table = connection.getTable(TableName.valueOf(tablename));
Scan scan1 = new Scan();
ResultScanner scanner1 = table.getScanner(scan1);
for (Result res : scanner1) {
Cell[] cells = res.rawCells();
for(Cell cell:cells){
String colF = new String(CellUtil.cloneFamily(cell));
String col_son = new String(CellUtil.cloneQualifier(cell));
//System.out.println(colF+" "+col_son+" "+cols_split[0]+" "+cols_split[1]);
if((colF.equals(cols_split[0])&&cols_split.length==1)||(colF.equals(cols_split[0])&&col_son.equals(cols_split[1])))
System.out.println(new String(CellUtil.cloneRow(cell))+" "+new String(CellUtil.cloneFamily(cell))+" "+new String(CellUtil.cloneQualifier(cell))+" "+new String(CellUtil.cloneValue(cell))+" ");
}
}
//关闭释放资源
scanner1.close();
table.close();
close();
}

}

（4）modifyData(String tableName, String row, String column)

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Table;

public class I_modifyData {
public static Configuration configuration;
public static Connection connection;
public static Admin admin;


public static void main(String[] args) throws IOException {
// TODO Auto-generated method stub
modifyData("student","2015003","info:S_name","Sunxiaochuan");
B_getAllData show = new B_getAllData();
show.getTableData("student");
}
//建立连接
public static void init(){
configuration = HBaseConfiguration.create();
configuration.set("hbase.rootdir","hdfs://localhost:9000/hbase");
try{
connection = ConnectionFactory.createConnection(configuration);
admin = connection.getAdmin();
}catch (IOException e){
e.printStackTrace();
}
}
//关闭连接
public static void close(){
try{
if(admin != null){
admin.close();
}
if(null != connection){
connection.close();
}
}catch (IOException e){
e.printStackTrace();
}
}

public static void modifyData(String tableName,String rowKey,String col,String val) throws IOException {
init();
Table table = connection.getTable(TableName.valueOf(tableName));
Put put = new Put(rowKey.getBytes());
String[] cols_split = col.split(":");
if(cols_split.length==1)
{
cols_split = insert(cols_split,"");
}
put.addColumn(cols_split[0].getBytes(), cols_split[1].getBytes(), val.getBytes());
table.put(put);
table.close();
close();
}
//I_
private static String[] insert(String[] arr, String str) {
int size = arr.length; //获取数组长度
String[] tmp = new String[size + 1]; 
for (int i = 0; i < size; i++){
tmp[i] = arr[i];
}
tmp[size] = str; 
return tmp;
}
}

（5）deleteRow(String tableName, String row)

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;

public class J_deleteRow {
public static Configuration configuration;
public static Connection connection;
public static Admin admin;

public static void main(String[] args) throws IOException {
B_getAllData show = new B_getAllData();
show.getTableData("student");
deleteRow("student", "2015003");
show.getTableData("student");
// TODO Auto-generated method stub

}
//建立连接
public static void init(){
configuration = HBaseConfiguration.create();
configuration.set("hbase.rootdir","hdfs://localhost:9000/hbase");
try{
connection = ConnectionFactory.createConnection(configuration);
admin = connection.getAdmin();
}catch (IOException e){
e.printStackTrace();
}
}
//关闭连接
public static void close(){
try{
if(admin != null){
admin.close();
}
if(null != connection){
connection.close();
}
}catch (IOException e){
e.printStackTrace();
}
}

public static void deleteRow(String tableName,String rowKey) throws IOException {
init();
Table table = connection.getTable(TableName.valueOf(tableName));
Delete delete = new Delete(rowKey.getBytes());
table.delete(delete);
table.close();
close();
}
}

20201121-大数据-07

原文：https://www.cnblogs.com/HzYul/p/14017025.html