• hbase安装之hbase的api操作


    package test;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.hbase.*;
    import org.apache.hadoop.hbase.client.*;
    import org.apache.hadoop.hbase.util.Bytes;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    
    @WebServlet("/hbaseServlet")
    public class hbase extends HttpServlet {
        private static Connection connection=null;
        private static Admin admin=null;
    
        static {
            try {
                Configuration configuration = HBaseConfiguration.create();
                configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");
                connection= ConnectionFactory.createConnection(configuration);
                admin=connection.getAdmin();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        //1.判断表是否存在
        public static boolean isTableExist(String tableName) throws IOException {
    //        //1.获取配置文件信息
    //        //HBaseConfiguration configuration = new HBaseConfiguration();
    //        Configuration configuration = HBaseConfiguration.create();
    //        configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");
    //
    //        //2.获取管理员对象
    //        //HBaseAdmin admin = new HBaseAdmin(configuration);
    //        Connection connection = ConnectionFactory.createConnection(configuration);
    //        Admin admin = connection.getAdmin();
            //3.判断表是否存在
            boolean exists=admin.tableExists(TableName.valueOf(tableName));
            //4.关闭连接
    //        admin.close();
            return exists;
        }
        //2.创建表
        public static void createTable(String tableName,String... cfs) throws IOException {
            //1.判断是否存在列族信息
            if(cfs.length<=0){
                System.out.println("列族信息为空");
                return;
            }
            //2.判断表是否存在
            if(isTableExist(tableName)){
                System.out.println("表存在");
                return;
            }
            //3.创建表描述器
            HTableDescriptor hTableDescriptor = new HTableDescriptor(TableName.valueOf(tableName));
            //4.循环添加列族信息
            for(String cf:cfs){
                //5.创建列族描述器
                HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(cf);
                //6.添加具体列族信息
                hTableDescriptor.addFamily(hColumnDescriptor);
            }
            //7.创建表
            admin.createTable(hTableDescriptor);
        }
        //3.删除表
        public static void dropTable(String tableName) throws IOException {
            //1.判断表是否存在
            if(!isTableExist(tableName)){
                System.out.println("表不存在");
                return;
            }
            //2.使表下线
            admin.disableTable(TableName.valueOf(tableName));
            //3.删除表
            admin.deleteTable(TableName.valueOf(tableName));
        }
        //4.创建命名空间
        public static void createNameSpace(String ns){
            //1.创建命名空间描述器
            NamespaceDescriptor namespaceDescriptor = NamespaceDescriptor.create(ns).build();
            //2.创建命名空间
            try {
                admin.createNamespace(namespaceDescriptor);
            }catch (NamespaceExistException e){
                System.out.printf(ns+"命名空间存在");
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        //关闭连接
        public static void close(){
            if(admin!=null){
                try {
                    admin.close();
                }
                catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if(connection!=null){
                try {
                    connection.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        //5.向表中插入数据
        public static void putData(String tableName,String rowKey,String cf,String cn,String value) throws IOException {
            //1.获取表对象呢
            Table table = connection.getTable(TableName.valueOf(tableName));
            //2.创建put对象(添加多行,则创建多个put对象)
            Put put = new Put(Bytes.toBytes(rowKey));
            //3.给put对象赋值(同一个put对象可以添加多个列)
            put.addColumn(Bytes.toBytes(cf),Bytes.toBytes(cn),Bytes.toBytes(value));
            //4.插入数据
            table.put(put);
            //5.关闭表连接
    
        }
        //6.获取数据get
        public static void getData(String tableName,String rowKey,String cf,String cn) throws IOException {
            //1.获取表对象
            Table table = connection.getTable(TableName.valueOf(tableName));
            //2.创建get对象
            Get get = new Get(Bytes.toBytes(rowKey));
            //2.1指定获取的列族
            //get.addFamily(Bytes.toBytes(cf));
            //2.2指定列族和列
            //get.addColumn(Bytes.toBytes(cf),Bytes.toBytes(cn));
            //2.3获取数据的版本数
            //get.setMaxVersions();
            //3.获取数据
            Result result=table.get(get);
            //4.解析result
            for( Cell cell:result.rawCells()){
                //5.打印数据
                System.out.printf("CF:"+Bytes.toString(CellUtil.cloneFamily(cell))+
                        ",CN:"+Bytes.toString(CellUtil.cloneQualifier(cell))+
                        ",Value:"+Bytes.toString(CellUtil.cloneValue(cell)));
            }
            //6.关闭表连接
            table.close();
    
        }
        //7.获取数据scan
        public static void scanTable(String tableName) throws IOException {
            //1.获取表对象
            Table table = connection.getTable(TableName.valueOf(tableName));
            //2.构建scan对象
            Scan scan = new Scan(Bytes.toBytes("1001"));
            //3.扫描表
            ResultScanner resultScanner = table.getScanner(scan);
            //4.解析resultScanner
            for(Result result:resultScanner){
                //5.解析并打印
                for(Cell cell:result.rawCells()){
                    System.out.printf("RK:"+Bytes.toString(CellUtil.cloneRow(cell))+",CF:"+Bytes.toString(CellUtil.cloneFamily(cell))+
                            ",CN:"+Bytes.toString(CellUtil.cloneQualifier(cell))+
                            ",Value:"+Bytes.toString(CellUtil.cloneValue(cell)));
                }
            }
            table.close();
        }
        //8.删除数据
        public static void deleteData(String tableName,String rowKey,String cf,String cn) throws IOException {
            //1.获取表对象
            Table table = connection.getTable(TableName.valueOf(tableName));
            //2.构建删除对象
            Delete delete = new Delete(Bytes.toBytes(rowKey));//删除行
            //2.1设置删除的列
            //delete.addColumns(Bytes.toBytes(cf),Bytes.toBytes(cn));//不指定时间戳会删除所有
            //delete.addColumn(Bytes.toBytes(cf),Bytes.toBytes(cn));//不指定时间戳会删除最新的
            //2.2删除指定的列族
            //delete.addFamily(Bytes.toBytes(cf));
            //3.执行删除操作
            table.delete(delete);
            table.close();
        }
    
        public static void main(String[] args) throws IOException{
    
            //1.测试表是否存在
            System.out.println(isTableExist("stu5"));
    //        //2.创建表测试
    //        createTable("stu5","info1","info2");
    //        //3.删除表
    //        dropTable("stu5");
    //        System.out.println(isTableExist("stu5"));
    //        //4.插入数据
    //        putData("stu","1001","info2","sex","man");
    //        //5.获取单行数据
    //        getData("stu","1001","info2","name");
    //        //6.scan方法获取数据
    //        scanTable("stu");
            //7.删除
    //        deleteData("stu","1001","","");
    //        close();
        }
        @Override
        protected void doPost(HttpServletRequest req, HttpServletResponse resp)
                throws ServletException, IOException {
            // TODO Auto-generated method stub
            req.setCharacterEncoding("utf-8");
            resp.setCharacterEncoding("utf-8");
        }
        @Override
        protected void doGet(HttpServletRequest req, HttpServletResponse resp)
                throws ServletException, IOException
        {
            req.setCharacterEncoding("utf-8");
            resp.setCharacterEncoding("utf-8");
            String kjcxwt_cxfw=req.getParameter("kjcxwt_cxfw");
            String kjcxwt_cname=req.getParameter("kjcxwt_cname");
            String nov_purpose=req.getParameter("nov_purpose");
            String kjcxwt_cxyd=req.getParameter("kjcxwt_cxyd");
            String finishdate=req.getParameter("finishdate");
            String subject=req.getParameter("subject");
            String industry=req.getParameter("industry");
            String kjcxwt_memo=req.getParameter("kjcxwt_memo");
            System.out.printf(kjcxwt_cxfw+":"+kjcxwt_cname+":"+nov_purpose+":"+kjcxwt_cxyd+":"
                    +finishdate+":"+subject+":"+industry+":"+kjcxwt_memo);
    
        }
    }
        <dependency>
          <groupId>org.apache.hbase</groupId>
          <artifactId>hbase-client</artifactId>
          <version>1.3.1</version>
        </dependency>
        <dependency>
          <groupId>org.apache.hbase</groupId>
          <artifactId>hbase-server</artifactId>
          <version>1.3.1</version>
        </dependency>
  • 相关阅读:
    分布式消息系统Kafka初步
    webService 学习
    一个周末掌握IT前沿技术之node.js篇
    mount
    dd
    fsck
    resize2fs
    mkfs
    parted
    tune2fs
  • 原文地址:https://www.cnblogs.com/fengchuiguobanxia/p/15268718.html
Copyright © 2020-2023  润新知