hbase基础的增删查改

table 自行更改包名

package table;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import java.io.IOException;

student 自行更改类名

public class student{
    public static Configuration configuration;
    public static Connection connection;
    public static Admin admin;
 
    //主函数中的语句请逐句执行,只需删除其前的//即可,如:执行insertRow时请将其他语句注释
    public static void main(String[] args)throws IOException{
        创建一个表,表名为mxy,列族为name,age,sex,course
        //  createTable("mxy",new String[]{"name","age","sex","course"});
 
        //在Score表中插入一条数据,其行键为95001,sname为Mary(因为sname列族下没有子列所以第四个参数为空)
        //等价命令:put 'Score','95001','sname','Mary'   //在终端运行的命令
       insertRow("mxy", "95001", "name","","mxy");
        //在Score表中插入一条数据,其行键为95001,course:Math为88(course为列族,Math为course下的子列)
        //等价命令:put 'Score','95001','score:Math','88'
        insertRow("mxy", "95001", "age", "", "18");
        //在Score表中插入一条数据,其行键为95001,course:English为85(course为列族,English为course下的子列)
        //等价命令:put 'Score','95001','score:English','85'
        insertRow("mxy", "95003", "course", "English", "85");
    	insertRow("mxy", "95002", "course", "Math", "59");
 
        //1、删除Score表中指定列数据,其行键为95001,列族为course,列为Math
        //执行这句代码前请deleteRow方法的定义中,将删除指定列数据的代码取消注释注释,将删除制定列族的代码注释
        //等价命令:delete 'Score','95001','score:Math'
        //deleteRow("Score", "95001", "course", "Math");
 
        //2、删除Score表中指定列族数据,其行键为95001,列族为course(95001的Math和English的值都会被删除)
        //执行这句代码前请deleteRow方法的定义中,将删除指定列数据的代码注释,将删除制定列族的代码取消注释
        //等价命令:delete 'Score','95001','score'
        //deleteRow("mxy", "95001", "course", "");
 
        //3、删除Score表中指定行数据,其行键为95001
        //执行这句代码前请deleteRow方法的定义中,将删除指定列数据的代码注释,以及将删除制定列族的代码注释
        //等价命令:deleteall 'Score','95001'
        //deleteRow("mxy", "95001","","");
 
        //查询Score表中,行键为95001,列族为course,列为Math的值
        //getData("mxy", "95001", "course", "Math");
        //查询Score表中,行键为95001,列族为sname的值(因为sname列族下没有子列所以第四个参数为空)
        //getData("mxy", "95001","course","");
 
        //删除mxy表
        //deleteTable("mxy");

        // 追加插入(将原有value的后面追加新的value,如原有value=a追加value=bc则最后的value=abc)
    	//appendData("mxy","95003","course","English","1");
        
        //全局扫描显示
    	scanTable("mxy");
    	
    }

全局扫描显示

    /**
	 * 全表扫描
	 * @param result
	 */
	public static void scanTable(String tableName) throws IOException {
    init();
    Table table = connection.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());
        }
    }
}
	 // 追加插入(将原有value的后面追加新的value,如原有value=a追加value=bc则最后的value=abc)
    public static void appendData(String tableName, String rowKey, String columnFamily, String column, String value) 
            throws IOException {
    	init();
        // 获取表
    	 Table table = connection.getTable(TableName.valueOf(tableName));
        // 通过rowkey创建一个append对象
        Append append = new Append(rowKey.getBytes());
        // 在append对象中设置列族、列、值
        append.add(columnFamily.getBytes(), column.getBytes(), value.getBytes());
        // 追加数据
        table.append(append);
        // 关闭资源
        table.close();

    }
//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();
        }
    }
 
    /**
     * 建表。HBase的表中会有一个系统默认的属性作为主键,主键无需自行创建,默认为put命令操作中表名后第一个数据,因此此处无需创建id列
     * @param myTableName 表名
     * @param colFamily 列族名
     * @throws IOException
     */
    public static void createTable(String myTableName,String[] colFamily) throws IOException {
 
        init();
        TableName tableName = TableName.valueOf(myTableName);
 
        if(admin.tableExists(tableName)){
            System.out.println("talbe is exists!");
        }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();
    }
    /**
	     * 删除指定表
	     * @param tableName 表名
	     * @throws IOException
	     */
	    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();
	    }
	 
	    /**
	     * 查看已有表
	     * @throws IOException
	     */
	    public static void listTables() throws IOException {
	        init();
	        HTableDescriptor hTableDescriptors[] = admin.listTables();
	        for(HTableDescriptor hTableDescriptor :hTableDescriptors){
	            System.out.println(hTableDescriptor.getNameAsString());
	        }
	        close();
	    }
	    /**
	     * 向某一行的某一列插入数据
	     * @param tableName 表名
	     * @param rowKey 行键
	     * @param colFamily 列族名
	     * @param col 列名(如果其列族下没有子列,此参数可为空)
	     * @param val 值
	     * @throws IOException
	     */
	    public static void insertRow(String tableName,String rowKey,String colFamily,String col,String val) throws IOException {
	        init();
	        Table table = connection.getTable(TableName.valueOf(tableName));
	        Put put = new Put(rowKey.getBytes());
	        put.addColumn(colFamily.getBytes(), col.getBytes(), val.getBytes());
	        table.put(put);
	        table.close();
	        close();
	    }
	 
	    /**
	     * 删除数据
	     * @param tableName 表名
	     * @param rowKey 行键
	     * @param colFamily 列族名
	     * @param col 列名
	     * @throws IOException
	     */
	    public static void deleteRow(String tableName,String rowKey,String colFamily,String col) throws IOException {
	        init();
	        Table table = connection.getTable(TableName.valueOf(tableName));
	        Delete delete = new Delete(rowKey.getBytes());
	        //删除指定列族的所有数据
	        //delete.addFamily(colFamily.getBytes());
	        //删除指定列的数据
	        //delete.addColumn(colFamily.getBytes(), col.getBytes());
	 
	        table.delete(delete);
	        table.close();
	        close();
	    }
	    /**
	     * 根据行键rowkey查找数据
	     * @param tableName 表名
	     * @param rowKey 行键
	     * @param colFamily 列族名
	     * @param col 列名
	     * @throws IOException
	     */
	    public static void getData(String tableName,String rowKey,String colFamily,String col)throws  IOException{
	        init();
	        Table table = connection.getTable(TableName.valueOf(tableName));
	        Get get = new Get(rowKey.getBytes());
	        get.addColumn(colFamily.getBytes(),col.getBytes());
	        Result result = table.get(get);
	        showCell(result);
	        table.close();
	        close();
	    }
	    /**
	     * 格式化输出
	     * @param result
	     */
	    public static void showCell(Result result){
	        Cell[] cells = result.rawCells();
	        for(Cell cell:cells){
	            System.out.println("RowName:"+new String(CellUtil.cloneRow(cell))+" ");
	            System.out.println("Timetamp:"+cell.getTimestamp()+" ");
	            System.out.println("column Family:"+new String(CellUtil.cloneFamily(cell))+" ");
	            System.out.println("row Name:"+new String(CellUtil.cloneQualifier(cell))+" ");
	            System.out.println("value:"+new String(CellUtil.cloneValue(cell))+" ");
	        }
	    }		

	}

猜你喜欢

转载自blog.csdn.net/weixin_41215479/article/details/84578393