linux 下通过过 hbase 的Java api 操作hbase
hbase版本:0.98.5
hadoop版本:1.2.1
使用自带的zk
本文的内容是在集群中创建java项目调用api来操作hbase,主要涉及对hbase的创建表格,删除表格,插入数据,删除数据,查询一条数据,查询所有数据等操作。
具体流程如下:
1.创建项目
2.获取jar包到项目的lib目录下(这边试用的事hbase 0.98 lib目录下的所有jar包)
3.编写java程序
4.编写ant脚本
package test2; import java.util.ArrayList; import java.util.List; import org.apache.hadoop.fs.Path; 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.HColumnDescriptor; import org.apache.hadoop.hbase.HTableDescriptor; import org.apache.hadoop.hbase.TableName; import org.apache.hadoop.hbase.client.Delete; import org.apache.hadoop.hbase.client.Get; import org.apache.hadoop.hbase.client.HBaseAdmin; import org.apache.hadoop.hbase.client.HConnection; import org.apache.hadoop.hbase.client.HConnectionManager; import org.apache.hadoop.hbase.client.HTable; 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.client.Scan; public class TestHBase { private HBaseAdmin admin = null; private Configuration conf = null; public TestHBase() throws Exception { conf = HBaseConfiguration.create(); conf.addResource(new Path("/home/work/hbase_dev/test2/lib/hbase-site.xml")); //conf.set("hbase.zookeeper.quorum", "10.57.90.19"); //conf.set("hbase.zookeeper.property.clientPort", "2181"); admin = new HBaseAdmin(conf); } public void createTable (String tableName , String[] columnFamily) throws Exception { if (admin.tableExists(tableName)) { System.out.println(tableName + "已存在"); return ; //System.exit(0); } HTableDescriptor tableDescriptor = new HTableDescriptor(TableName.valueOf(tableName)); for (String colunm : columnFamily) { tableDescriptor.addFamily(new HColumnDescriptor(colunm)); } admin.createTable(tableDescriptor); System.out.println("Create table successfully.."); } public boolean deleteTable (String tableName) { try { if(admin.tableExists(tableName)) { admin.disableTable(tableName); admin.deleteTable(tableName); System.out.println("drop table " + tableName); } return true; } catch (Exception e) { System.out.println("删除" + tableName + "失败"); return false; } } public List getAllTables() { List<String> tables = null; if (admin != null) { try{ HTableDescriptor[] allTables = admin.listTables(); if(allTables.length > 0) { tables = new ArrayList<String>(); } for (HTableDescriptor tableDesc : allTables) { tables.add(tableDesc.getNameAsString()); System.out.println(tableDesc.getNameAsString()); } }catch(Exception ex) { ex.printStackTrace(); } } return tables; } public boolean addOneRecord (String tableName , String key , String family , String column , byte[] dataIn) throws Exception { HConnection connection = HConnectionManager.createConnection(conf); //HTable table = new HTable(hbaseConf, tableName); HTable table = (HTable)connection.getTable(tableName); Put put = new Put(key.getBytes()); put.add(family.getBytes(), column.getBytes(), dataIn); try { table.put(put); System.out.println("插入数据条 " + key + "成功"); return true; } catch (Exception e) { // TODO: handle exception System.out.println("插入数据条 " + key + "失败"); return false; } } public void getValueFromKey (String tableName , String key) { try{ HConnection conn = HConnectionManager.createConnection(conf); HTable table = (HTable) conn.getTable(tableName); Get get = new Get(key.getBytes()); Result rs = table.get(get); if (rs.rawCells().length == 0) { System.out.println("不存在关键字为" + key + "的行..."); } else { for (Cell cell : rs.rawCells()) { System.out.println(new String(CellUtil.cloneFamily(cell)) + " " + new String(CellUtil.cloneQualifier(cell)) + " " + new String(CellUtil.cloneValue(cell))); } } } catch(Exception ex) { System.out.println("查询失败"); ex.printStackTrace(); } } public void getAllData(String tableName) throws Exception { HConnection conn = HConnectionManager.createConnection(conf); HTable table = (HTable) conn.getTable(tableName); Scan scan = new Scan(); ResultScanner rs = table.getScanner(scan); for (Result result : rs) { for (Cell cell : result.rawCells()) { 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)) + " "); } } } public void deleteRecord(String tableName , String key) { try { HConnection conn = HConnectionManager.createConnection(conf); HTable table = (HTable)conn.getTable(tableName); Delete delete = new Delete(key.getBytes()); table.delete(delete); System.out.println("删除" + key +"成功..."); } catch(Exception ex) { System.out.println("删除数据失败..."); ex.printStackTrace(); } } public static void main(String[] args) throws Exception{ // TODO Auto-generated method stub String[] column = {"family1" , "family2"}; try { TestHBase hbase = new TestHBase(); hbase.deleteTable("students"); hbase.createTable("students", column); //hbase.getAllData("scores"); hbase.addOneRecord("students", "id1", "family1", "name", "Jack".getBytes()); hbase.addOneRecord("students", "id1", "family1", "grade", "gaosan".getBytes()); //hbase.getAllTables(); //hbase.getAllData("students"); hbase.getValueFromKey("students", "id1"); hbase.deleteRecord("students", "id1"); hbase.addOneRecord("students", "id2", "family1", "name", "Holen".getBytes()); hbase.getValueFromKey("students", "id2"); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } }
ant脚本
<?xml version="1.0"?> <project name="HBaseProject" default="run" basedir="."> <property name="src.dir" value="src" /> <property name="report.dir" value="report" /> <property name="classes.dir" value="classes" /> <property name="lib.dir" value="lib" /> <property name="dist.dir" value="dist" /> <property name="doc.dir" value="doc"/> <path id="master-classpath"> <fileset file="${lib.dir}/*.jar" /> <pathelement path="${classes.dir}"/> </path> <path id="run.path"> <path path="${classes.dir}"/> <path refid="master-classpath" /> </path> <target name="init" depends="clean"> <mkdir dir="${classes.dir}"/> <mkdir dir="${dist.dir}"/> </target> <target name="compile" depends="init" description="compile the source files"> <javac srcdir="${src.dir}" destdir="${classes.dir}" target="1.6" includeantruntime="false"> <classpath refid="master-classpath"/> </javac> </target> <target name="run" depends="compile"> <java classname="test2.TestHBase" classpathref="run.path" fork="true" > </java> </target> <target name="pack" depends="compile" description="make .jar file"> <mkdir dir="${dist.dir}" /> <jar destfile="${dist.dir}/hbaseproject.jar" basedir="${classes.dir}"> <exclude name="**/*Test.*" /> <exclude name="**/Test*.*" /> </jar> </target> <target name="clean" description="clean the project"> <delete dir="${classes.dir}"></delete> <delete dir="${dist.dir}"></delete> </target> </project>
最后把项目放在集群中,进入项目的根目录,执行命令:ant run
即可运行!
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