一、功能
通过JAVA API实现数据库的创建表、删除表以及增删改查基本操作。
二、配置
1.Maven依赖
<repositories>
<repository>
<id>cloudera</id>
<url>https://repository.cloudera.com/artifactory/cloudera-repos/</url>
</repository>
</repositories>
<!-- https://mvnrepository.com/artifact/org.apache.hbase/hbase-client -->
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-client</artifactId>
<version>${hbase.version}</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.hbase/hbase-server -->
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-server</artifactId>
<version>${hbase.version}</version>
</dependency>2.java读取默认hbase-site.xml位置，但是需要程序中配置conf一些参数：
数据仓库\org\apache\hbase\hbase-common\1.2.0-cdh5.7.0\hbase-common-1.2.0-cdh5.7.0.jarjava配置参数
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");或者可以把hbase的hbase-site.xml拷贝到java项目的resources目录下面，这样就可以直接读取，而不用程序中配置参数。
三、具体操作java api
1.创建namespace和table
/**
* 1.创建namespace和table
* 参考hbase shell命令create 'namespace:tablename','column family1','column family1'
* @throws ZooKeeperConnectionException
* @throws MasterNotRunningException
*/
@SuppressWarnings("resource")
// @Test
public void createTable() throws Exception {
String nameSpace = "hadoop22";
String tbName = "actor";
String colFamily = "info";
// 1.读取配置文件
//默认读取的是："E:\Tools\apache-maven-3.3.9\Repository\org\apache\hbase\hbase-common\1.2.0-cdh5.7.0\hbase-common-1.2.0-cdh5.7.0.jar"中
//的hbase-default.xml，也可以把hbase-site.xml放到resources中
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");
// 2.创建一个管理员，管理表格的创建和删除
HBaseAdmin admin = new HBaseAdmin(conf);
// 3.创建命名空间描述器
NamespaceDescriptor ns = NamespaceDescriptor.create(nameSpace).build();
// 4.创建表格，表格对象
TableName tableName = TableName.valueOf(nameSpace + ":" + tbName);
// 创建表的描述器
HTableDescriptor tableDesc = new HTableDescriptor(tableName);
// 5.创建列簇的描述器
HColumnDescriptor columnDesc = new HColumnDescriptor(colFamily);
// 6.将列簇添加到表的描述器
tableDesc.addFamily(columnDesc);
// 7.创建命名空间，创建表
admin.createNamespace(ns);
admin.createTable(tableDesc);
System.out.println("创建表 " + nameSpace + ":" + tbName + " 成功");
}2.删除表
/**
* 2.删除表
*/
// @Test
public void deleteTable() throws Exception {
String nameSpace = "hadoop22";
String tbName = "actor";
// 读取配置文件
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");
// 创建一个管理员，管理表格的创建和删除
@SuppressWarnings("resource")
HBaseAdmin admin = new HBaseAdmin(conf);
// 创建表格对象
TableName tableName = TableName.valueOf(nameSpace + ":" + tbName);
// 删除操做
admin.disableTable(tableName);
admin.deleteTable(tableName);
System.out.println("表已经删除");
admin.deleteNamespace(nameSpace);
System.out.println("命名空间已经删除");
}
3.添加数据
/**
* 3.添加数据
* put 'namespace:tableName','rowKey','column falmily:column','value'
*/
// @Test
public void putData() throws Exception {
String nameSpace = "hadoop22";
String tbName = "actor";
String colFamily = "info";
String rowkey = "10086";// 10010
String column = "name";
String value = "李四3";
// 1.读取配置文件
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");
// 2.创建表对象
TableName tableName = TableName.valueOf(nameSpace + ":" + tbName);
@SuppressWarnings("resource")
HTable table = new HTable(conf, tableName);
// 3.创建put对象
Put put = new Put(Bytes.toBytes(rowkey));
// 4.获取所有的列簇，封装到数组中，然后进行判断
// 如果是该列簇下的，才插入到相应的列簇。所以需要判断
HColumnDescriptor[] columns = table.getTableDescriptor().getColumnFamilies();
for (int i = 0; i < columns.length; i++) {
String columnfamilys = columns[i].getNameAsString();
// 判断
if (columnfamilys.equals(colFamily)) {
// 添加数据
put.add(Bytes.toBytes(columnfamilys), Bytes.toBytes(column), Bytes.toBytes(value));
put.add(Bytes.toBytes(columnfamilys), Bytes.toBytes("age"), Bytes.toBytes("23"));
}
}
// 5.提交
table.put(put);
// 6.关闭资源0607update
table.close();
System.out.println("添加数据成功");
}4.删除数据
/**
* 4.删除数据
* delete 'namespace:tablename','rowkey','columnfamily:column'
*/
// @Test
public void deleteData() throws Exception {
String nameSpace = "hadoop22";
String tbName = "actor";
String colFamily = "info";
String rowkey = "10086";
String column = "name";
// 读取配置文件
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");
// 创建表对象
TableName tableName = TableName.valueOf(nameSpace + ":" + tbName);
@SuppressWarnings("resource")
HTable table = new HTable(conf, tableName);
// 创建delete对象
Delete del = new Delete(Bytes.toBytes(rowkey));
// 删除某列的数据
del.deleteColumn(Bytes.toBytes(colFamily), Bytes.toBytes(column));
// 删除某一行的数据,因为del对象已经指定了rowkey了，直接表调用就可以
// 提交
table.delete(del);
System.out.println("删除数据成功");
}5.查询数据get
/**
* 5.查询数据get
*/
// @Test
public void getData() throws Exception {
String nameSpace = "hadoop22";
String tbName = "actor";
String colFamily = "info";
String rowkey = "10086";
String column = "name";
// 读取配置文件
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");
// 创建表对象
TableName tableName = TableName.valueOf(nameSpace + ":" + tbName);
@SuppressWarnings("resource")
HTable table = new HTable(conf, tableName);
//创建get对象
Get get = new Get(Bytes.toBytes(rowkey)); //指定rowkey查询
//get.addFamily(Bytes.toBytes(colFamily)); //指定列簇查询
//get.addColumn(Bytes.toBytes(colFamily), Bytes.toBytes(column)); //指定列查询
Result result = table.get(get);
Cell[] cells = result.rawCells();
for (Cell cell : cells) {
System.out.println("列簇："+Bytes.toString(CellUtil.cloneFamily(cell)));
System.out.println("列："+Bytes.toString(CellUtil.cloneQualifier(cell)));
System.out.println("值："+Bytes.toString(CellUtil.cloneValue(cell)));
System.out.println("时间戳："+cell.getTimestamp());
}
}6.查询数据scan
/**
* 6.查询数据scan
*/
// @Test
public void scanData() throws Exception {
String nameSpace = "hadoop22";
String tbName = "actor";
// 读取配置文件
Configuration conf = HBaseConfiguration.create();
conf.set("hbase.rootdir","hdfs://hadoop:8020/hbase");
conf.set("hbase.zookeeper.quorum","hadoop");
conf.set("hbase.zookeeper.property.clientPort","2181");
// 创建表对象
TableName tableName = TableName.valueOf(nameSpace + ":" + tbName);
@SuppressWarnings("resource")
HTable table = new HTable(conf, tableName);
//创建scan对象
Scan scan = new Scan();
//【这两个为查询起始和终止位置，2018/6/7】
//scan.setStartRow(Bytes.toBytes("10010"));
//scan.setStopRow(Bytes.toBytes("10080"));
// *********************************
// 【update 20180607】
//查询那些Column列
// scan.addColumn(family, qualifier)
//查询那些family
// scan.addFamily(family)
// **********************************
ResultScanner resultScanner = table.getScanner(scan);
for (Result result : resultScanner) {
//打印每一条数据
System.out.println("rowkey："+Bytes.toString(result.getRow()));
//result.rawCells()得到一行的所有单元格
for (Cell cell :result.rawCells() ) {
System.out.println("列簇："+Bytes.toString(CellUtil.cloneFamily(cell)));
System.out.println("列："+Bytes.toString(CellUtil.cloneQualifier(cell)));
System.out.println("值："+Bytes.toString(CellUtil.cloneValue(cell)));
System.out.println("时间戳："+cell.getTimestamp());
}
System.out.println("----------------------------------------");
}
}