HbaseApi

@Version V1.0
**/
public class TestApi {

// 声明链接
private static Connection connection = null;
// 声明管理员对象
private static Admin admin = null;

// 初始化
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();
}
}

• 释放资源
• @throws IOException
  */
  private static void close() throws IOException {
  if (admin != null) {
  admin.close();
  }
  if (connection != null) {
  connection.close();
  }
  }

• 判断表是否存在
• @param tableName
• @return
• @throws IOException
  */
  public static boolean isTableExsit(String tableName) throws IOException {
  boolean exists = admin.tableExists(TableName.valueOf(tableName));
  return exists;
  }

• 创建表
• @param tableName
• @param cf
  */
  public static void createTable(String tableName, String... cf) throws IOException {
  if (isTableExsit(tableName)) {
  // new IllegalArgumentException("表已经存在,在点我就报警了!");
  System.out.println("表已经存在,在点我就报警了!");
  return;
  }
  if (cf.length System.out.println("参数异常!");
  return;
  }
  HTableDescriptor descriptor = new HTableDescriptor(TableName.valueOf(tableName));
  for (String s : cf) {
  HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(s);
  descriptor.addFamily(hColumnDescriptor);
  }
  admin.createTable(descriptor);
  }

• 删除表
• @param tableName
• @throws IOException
  */
  public static void deleteTable(String tableName) throws IOException {
  if (!isTableExsit(tableName)) {
  System.out.println("表不存在!");
  return;
  }
  admin.disableTable(TableName.valueOf(tableName));
  admin.deleteTable(TableName.valueOf(tableName));
  }

• 创建命名空间
• @param nameSpace
• @throws IOException
  */
  public static void createNameSpace(String nameSpace) throws IOException {
  try {
  NamespaceDescriptor build = NamespaceDescriptor.create(nameSpace).build();
  admin.createNamespace(build);
  } catch (NamespaceExistException e) {
  System.out.println(nameSpace + "此命名空间已经存在!");
  } catch (IOException e) {
  e.printStackTrace();
  }
  }

// =====================================>我是华丽分割线===================================>

• 添加数据
• @param tableName
• @param cf
• @param cn
• @param value
  */
  public static void put(String tableName, String rk, String cf, String cn, String value) throws IOException {
  // 创建表对象
  Table table = connection.getTable(TableName.valueOf(tableName));
  // 声明put对象
  Put putObject = new Put(Bytes.toBytes(rk));
  // 向put对象中添加值
  putObject.addColumn(Bytes.toBytes(cf), Bytes.toBytes(cn), Bytes.toBytes(value));
  // putObject.addColumn(Bytes.toBytes("info"), Bytes.toBytes("sex"), Bytes.toBytes("female"));
  // 向表中添加数据
  table.put(putObject);
  // 关闭
  table.close();
  }

• 查询数据 ---》 get
• @param tableName
• @param rk
• @throws IOException
  */
  public static void get(String tableName, String rk) throws IOException {
  // 1. 获取对象
  Table table = connection.getTable(TableName.valueOf(tableName));
  // 2. 获得get对象
  Get getObject = new Get(Bytes.toBytes(rk));
  // 3. 获取查询结果
  Result result = table.get(getObject);
  // 4. 遍历获取单个cell并打印
  for (Cell cell : result.rawCells()) {
  System.out.println("RK : " + Bytes.toString(CellUtil.cloneRow(cell)) +
  ", CF : " + Bytes.toString(CellUtil.cloneFamily(cell)) +
  ", CN : " + Bytes.toString(CellUtil.cloneQualifier(cell)) +
  ", Value : " + Bytes.toString(CellUtil.cloneValue(cell)));
  }
  // 5. 释放资源
  table.close();
  }

• 查询数据 ---> scan
• @param tableName
• @throws IOException
  */
  public static void scan(String tableName) throws IOException {
  // 1. 获取表对象
  Table table = connection.getTable(TableName.valueOf(tableName));
  // 2. 创建Scan对象
  Scan scanObject = new Scan(Bytes.toBytes("1001"), Bytes.toBytes("1003"));
  // 3. 查询数据并获取结果
  ResultScanner scanner = table.getScanner(scanObject);
  // 4. 遍历
  for (Result result : scanner) {
  for (Cell cell : result.rawCells()) {
  System.out.println("RK : " + Bytes.toString(CellUtil.cloneRow(cell)) +
  ", CF : " + Bytes.toString(CellUtil.cloneFamily(cell)) +
  ", CN : " + Bytes.toString(CellUtil.cloneQualifier(cell)) +
  ", Value : " + Bytes.toString(CellUtil.cloneValue(cell)));
  }
  }
  // 5. 释放资源
  table.close();
  }

• 删除数据 ---> delete
• @param tableName
• @param rk
  */
  public static void delete(String tableName, String rk) throws IOException {
  // 1. 获取表对象
  Table table = connection.getTable(TableName.valueOf(tableName));
  // 2. 执行删除逻辑
  Delete deleteObject = new Delete(Bytes.toBytes(rk));
  table.delete(deleteObject);
  // 2. 释放资源
  table.close();
  }

• 测试Api
• @param args
  */
  public static void main(String[] args) throws IOException {
  // 1. 测试表是否存在
  // System.out.println(isTableExsit("employee"));
  // 2. 创建表
  // createTable("user", "info", "name");
  // 3. 删除表
  // deleteTable("user");
  // 4. 创建命名空间
  // createNameSpace("1703");
  // 5. 插入数据
  // put("user", "1003", "info", "name", "qiaoyuan2");
  // 6. 查询数据 get
  // get("user", "1001");
  // 7. 查询数据 scan
  // scan("user");
  // 8. 删除数据 delete
  delete("user", "1003");
  // 释放资源
  close();
  }
  }