Java API 与HBase交互实例 （总结11）

HBase提供了Java Api的访问接口，掌握这个就跟Java应用使用RDBMS时需要JDBC一样重要

    import java.io.IOException;            import org.apache.hadoop.conf.Configuration;      import org.apache.hadoop.hbase.HBaseConfiguration;      import org.apache.hadoop.hbase.HColumnDescriptor;      import org.apache.hadoop.hbase.HTableDescriptor;      import org.apache.hadoop.hbase.KeyValue;      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.HTable;      import org.apache.hadoop.hbase.client.HTablePool;      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;      import org.apache.hadoop.hbase.util.Bytes;            public class Hbase {          // 声明静态配置          static Configuration conf = null;          static {              conf = HBaseConfiguration.create();              conf.set("hbase.zookeeper.quorum", "localhost");          }                /*           * 创建表           *            * @tableName 表名           *            * @family 列族列表           */          public static void creatTable(String tableName, String[] family)                  throws Exception {              HBaseAdmin admin = new HBaseAdmin(conf);              HTableDescriptor desc = new HTableDescriptor(tableName);              for (int i = 0; i < family.length; i++) {                  desc.addFamily(new HColumnDescriptor(family[i]));              }              if (admin.tableExists(tableName)) {                  System.out.println("table Exists!");                  System.exit(0);              } else {                  admin.createTable(desc);                  System.out.println("create table Success!");              }          }                /*           * 为表添加数据（适合知道有多少列族的固定表）           *            * @rowKey rowKey           *            * @tableName 表名           *            * @column1 第一个列族列表           *            * @value1 第一个列的值的列表           *            * @column2 第二个列族列表           *            * @value2 第二个列的值的列表           */          public static void addData(String rowKey, String tableName,                  String[] column1, String[] value1, String[] column2, String[] value2)                  throws IOException {              Put put = new Put(Bytes.toBytes(rowKey));// 设置rowkey              HTable table = new HTable(conf, Bytes.toBytes(tableName));// HTabel负责跟记录相关的操作如增删改查等//                                                                          // 获取表              HColumnDescriptor[] columnFamilies = table.getTableDescriptor() // 获取所有的列族                      .getColumnFamilies();                    for (int i = 0; i < columnFamilies.length; i++) {                  String familyName = columnFamilies[i].getNameAsString(); // 获取列族名                  if (familyName.equals("article")) { // article列族put数据                      for (int j = 0; j < column1.length; j++) {                          put.add(Bytes.toBytes(familyName),                                  Bytes.toBytes(column1[j]), Bytes.toBytes(value1[j]));                      }                  }                  if (familyName.equals("author")) { // author列族put数据                      for (int j = 0; j < column2.length; j++) {                          put.add(Bytes.toBytes(familyName),                                  Bytes.toBytes(column2[j]), Bytes.toBytes(value2[j]));                      }                  }              }              table.put(put);              System.out.println("add data Success!");          }                /*           * 根据rwokey查询           *            * @rowKey rowKey           *            * @tableName 表名           */          public static Result getResult(String tableName, String rowKey)                  throws IOException {              Get get = new Get(Bytes.toBytes(rowKey));              HTable table = new HTable(conf, Bytes.toBytes(tableName));// 获取表              Result result = table.get(get);              for (KeyValue kv : result.list()) {                  System.out.println("family:" + Bytes.toString(kv.getFamily()));                  System.out                          .println("qualifier:" + Bytes.toString(kv.getQualifier()));                  System.out.println("value:" + Bytes.toString(kv.getValue()));                  System.out.println("Timestamp:" + kv.getTimestamp());                  System.out.println("-------------------------------------------");              }              return result;          }                /*           * 遍历查询hbase表           *            * @tableName 表名           */          public static void getResultScann(String tableName) throws IOException {              Scan scan = new Scan();              ResultScanner rs = null;              HTable table = new HTable(conf, Bytes.toBytes(tableName));              try {                  rs = table.getScanner(scan);                  for (Result r : rs) {                      for (KeyValue kv : r.list()) {                          System.out.println("row:" + Bytes.toString(kv.getRow()));                          System.out.println("family:"                                  + Bytes.toString(kv.getFamily()));                          System.out.println("qualifier:"                                  + Bytes.toString(kv.getQualifier()));                          System.out                                  .println("value:" + Bytes.toString(kv.getValue()));                          System.out.println("timestamp:" + kv.getTimestamp());                          System.out                                  .println("-------------------------------------------");                      }                  }              } finally {                  rs.close();              }          }                /*           * 遍历查询hbase表           *            * @tableName 表名           */          public static void getResultScann(String tableName, String start_rowkey,                  String stop_rowkey) throws IOException {              Scan scan = new Scan();              scan.setStartRow(Bytes.toBytes(start_rowkey));              scan.setStopRow(Bytes.toBytes(stop_rowkey));              ResultScanner rs = null;              HTable table = new HTable(conf, Bytes.toBytes(tableName));              try {                  rs = table.getScanner(scan);                  for (Result r : rs) {                      for (KeyValue kv : r.list()) {                          System.out.println("row:" + Bytes.toString(kv.getRow()));                          System.out.println("family:"                                  + Bytes.toString(kv.getFamily()));                          System.out.println("qualifier:"                                  + Bytes.toString(kv.getQualifier()));                          System.out                                  .println("value:" + Bytes.toString(kv.getValue()));                          System.out.println("timestamp:" + kv.getTimestamp());                          System.out                                  .println("-------------------------------------------");                      }                  }              } finally {                  rs.close();              }          }                /*           * 查询表中的某一列           *            * @tableName 表名           *            * @rowKey rowKey           */          public static void getResultByColumn(String tableName, String rowKey,                  String familyName, String columnName) throws IOException {              HTable table = new HTable(conf, Bytes.toBytes(tableName));              Get get = new Get(Bytes.toBytes(rowKey));              get.addColumn(Bytes.toBytes(familyName), Bytes.toBytes(columnName)); // 获取指定列族和列修饰符对应的列              Result result = table.get(get);              for (KeyValue kv : result.list()) {                  System.out.println("family:" + Bytes.toString(kv.getFamily()));                  System.out                          .println("qualifier:" + Bytes.toString(kv.getQualifier()));                  System.out.println("value:" + Bytes.toString(kv.getValue()));                  System.out.println("Timestamp:" + kv.getTimestamp());                  System.out.println("-------------------------------------------");              }          }                /*           * 更新表中的某一列           *            * @tableName 表名           *            * @rowKey rowKey           *            * @familyName 列族名           *            * @columnName 列名           *            * @value 更新后的值           */          public static void updateTable(String tableName, String rowKey,                  String familyName, String columnName, String value)                  throws IOException {              HTable table = new HTable(conf, Bytes.toBytes(tableName));              Put put = new Put(Bytes.toBytes(rowKey));              put.add(Bytes.toBytes(familyName), Bytes.toBytes(columnName),                      Bytes.toBytes(value));              table.put(put);              System.out.println("update table Success!");          }                /*           * 查询某列数据的多个版本           *            * @tableName 表名           *            * @rowKey rowKey           *            * @familyName 列族名           *            * @columnName 列名           */          public static void getResultByVersion(String tableName, String rowKey,                  String familyName, String columnName) throws IOException {              HTable table = new HTable(conf, Bytes.toBytes(tableName));              Get get = new Get(Bytes.toBytes(rowKey));              get.addColumn(Bytes.toBytes(familyName), Bytes.toBytes(columnName));              get.setMaxVersions(5);              Result result = table.get(get);              for (KeyValue kv : result.list()) {                  System.out.println("family:" + Bytes.toString(kv.getFamily()));                  System.out                          .println("qualifier:" + Bytes.toString(kv.getQualifier()));                  System.out.println("value:" + Bytes.toString(kv.getValue()));                  System.out.println("Timestamp:" + kv.getTimestamp());                  System.out.println("-------------------------------------------");              }              /*               * List<?> results = table.get(get).list(); Iterator<?> it =               * results.iterator(); while (it.hasNext()) {               * System.out.println(it.next().toString()); }               */          }                /*           * 删除指定的列           *            * @tableName 表名           *            * @rowKey rowKey           *            * @familyName 列族名           *            * @columnName 列名           */          public static void deleteColumn(String tableName, String rowKey,                  String falilyName, String columnName) throws IOException {              HTable table = new HTable(conf, Bytes.toBytes(tableName));              Delete deleteColumn = new Delete(Bytes.toBytes(rowKey));              deleteColumn.deleteColumns(Bytes.toBytes(falilyName),                      Bytes.toBytes(columnName));              table.delete(deleteColumn);              System.out.println(falilyName + ":" + columnName + "is deleted!");          }                /*           * 删除指定的列           *            * @tableName 表名           *            * @rowKey rowKey           */          public static void deleteAllColumn(String tableName, String rowKey)                  throws IOException {              HTable table = new HTable(conf, Bytes.toBytes(tableName));              Delete deleteAll = new Delete(Bytes.toBytes(rowKey));              table.delete(deleteAll);              System.out.println("all columns are deleted!");          }                /*           * 删除表           *            * @tableName 表名           */          public static void deleteTable(String tableName) throws IOException {              HBaseAdmin admin = new HBaseAdmin(conf);              admin.disableTable(tableName);              admin.deleteTable(tableName);              System.out.println(tableName + "is deleted!");          }                public static void main(String[] args) throws Exception {                    // 创建表              String tableName = "blog2";              String[] family = { "article", "author" };              // creatTable(tableName, family);                    // 为表添加数据                    String[] column1 = { "title", "content", "tag" };              String[] value1 = {              "Head First HBase",                      "HBase is the Hadoop database. Use it when you need random, realtime read/write access to your Big Data.",                      "Hadoop,HBase,NoSQL" };              String[] column2 = { "name", "nickname" };              String[] value2 = { "nicholas", "lee" };              addData("rowkey1", "blog2", column1, value1, column2, value2);              addData("rowkey2", "blog2", column1, value1, column2, value2);              addData("rowkey3", "blog2", column1, value1, column2, value2);                    // 遍历查询              getResultScann("blog2", "rowkey4", "rowkey5");              // 根据row key范围遍历查询              getResultScann("blog2", "rowkey4", "rowkey5");              // 查询              getResult("blog2", "rowkey1");              // 查询某一列的值              getResultByColumn("blog2", "rowkey1", "author", "name");              // 更新列              updateTable("blog2", "rowkey1", "author", "name", "bin");              // 查询某一列的值              getResultByColumn("blog2", "rowkey1", "author", "name");              // 查询某列的多版本              getResultByVersion("blog2", "rowkey1", "author", "name");              // 删除一列              deleteColumn("blog2", "rowkey1", "author", "nickname");                // 删除所有列              deleteAllColumn("blog2", "rowkey1");              // 删除表              deleteTable("blog2");                }      }