Changes between Initial Version and Version 1 of NCHCCloudCourse100929_4_HBExp

Timestamp:

Sep 27, 2010, 6:24:03 PM (15 years ago)

Author:

waue

Comment:

--

NCHCCloudCourse100929_4_HBExp

@@ +1 @@
+{{{
+#!html
+<div style="text-align: center; color:#151B8D"><big style="font-weight: bold;"><big><big>
+HBase 進階課程 
+</big></big></big></div> <div style="text-align: center; color:#7E2217"><big style="font-weight: bold;"><big>
+程式範例練習
+</big></big></div>
+}}}
+
+[wiki:NCHCCloudCourse100928 回課程大綱 << ] 第一關 [wiki:NCHCCloudCourse100929_4_HBEX2 > 下一關 ] 
+
+= 範例一：新增Table =
+
+ * 看懂以下程式碼，並成功執行它
+
+{{{
+package org.nchc.hbase;
+
+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.client.HBaseAdmin;
+import org.apache.hadoop.util.GenericOptionsParser;
+
+public class CreateTable {
+        public static void createHBaseTable(String tablename, String family)
+                        throws IOException {
+                // HTableDescriptor contains the name of an HTable, and its column
+                // families
+                // HTableDescriptor 用來描述table的屬性
+                HTableDescriptor htd = new HTableDescriptor(tablename);
+                // HColumnDescriptor HColumnDescriptor contains information about a
+                // column family such as the number of versions, compression settings,
+                // etc.
+                // HTableDescriptor 透過 add() 方法來加入Column family
+
+                htd.addFamily(new HColumnDescriptor(family));
+
+                // HBaseConfiguration 能接收 hbase-site.xml 的設定值
+                HBaseConfiguration config = new HBaseConfiguration();
+                // 檔案的操作則使用 HBaseAdmin
+                HBaseAdmin admin = new HBaseAdmin(config);
+                // 檢查
+                if (admin.tableExists(tablename)) {
+                        System.out.println("Table: " + tablename + "Existed.");
+                } else {
+                        System.out.println("create new table: " + tablename);
+                        // 建立
+                        admin.createTable(htd);
+                }
+        }
+
+        static public void main(String argv[]) throws IOException {
+                
+                String[] otherArgs = new GenericOptionsParser(new Configuration(), argv)
+                                .getRemainingArgs();
+                if (otherArgs.length < 2) {
+                        System.out.println("CreateTable <newTableName> <Family>");
+                        return;
+                }
+                
+                String tablename = otherArgs[0];
+                String family = otherArgs[1];
+
+                System.out.println("1. create table :" + tablename);
+
+                createHBaseTable(tablename, family);
+        }
+}
+
+}}}
+