H base programming

  • 452 views
Uploaded on

HBase tutorial to get started

HBase tutorial to get started

More in: Technology
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Be the first to comment
No Downloads

Views

Total Views
452
On Slideshare
0
From Embeds
0
Number of Embeds
2

Actions

Shares
Downloads
34
Comments
0
Likes
2

Embeds 0

No embeds

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
    No notes for slide

Transcript

  • 1. HBase Programming Mani mmaniga@yahoo.co.uk
  • 2. CreateTablepublic static int VERSION = 5;public static void createTable(byte[] tableName, byte[][] families, int numVersions) throws IOException {HBaseConfiguration hbaseConfig = new HBaseConfiguration();HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig);HTableDescriptor htableDesc = new HTableDescriptor(tableName); for (byte[] family : families) { HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(family, numVersions, HColumnDescriptor.DEFAULT_COMPRESSION, HColumnDescriptor.DEFAULT_IN_MEMORY, HColumnDescriptor.DEFAULT_BLOCKCACHE, HColumnDescriptor.DEFAULT_TTL, HColumnDescriptor.DEFAULT_BLOOMFILTER); htableDesc.addFamily(hColumnDescriptor); } hbaseAdmin.createTable(htableDesc); }
  • 3. Table Exists & Get Table Namepublic static boolean tableExist(byte[] tableName) throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); return hbaseAdmin.tableExists(tableName); }public static List<String> getTableNames() throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); List<String> tables = new ArrayList<String>(); for (HTableDescriptor htableDesc : hbaseAdmin.listTables()) { printTableDescriptors(htableDesc); tables.add(htableDesc.getNameAsString()); } return tables; }public static void printTableDescriptors(HTableDescriptor descriptor) { System.out.println("Table name " + descriptor.getNameAsString()); for (HColumnDescriptor columnDescriptor : descriptor.getColumnFamilies()) { System.out.println(columnDescriptor.getNameAsString()); System.out.println(columnDescriptor.getMaxVersions()); System.out.println(columnDescriptor.getMinVersions()); } }
  • 4. Insert Recordpublic static void insertRecord(HTable htable, byte[] columnFamily, boolean createColumnFamily, HashMap<String, HashMap<String, String>> creditLogMaps) throws IOException { String rowKey;// record key HashMap<String, String> columnData; if (!columnFamilyExist(htable, columnFamily)) { if (!createColumnFamily) return; else createColumnFamily(htable, columnFamily, VERSION); } for (Map.Entry<String, HashMap<String, String>> creditLogMap :creditLogMaps.entrySet()) { rowKey = creditLogMap.getKey(); columnData = creditLogMap.getValue(); Put put = new Put(rowKey.getBytes()); for (Map.Entry<String, String> kv : columnData.entrySet()) { put.add(columnFamily, kv.getKey().getBytes(), kv.getValue() .getBytes()); } htable.put(put); System.out.println("Record inserted"); } }
  • 5. Create Column Familypublic static void createColumnFamily(HTable htable, byte[] columnFamily, int numVersions) throws IOException { disableTable(htable.getTableName()); while (isTableEnabled(htable.getTableName()));// wait untill table isdisabled HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); HColumnDescriptor hColumnDescriptor = new HColumnDescriptor( columnFamily, numVersions, HColumnDescriptor.DEFAULT_COMPRESSION, HColumnDescriptor.DEFAULT_IN_MEMORY, HColumnDescriptor.DEFAULT_BLOCKCACHE, HColumnDescriptor.DEFAULT_TTL, HColumnDescriptor.DEFAULT_BLOOMFILTER); hbaseAdmin.addColumn(htable.getTableName(), hColumnDescriptor); enableTable(htable.getTableName()); }
  • 6. Get Column Familypublic static List<String> getColumnFamilies(HTable htable) throws IOException { List<String> columnFamilies = new ArrayList<String>(); for (HColumnDescriptor columnDesc :htable.getTableDescriptor().getColumnFamilies()) { columnFamilies.add(columnDesc.getNameAsString()); } return columnFamilies; }public static boolean columnFamilyExist(HTable htable, byte[] columnFamily)throws IOException { boolean hasColumn = false; if (htable.getTableDescriptor().getFamily(columnFamily) != null) { hasColumn = true; } return hasColumn; }public static boolean isTableEnabled(byte[] tableName) throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); System.out.println("Table enabled " + hbaseAdmin.isTableEnabled(tableName)); return hbaseAdmin.isTableEnabled(tableName); }
  • 7. Enable, Disable & Drop Tablepublic static void enableTable(byte[] tableName) throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); hbaseAdmin.enableTable(tableName); } public static void disableTable(byte[] tableName) throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); hbaseAdmin.disableTable(tableName); System.out.println("Table " + new String(tableName) + " disabled"); } public static void dropTable(byte[] tableName) throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); hbaseAdmin.deleteTable(tableName); System.out.println("Table " + new String(tableName) + " deleted"); }
  • 8. Get Table, Get & Delete Recordpublic static HTable getTable(byte[] tableName) throws IOException { HBaseConfiguration hbaseConfig = new HBaseConfiguration(); HBaseAdmin hbaseAdmin = new HBaseAdmin(hbaseConfig); return new HTable(hbaseConfig, tableName);}public static void deleteRecord(HTable hTable, String rowKey) throws IOException { Delete delete = new Delete(rowKey.getBytes()); hTable.delete(delete); System.out.println("Record " + rowKey + " deleted ");}public static PResultSet getRecord(HTable hTable, String rowKey, String family) throws IOException { Get get = new Get(rowKey.getBytes()); get.addFamily(family.getBytes()); PResultSet resultSet = new PResultSet(hTable, get); return resultSet;}
  • 9. Scan Records• public static void scanRecords(byte[] startKey, HTable hTable)• throws IOException {• Scan scan = new Scan(startKey);• ResultScanner resultScanner = hTable.getScanner(scan);• System.out.println("#########Scan result ################");• for (Result result : resultScanner) {• System.out.println(">key is " + new String(result.getRow()));• for (KeyValue kv : result.raw()) {• System.out.println(new String(kv.getFamily()) + ":"• + new String(kv.getQualifier()) + " = "• + new String(kv.getValue()));• }• }• System.out.println("--------Scan result ends here-------------------");• }
  • 10. Scan Records by Filterpublic static void scanRecords(byte[] startKey, HTable hTable, TestFilter testFilter)throws IOException { Scan scan = new Scan(startKey); scan.setFilter(testFilter.getFilters()); ResultScanner resultScanner = hTable.getScanner(scan); System.out.println("#########filter scan result ################"); for (Result result : resultScanner) { System.out.println(">key is " + new String(result.getRow())); for (KeyValue kv : result.raw()) { System.out.println(new String(kv.getFamily()) + ":" + new String(kv.getQualifier()) + " = " + new String(kv.getValue())); } } System.out.println("--------Scan result ends here-------------------"); }
  • 11. Filter Objectclass FilterObject { String columnFamilyName; String columnName; String value; CompareOp compareOp; public FilterObject(String columnFamilyName, String columnName, String value, CompareOp compareOp) { this.columnFamilyName = columnFamilyName; this.columnName = columnName; this.value = value; this.compareOp = compareOp; }}
  • 12. Filter Classclass TestFilter { private List<FilterObject> filterObjects; private FilterList filterList; public TestFilter() { filterObjects = new ArrayList<FilterObject>(); filterList = new FilterList(); } public void addFilterObject(FilterObject ft) { filterObjects.add(ft); } public FilterList getFilters() { for (FilterObject filterObject : filterObjects) { filterList.addFilter(new SingleColumnValueFilter( filterObject.columnFamilyName.getBytes(), filterObject.columnName.getBytes(), filterObject.compareOp, filterObject.value.getBytes())); } return filterList; }}
  • 13. ResultSetclass PResultSet { private String tableName; private String columnFamily; private HashMap<String, String> resutlMap; private Result rs; public PResultSet(HTable hTable, Get get) throws IOException { this.rs = hTable.get(get); this.tableName = hTable.getTableDescriptor().getNameAsString(); this.columnFamily = hTable.getTableDescriptor().getColumnFamilies() .toString(); this.resutlMap = new HashMap<String, String>(); } public String getTableName() { return tableName; } public void setTableName(String tableName) { this.tableName = tableName; }Cont…
  • 14. ResultSet cont….public String getColumnFamily() { return columnFamily; } public void setColumnFamily(String columnFamily) { this.columnFamily = columnFamily; } public HashMap<String, String> getResutlMap() { return resutlMap; } public void setResutlMap(HashMap<String, String> resutlMap) { this.resutlMap = resutlMap; } public String toString() { System.out.println("TableName :" + getTableName()); System.out.println("ColumnFamily : " + getColumnFamily()); System.out.println("No Of Rows : " + rs.size()); for (KeyValue kv : rs.raw()) { resutlMap.put(Bytes.toString(kv.getQualifier()), Bytes.toString(kv.getValue())); } return resutlMap.toString(); }}
  • 15. Testing Code – Create FunctionsCreate Table Testing: String tableName = "TrainingDB"; String familyName = "CreditLog"; byte[] tableNameBytes = tableName.getBytes(); byte[] familyBytes = familyName.getBytes(); byte[][] columnFamilyByteArray = new byte[][] { familyBytes }; if (tableExist(tableNameBytes)) { System.out.println("Table exist"); disableTable(tableNameBytes); dropTable(tableNameBytes); } createTable(tableNameBytes, columnFamilyByteArray, 5); HTable hTable = getTable(tableNameBytes); System.out.println("Successfully created"); System.out.println("Column exist : " + columnFamilyExist(hTable, familyBytes));
  • 16. Testing Code – PutHashMap<String, HashMap<String, String>> creditLogMaps = new HashMap<String, HashMap<String, String>>(); HashMap<String, String> creditLogMap = new HashMap<String, String>(); creditLogMap.put("Name", "Karthik"); creditLogMap.put("Age", "36"); creditLogMap.put("Rating", "Good"); creditLogMap.put("Limit", "404$"); String rowKey = "1753-4343-4322-5423"; creditLogMaps.put(rowKey, creditLogMap); creditLogMap = new HashMap<String, String>(); creditLogMap.put("Name", "Manik"); creditLogMap.put("Age", "36"); creditLogMap.put("Rating", "Average"); creditLogMap.put("Limit", "-2$"); String rowKey2 = "5557-4343-4322-5422"; creditLogMaps.put(rowKey2, creditLogMap); insertRecord(hTable, familyBytes, false, creditLogMaps);
  • 17. Testing Code - PutHashMap<String, String> transLogMap = new HashMap<String, String>(); transLogMap.put("Date", "23-NOV-2011"); transLogMap.put("Amount", "$30"); transLogMap.put("Balance", "$450"); transLogMap.put("Bank", "Barclays"); HashMap<String, HashMap<String, String>> transLogMaps = new HashMap<String, HashMap<String, String>>(); transLogMaps.put(rowKey, transLogMap); insertRecord(hTable, "TransLog".getBytes(), true, transLogMaps);
  • 18. Testing Code – List TablesSystem.out.println("Tables in HBase"); for (String name : getTableNames()) { System.out.println("# " + name); System.out.println("Table columns"); HTable table = getTable(name.getBytes()); for (String columnName : getColumnFamilies(table)) { System.out.println("- " + columnName); } }
  • 19. Testing Code – Get & Scan Records System.out.println(getRecord(hTable, rowKey, familyName).toString()); System.out.println(getRecord(hTable, rowKey, "TransLog").toString()); scanRecords(rowKey.getBytes(), hTable); FilterObject filterObject = new FilterObject(familyName, "Age", "36", CompareOp.EQUAL); FilterObject filterObject2 = new FilterObject(familyName, "Limit", "-2$", CompareOp.EQUAL); TestFilter testFilter = new TestFilter(); testFilter.addFilterObject(filterObject); testFilter.addFilterObject(filterObject2); scanRecords(rowKey.getBytes(), hTable, testFilter); deleteRecord(hTable, rowKey); System.out.println("After delete"); scanRecords(rowKey.getBytes(), hTable);
  • 20. Happy Coding– Mani– mmaniga@yahoo.co.uk