Overview (libhdbpp-java 1.17 API)

Packages
Package	Description
org.tango.jhdb
org.tango.jhdb.data

The Hdb framework allows accessing data from Tango HDB++. Here is a small code example:

  Hdb hdb = new Hdb();

  try {

   // Connect to HDB ++ using system variables
   hdb.connect();

   // Get list of archived attributes
   String[] attList = hdb.getReader().getAttributeList();

   // Fetch data
   HdbDataSet data = hdb.getReader().getData(attList[0],"09/07/2015 12:00:00","10/07/2015 12:00:00");

   // Display data
   for(int i=0;i<data.size();i++) {
     HdbData d = data.get(i);
     long ms = d.getDataTime()/1000;
     System.out.println("  Rec #"+i+" :"+Hdb.hdbDateFormat.format(ms)+" "+d.getValueAsDouble());
   }
   
   // Close connection to HDB++
   hdb.disconnect();

  } catch (HdbFailed e) {
    System.out.println(e.getMessage());
  }

System environment variables that may need to be defined:


HDB_TYPE MYSQL,CASSANDRA,POSTGRESQL or ORACLE
HDB_NAME HDB++ Database name
HDB_USER MySQL username
HDB_PASSWORD MySQL passwrod

Cassandra specific system variables:
HDB_CONTACT_POINTS List of contact points separated by a ','

MySQL specific system variables:
HDB_MYSQL_HOST MySQL hostname
HDB_MYSQL_PORT MySQL TCP connection port

PostgreSQL specific system variables:
HDB_POSTGRESQL_HOST PostgreSQL hostname
HDB_POSTGRESQL_PORT PostgreSQL TCP connection port