Storage Engine

If you want to add your favorite storage engine to MyCassandra, you need to implement the following Storage Engine Interface.
MyCassandra already has some super classes to implement this inteface:

• DBInstance: A simple super class

• DBSchemafulInstance: A simple super class for the schemaful storage engines (MySQL, PostgreSQL, ...)

• DBSchemalessInstance: A simple super class for the schemaless storage engines (MongoDB)

• RangeDBInstance: a super class for a range query, which stores not only key but also token

  package org.apache.cassandra.db.engine;

  import java.util.Map; import java.nio.ByteBuffer;

  import org.apache.cassandra.db.DecoratedKey; import org.apache.cassandra.db.ColumnFamily;>
  /*

  • Storage Engine operations for MyCassandra.

  • MyCassandra calls Keyspace Database or Db and ColumnFamily Table after MySQL. / public interface StorageEngine { /*

    • Puts cf in a row specified by a key.
    • Includes INSERT, UPDATE and DELETE operations to a row.
    • With DELETE, cf.isMarkedForDelte() is true or cf.getRemovedColumnNames() is not null.
    • @param key a row key
    • @param cf a ColumnFamily value */ public int put(DecoratedKey key, ColumnFamily cf);

    /**

    • Gets a column family specified by a key
    • @param key a row key */ public ColumnFamily get(DecoratedKey key);

    /**

    • Range query from startWith to stopAt limit maxResults.
    • @param startWith range start key
    • @param stopAt range end key (This key is not included) */ public Map<ByteBuffer, ColumnFamily> getRangeSlice(DecoratedKey startWith, DecoratedKey stopAt, int maxResults);

    /**

    • Truncate table. */ public int truncate();

    /**

    • Drop tables. */ public int dropTable();

    /**

    • Drop database. */ public int dropDB(); }