org.qbroker.net

Class CQLConnector

java.lang.Object

org.qbroker.net.CQLConnector

All Implemented Interfaces:

Connector

public class CQLConnector
extends java.lang.Object
implements Connector

CQLConnector connects to a Cassandra cluster and provides some basic CQL operation methods: select(), and execute().

This is NOT MT-Safe. Therefore, you need to use multiple instances to achieve your MT-Safty goal.

Author:

yannanlu@yahoo.com

Field Summary

Fields

Modifier and Type	Field and Description
static int	ACTION_COUNT
static int	ACTION_DELETE
static int	ACTION_LIST
static int	ACTION_SELECT
static int	ACTION_UPDATE
static java.lang.String	FS
protected java.lang.String	hostname
protected boolean	isConnected
protected java.lang.String	keyspace
protected java.lang.String	password
protected int	port
static java.lang.String	RS
protected com.datastax.driver.core.Session	session
protected int	timeout
protected java.lang.String	uri
protected java.lang.String	username

Constructor Summary

Constructors

Constructor and Description
CQLConnector(java.util.Map props) Creates new CQLConnector

Method Summary

Modifier and Type	Method and Description
void	close() closes and shutdown the Cassandra cluster
static java.lang.String	doSearchReplace(java.lang.String s, java.lang.String r, java.lang.String text)
static java.lang.String	escapeJSON(java.lang.String text)
static java.lang.String	escapeXML(java.lang.String text)
static java.lang.StringBuffer	getResult(int type, com.datastax.driver.core.ResultSet rset, int[] rc) It gets all the rows from the ReseulSet and packs them into a StringBuffer according to the ResultType.
static java.lang.StringBuffer	getResult(java.util.List<com.datastax.driver.core.ColumnMetadata> list, int[] rc) It gets all the rows from the list of ColumnMetadata and packs them into a StringBuffer according to the ResultType.
java.lang.String	getURI()
boolean	isConnected()
java.lang.StringBuffer	list(java.lang.String table, int[] rc) returns a string buffer with info on all columns for a specific table
static void	main(java.lang.String[] args) tests Cassandra basic operations
java.lang.String	reconnect() It reconnects and returns null or error message upon failure
java.lang.StringBuffer	select(int rt, java.lang.String cqlStr, int[] rc) returns selected results in string buffer for the query
java.lang.String	update(java.lang.String cqlStr) returns null for success or error msg for failure otherwise

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

hostname

protected java.lang.String hostname

keyspace

protected java.lang.String keyspace

username

protected java.lang.String username

password

protected java.lang.String password

uri

protected java.lang.String uri

port

protected int port

timeout

protected int timeout

isConnected

protected boolean isConnected

ACTION_LIST

public static final int ACTION_LIST

See Also:

Constant Field Values

ACTION_COUNT

public static final int ACTION_COUNT

See Also:

Constant Field Values

ACTION_SELECT

public static final int ACTION_SELECT

See Also:

Constant Field Values

ACTION_UPDATE

public static final int ACTION_UPDATE

See Also:

Constant Field Values

ACTION_DELETE

public static final int ACTION_DELETE

See Also:

Constant Field Values

FS

public static final java.lang.String FS

See Also:

Constant Field Values

RS

public static final java.lang.String RS

See Also:

Constant Field Values

session

protected com.datastax.driver.core.Session session

Constructor Detail

CQLConnector

public CQLConnector(java.util.Map props)

Creates new CQLConnector

Method Detail

getURI

public java.lang.String getURI()

Specified by:

getURI in interface Connector

isConnected

public boolean isConnected()

Specified by:

isConnected in interface Connector

reconnect

public java.lang.String reconnect()

It reconnects and returns null or error message upon failure

Specified by:

reconnect in interface Connector

list

public java.lang.StringBuffer list(java.lang.String table,
                                   int[] rc)
                            throws com.datastax.driver.core.exceptions.DriverException

returns a string buffer with info on all columns for a specific table

Throws:

com.datastax.driver.core.exceptions.DriverException

select

public java.lang.StringBuffer select(int rt,
                                     java.lang.String cqlStr,
                                     int[] rc)
                              throws com.datastax.driver.core.exceptions.DriverException

returns selected results in string buffer for the query

Throws:

com.datastax.driver.core.exceptions.DriverException

update

public java.lang.String update(java.lang.String cqlStr)

returns null for success or error msg for failure otherwise

close

public void close()

closes and shutdown the Cassandra cluster

Specified by:

close in interface Connector

getResult

public static java.lang.StringBuffer getResult(int type,
                                               com.datastax.driver.core.ResultSet rset,
                                               int[] rc)
                                        throws com.datastax.driver.core.exceptions.DriverException

It gets all the rows from the ReseulSet and packs them into a StringBuffer according to the ResultType. The int array of rc should have at least two numbers. The first is for the number of rows. The second is for the number of columns.
If any returned string is null, it will be reset into an empty string.

Throws:

com.datastax.driver.core.exceptions.DriverException

getResult

public static java.lang.StringBuffer getResult(java.util.List<com.datastax.driver.core.ColumnMetadata> list,
                                               int[] rc)
                                        throws com.datastax.driver.core.exceptions.DriverException

It gets all the rows from the list of ColumnMetadata and packs them into a StringBuffer according to the ResultType. The int array of rc should have at least two numbers. The first is for the number of rows. The second is for the number of columns.
If any returned string is null, it will be reset into an empty string.

Throws:

com.datastax.driver.core.exceptions.DriverException

escapeJSON

public static java.lang.String escapeJSON(java.lang.String text)

escapeXML

public static java.lang.String escapeXML(java.lang.String text)

doSearchReplace

public static java.lang.String doSearchReplace(java.lang.String s,
                                               java.lang.String r,
                                               java.lang.String text)

main

public static void main(java.lang.String[] args)

tests Cassandra basic operations