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/*
* Copyright 2013 Jesse Morgan
*/
package com.p4square.grow.backend.db;
import com.netflix.astyanax.AstyanaxContext;
import com.netflix.astyanax.connectionpool.exceptions.ConnectionException;
import com.netflix.astyanax.connectionpool.impl.ConnectionPoolConfigurationImpl;
import com.netflix.astyanax.connectionpool.impl.CountingConnectionPoolMonitor;
import com.netflix.astyanax.connectionpool.NodeDiscoveryType;
import com.netflix.astyanax.connectionpool.OperationResult;
import com.netflix.astyanax.impl.AstyanaxConfigurationImpl;
import com.netflix.astyanax.Keyspace;
import com.netflix.astyanax.ColumnMutation;
import com.netflix.astyanax.model.Column;
import com.netflix.astyanax.model.ColumnFamily;
import com.netflix.astyanax.model.ColumnList;
import com.netflix.astyanax.MutationBatch;
import com.netflix.astyanax.serializers.StringSerializer;
import com.netflix.astyanax.thrift.ThriftFamilyFactory;
import org.apache.log4j.Logger;
/**
* Cassandra Database Abstraction for the Backend.
*
* @author Jesse Morgan <jesse@jesterpm.net>
*/
public class CassandraDatabase {
private static Logger cLog = Logger.getLogger(CassandraDatabase.class);
// Configuration fields.
private String mClusterName;
private String mKeyspaceName;
private String mSeedEndpoint = "127.0.0.1:9160";
private int mPort = 9160;
private AstyanaxContext<Keyspace> mContext;
private Keyspace mKeyspace;
/**
* Connect to Cassandra.
*
* Cluster and Keyspace must be set before calling init().
*/
public void init() {
mContext = new AstyanaxContext.Builder()
.forCluster(mClusterName)
.forKeyspace(mKeyspaceName)
.withAstyanaxConfiguration(new AstyanaxConfigurationImpl()
.setDiscoveryType(NodeDiscoveryType.RING_DESCRIBE)
)
.withConnectionPoolConfiguration(new ConnectionPoolConfigurationImpl("MyConnectionPool")
.setPort(mPort)
.setMaxConnsPerHost(1)
.setSeeds(mSeedEndpoint)
)
.withConnectionPoolMonitor(new CountingConnectionPoolMonitor())
.buildKeyspace(ThriftFamilyFactory.getInstance());
mContext.start();
mKeyspace = mContext.getClient();
}
/**
* Close the database connection.
*/
public void close() {
mContext.shutdown();
}
/**
* Set the cluster name to connect to.
*/
public void setClusterName(final String cluster) {
mClusterName = cluster;
}
/**
* Set the name of the keyspace to open.
*/
public void setKeyspaceName(final String keyspace) {
mKeyspaceName = keyspace;
}
/**
* Change the seed endpoint.
* The default is 127.0.0.1:9160.
*/
public void setSeedEndpoint(final String endpoint) {
mSeedEndpoint = endpoint;
}
/**
* Change the port to connect to.
* The default is 9160.
*/
public void setPort(final int port) {
mPort = port;
}
/**
* @return The entire row associated with this key.
*/
public ColumnList<String> getRow(final String cfName, final String key) {
try {
ColumnFamily<String, String> cf = new ColumnFamily(cfName,
StringSerializer.get(),
StringSerializer.get());
OperationResult<ColumnList<String>> result =
mKeyspace.prepareQuery(cf)
.getKey(key)
.execute();
return result.getResult();
} catch (ConnectionException e) {
cLog.error("getRow failed due to Connection Exception", e);
throw new RuntimeException(e);
}
}
/**
* @return The value associated with the given key.
*/
public String getKey(final String cfName, final String key) {
return getKey(cfName, key, "value");
}
/**
* @return The value associated with the given key, column pair.
*/
public String getKey(final String cfName, final String key, final String column) {
final ColumnList<String> row = getRow(cfName, key);
if (row != null) {
final Column rowColumn = row.getColumnByName(column);
if (rowColumn != null) {
return rowColumn.getStringValue();
}
}
return null;
}
/**
* Assign value to key.
*/
public void putKey(final String cfName, final String key, final String value) {
putKey(cfName, key, "value", value);
}
/**
* Assign value to the key, column pair.
*/
public void putKey(final String cfName, final String key,
final String column, final String value) {
ColumnFamily<String, String> cf = new ColumnFamily(cfName,
StringSerializer.get(),
StringSerializer.get());
MutationBatch m = mKeyspace.prepareMutationBatch();
m.withRow(cf, key).putColumn(column, value);
try {
m.execute();
} catch (ConnectionException e) {
cLog.error("putKey failed due to Connection Exception", e);
throw new RuntimeException(e);
}
}
/**
* Remove a key, column pair.
*/
public void deleteKey(final String cfName, final String key, final String column) {
ColumnFamily<String, String> cf = new ColumnFamily(cfName,
StringSerializer.get(),
StringSerializer.get());
try {
ColumnMutation m = mKeyspace.prepareColumnMutation(cf, key, column);
m.deleteColumn().execute();
} catch (ConnectionException e) {
cLog.error("deleteKey failed due to Connection Exception", e);
throw new RuntimeException(e);
}
}
}
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