PurgeOldData.java

package com.quickserverlab.quickcached.cache.impl.h2database;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
import com.quickserverlab.quickcached.QuickCached;

/**
 * H2 based implementation
 * @author Ifteqar Ahmed
 * @author Akshathkumar Shetty
 */
public class PurgeOldData {
	private static final Logger logger = Logger.getLogger(PurgeOldData.class.getName());
	
	
	private static void analyze() {
		Connection con = null;
		PreparedStatement pstmt = null;

		try {
			con = H2CacheImpl.getConnection();

			String sql = "analyze";
			pstmt = con.prepareStatement(sql);
			pstmt.executeUpdate();
		} catch (Exception e) {
			logger.log(Level.WARNING, "Error: " + e, e);
		} finally {
			try {
				pstmt.close();
			} catch (SQLException e1) {
				logger.log(Level.WARNING, "Error: " + e1, e1);
			}
			try {
				con.close();
			} catch (SQLException e1) {
				logger.log(Level.WARNING, "Error: " + e1, e1);
			}
		}
	}
	

	public static void startCleanUp() throws Exception {
		Thread analyze = new Thread("analyze") {
			public void run() {
				try {					
					Thread.sleep(1000 * 60 * 3);//3min
					analyze();
				} catch (Exception e) {
					logger.warning("Error :" + e);
				}
				
				int sleepTime = 1000 * 60 * 30;//30min
				while(true) {
					try {
						analyze();
						Thread.sleep(sleepTime);
					} catch (Exception e) {
						logger.warning("Error :" + e);
					}
				}
			}
		};
		analyze.setDaemon(true);
		analyze.start();
		
		Thread t = new Thread("PurgeOldData") {
			public void run() {
				int sleepTime = 1000 * 60;
				while(true) {
					try {
						initiateCleanig();
						Thread.sleep(sleepTime);
					} catch (Exception e) {
						logger.warning("Error :" + e);
					}
				}
			}

			private void initiateCleanig() {
				Connection con = null;
				PreparedStatement pstmt = null;

				try {
					con = H2CacheImpl.getConnection();
					java.sql.Timestamp spanOfTime = new java.sql.Timestamp(System.currentTimeMillis());

					String sql = "DELETE FROM DATA_CACHE WHERE EXPIRY_TIME_STAMP < ?";
					pstmt = con.prepareStatement(sql);
					pstmt.setTimestamp(1, spanOfTime);
					int rowsDeleted = pstmt.executeUpdate();

					if(QuickCached.DEBUG) logger.fine("Records expired: " + rowsDeleted);
				} catch (Exception e) {
					logger.log(Level.WARNING, "Error: " + e, e);
				} finally {
					try {
						pstmt.close();
					} catch (SQLException e1) {
						logger.log(Level.WARNING, "Error: " + e1, e1);
					}
					try {
						con.close();
					} catch (SQLException e1) {
						logger.log(Level.WARNING, "Error: " + e1, e1);
					}
				}
			}
		};
		t.setDaemon(true);
		t.start();
	}
}