view flys-artifacts/src/main/java/de/intevation/flys/artifacts/datacage/templating/ResultData.java @ 5779:ebec12def170

Datacage: Add a pool of builders to make it multi threadable. XML DOM is not thread safe. Therefore the old implementation only allowed one thread to use the builder at a time. As the complexity of the configuration has increased over time this has become a bottleneck of the whole application because it took quiet some time to build a result. Furthermore the builder code path is visited very frequent. So many concurrent requests were piled up resulting in long waits for the users. To mitigate this problem a round robin pool of builders is used now. Each of the pooled builders has an independent copy of the XML template and can be run in parallel. The number of builders is determined by the system property 'flys.datacage.pool.size'. It defaults to 4.
author Sascha L. Teichmann <teichmann@intevation.de>
date Sun, 21 Apr 2013 12:48:09 +0200
parents ac2746f3e75f
children
line wrap: on
line source
package de.intevation.flys.artifacts.datacage.templating;

import java.io.Serializable;

import java.sql.ResultSetMetaData;
import java.sql.ResultSet;
import java.sql.SQLException;

import java.util.List;
import java.util.ArrayList;

import org.apache.log4j.Logger;


/** Result Data from a DB/SQL query. */
public class ResultData
implements   Serializable
{
    private static Logger log = Logger.getLogger(ResultData.class);

    protected String [] columns;

    protected List<Object []> rows;

    public ResultData() {
        rows = new ArrayList<Object []>();
    }

    public ResultData(String [] columns, List<Object []> rows) {
        this.columns = columns;
        this.rows = rows;
    }

    public ResultData(ResultSetMetaData meta)
    throws SQLException
    {
        this();

        boolean debug = log.isDebugEnabled();

        int N = meta.getColumnCount();

        columns = new String[N];

        if (debug) {
            log.debug("ResultSet column names:");
        }

        for (int i = 1; i <= N; ++i) {
            columns[i-1] = meta.getColumnLabel(i).toUpperCase();
            if (debug) {
                log.debug("    " + i + ": " + columns[i-1]);
            }
        }
    }

    public String [] getColumnLabels() {
        return columns;
    }

    public ResultData addAll(ResultSet result) throws SQLException {
        while (result.next()) {
            add(result);
        }
        return this;
    }

    public void add(ResultSet result) throws SQLException {
        Object [] row = new Object[columns.length];
        for (int i = 0; i < columns.length; ++i) {
            row[i] = result.getObject(i+1);
        }
        rows.add(row);
    }

    public List<Object []> getRows() {
        return rows;
    }

    public boolean isEmpty() {
        return rows.isEmpty();
    }
}
// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :

http://dive4elements.wald.intevation.org