Java tutorial
/** * Copyright (C) 2012 * by 52 North Initiative for Geospatial Open Source Software GmbH * * Contact: Andreas Wytzisk * 52 North Initiative for Geospatial Open Source Software GmbH * Martin-Luther-King-Weg 24 * 48155 Muenster, Germany * info@52north.org * * This program is free software; you can redistribute and/or modify it under * the terms of the GNU General Public License version 2 as published by the * Free Software Foundation. * * This program is distributed WITHOUT ANY WARRANTY; even without the implied * WARRANTY OF MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along with * this program (see gnu-gpl v2.txt). If not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA or * visit the Free Software Foundation web page, http://www.fsf.org. */ /** * */ package org.n52.ifgicopter.spf.input; import java.awt.Dimension; import java.awt.EventQueue; import java.awt.FlowLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.sql.Connection; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.Collection; import java.util.List; import java.util.Map; import java.util.Queue; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.LinkedBlockingQueue; import javax.swing.JButton; import javax.swing.JLabel; import javax.swing.JMenu; import javax.swing.JMenuItem; import javax.swing.JPanel; import javax.swing.JSpinner; import javax.swing.JTextField; import javax.swing.SpinnerModel; import javax.swing.SpinnerNumberModel; import javax.swing.event.ChangeEvent; import javax.swing.event.ChangeListener; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; /** * * plugin loads all data from a specified database table, the query can be filtered in the user interface. the * loaded data can be made available in a specified update interval to simulate real-time updates. * * @author Daniel Nst (d.nuest@52north.org) * */ public class HistoryPostgisInputPlugin extends PostgisInputPlugin implements Runnable { protected static Log log = LogFactory.getLog(HistoryPostgisInputPlugin.class); private static final long THREAD_SLEEP_TIME_MASTER_WHILE_LOOP = 100; private Queue<Map<String, Object>> allData = new LinkedBlockingQueue<Map<String, Object>>(); private int allDataAtStartCount = 0; private JPanel controlPanel; private int counter = 0; private boolean initialized = false; private JMenu menu; private Collection<Map<String, Object>> newData = new ArrayList<Map<String, Object>>(); private boolean running; private long sleepTimeMillis = 1000 * 2; private JButton whereButton; private JTextField whereField; /** * * @param host * @param port * @param database * @param user * @param password * @param table * @param timeColumn */ @ConstructorParameters({ "host", "port", "database", "user", "password", "table", "timeColumn" }) public HistoryPostgisInputPlugin(String host, String port, String database, String user, String password, String table, String timeColumn) { super(host, port, database, user, password, table, timeColumn); } /** * * @param host * @param port * @param database * @param user * @param password * @param table * @param timeColumn * @param where */ @ConstructorParameters({ "host", "port", "database", "user", "password", "table", "timeColumn", "where clause" }) public HistoryPostgisInputPlugin(String host, String port, String database, String user, String password, String table, String timeColumn, String where) { super(host, port, database, user, password, table, timeColumn, where); } /* * (non-Javadoc) * * @see de.ifgi.nuest.sensorVis.spf.PostgisInputPlugin#getNewData() */ @Override public List<Map<String, Object>> getNewData() { List<Map<String, Object>> currentNewData = new ArrayList<Map<String, Object>>(); currentNewData.addAll(this.newData); this.newData.clear(); appendToDataDisplay(currentNewData); return currentNewData; } /* * (non-Javadoc) * * @see de.ifgi.nuest.sensorVis.spf.PostgisInputPlugin#hasNewData() */ @Override public boolean hasNewData() { if (this.newData != null) return this.newData.size() > 0; return false; } /* * (non-Javadoc) * * @see de.ifgi.nuest.sensorVis.spf.PostgisInputPlugin#init() */ @Override public void init() throws Exception { super.init(); ExecutorService exec = Executors.newSingleThreadExecutor(); exec.submit(this); this.initialized = true; } /** * */ protected void innerRun() { if (this.allData.peek() != null) { Map<String, Object> polled = this.allData.poll(); // Date now = new Date(); // polled.put("time", Long.valueOf(now.getTime())); this.newData.add(polled); this.counter++; this.statusString = this.counter + " of " + this.allDataAtStartCount + " datasets processed."; makeStatusLabel(); } else { log.info("No more datasets!"); this.status = STATUS_NOT_RUNNING; stop(); // already sets a status, overwrite again: this.statusString = "No more data!"; makeStatusLabel(); } } /** * load all data from the table, sorted by date, ascending * * @throws SQLException */ protected void loadAllData() { this.allData.clear(); this.newData.clear(); clearDataDisplay(); this.allDataAtStartCount = 0; this.counter = 0; StringBuilder sb = new StringBuilder(); sb.append("SELECT * FROM "); sb.append(this.tableName); if (this.where != null && !this.where.isEmpty()) { if (log.isDebugEnabled()) log.debug("Filtering: " + this.where); sb.append(" WHERE "); sb.append(this.where); } sb.append(" ORDER BY "); sb.append(this.timeColumnName); List<Map<String, Object>> data = null; try { if (log.isDebugEnabled()) log.debug("Query: " + sb.toString()); Connection conn = getConnection(); if (conn == null) { log.error("Connection is null!"); this.statusString = "<html><font color='red'>Connection is null!</font></html>"; makeStatusLabel(); return; } Statement statement = conn.createStatement(); ResultSet resultSet = statement.executeQuery(sb.toString()); data = getData(resultSet); } catch (SQLException e) { log.error(e); return; } this.allData.addAll(data); this.allDataAtStartCount = this.allData.size(); this.statusString = "Loaded data (" + this.allDataAtStartCount + " rows) with query <i>" + sb.toString() + "</i>"; makeStatusLabel(); } /** * @return * */ @Override protected JPanel makeControlPanel() { if (this.controlPanel == null) { this.controlPanel = new JPanel(new FlowLayout(FlowLayout.LEADING)); JButton startButton = new JButton("Start"); startButton.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { EventQueue.invokeLater(new Runnable() { @Override public void run() { start(); } }); } }); this.controlPanel.add(startButton); JButton stopButton = new JButton("Stop"); stopButton.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { EventQueue.invokeLater(new Runnable() { @Override public void run() { stop(); } }); } }); this.controlPanel.add(stopButton); JLabel sleepTimeLabel = new JLabel("Time between points in seconds:"); this.controlPanel.add(sleepTimeLabel); double spinnerMin = 0.1d; double spinnerMax = 10000.0d; SpinnerModel model = new SpinnerNumberModel(2.0d, spinnerMin, spinnerMax, 0.1d); JSpinner sleepTimeSpinner = new JSpinner(model); sleepTimeSpinner.setToolTipText("Select time using controls or manual input within the range of " + spinnerMin + " to " + spinnerMax + "."); sleepTimeSpinner.addChangeListener(new ChangeListener() { @Override public void stateChanged(ChangeEvent e) { Object source = e.getSource(); if (source instanceof JSpinner) { final JSpinner spinner = (JSpinner) source; EventQueue.invokeLater(new Runnable() { @Override public void run() { Double value = (Double) spinner.getValue(); value = Double.valueOf(value.doubleValue() * 1000d); setSleepTimeMillis(value.longValue()); } }); } else log.warn("Unsupported ChangeEvent, need JSpinner as source: " + e); } }); // catch text change events without loosing the focus // JSpinner.DefaultEditor editor = (DefaultEditor) sleepTimeSpinner.getEditor(); // not implemented, can be done using KeyEvent, but then it hast to be checked where in the text // field the keystroke was etc. --> too complicated. this.controlPanel.add(sleepTimeSpinner); JLabel whereLabel = new JLabel("Where clause: "); this.whereField = new JTextField(this.where); this.whereField.setPreferredSize(new Dimension(200, 20)); this.whereField.setToolTipText("Insert a valid SQL 'WHERE' clause here."); this.whereButton = new JButton("Load data"); this.whereButton.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { EventQueue.invokeLater(new Runnable() { @Override public void run() { updateWhere(); loadAllData(); } }); } }); this.controlPanel.add(whereLabel); this.controlPanel.add(this.whereField); this.controlPanel.add(this.whereButton); } return this.controlPanel; } /** * @return * */ @Override protected JMenu makeMenu() { if (this.menu == null) { this.menu = new JMenu(); JMenuItem start = new JMenuItem("Start"); start.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { EventQueue.invokeLater(new Runnable() { @Override public void run() { start(); } }); } }); this.menu.add(start); JMenuItem stop = new JMenuItem("Stop"); stop.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { EventQueue.invokeLater(new Runnable() { @Override public void run() { stop(); } }); } }); this.menu.add(stop); } return this.menu; } /* * */ @Override public void run() { while (!this.initialized) { try { Thread.sleep(THREAD_SLEEP_TIME_MASTER_WHILE_LOOP); } catch (InterruptedException e) { e.printStackTrace(); } } try { while (true) { if (this.running) { innerRun(); try { Thread.sleep(this.sleepTimeMillis); } catch (InterruptedException e) { e.printStackTrace(); } } else { try { Thread.sleep(THREAD_SLEEP_TIME_MASTER_WHILE_LOOP); } catch (InterruptedException e) { e.printStackTrace(); } } } } catch (Exception e) { log.error("error in run()", e); } } /** * @param sleepTime * the sleepTime to set */ public void setSleepTimeMillis(long sleepTime) { this.sleepTimeMillis = sleepTime; } /** * */ public void start() { if (this.allData.isEmpty()) { loadAllData(); } if (this.running) return; this.running = true; this.status = STATUS_RUNNING; this.statusString = "Started!"; this.whereButton.setEnabled(false); this.whereField.setEditable(false); makeStatusLabel(); log.info("start"); } /** * */ public void stop() { if (!this.running) return; this.running = false; this.status = STATUS_NOT_RUNNING; this.statusString = "Stopped!"; this.whereButton.setEnabled(true); this.whereField.setEditable(true); makeStatusLabel(); log.info("stop"); } /** * */ protected void updateWhere() { this.where = this.whereField.getText().trim(); } }