Java tutorial
/** * The contents of this file are subject to the OpenMRS Public License * Version 1.0 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://license.openmrs.org * * Software distributed under the License is distributed on an "AS IS" * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the * License for the specific language governing rights and limitations * under the License. * * Copyright (C) OpenMRS, LLC. All Rights Reserved. */ package org.openmrs.module.usagestatistics.web.view.chart; import java.awt.BasicStroke; import java.awt.Color; import java.awt.Font; import java.util.Date; import java.util.Map; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.jfree.chart.ChartUtilities; import org.jfree.chart.JFreeChart; import org.openmrs.Location; import org.openmrs.module.usagestatistics.ActionCriteria; import org.springframework.web.bind.ServletRequestUtils; import org.springframework.web.servlet.view.AbstractView; /** * Base class for views that render usage data as a comma separated values */ public abstract class AbstractChartView extends AbstractView { protected static final Log log = LogFactory.getLog(AbstractChartView.class); private static Font font = new Font("Verdana", Font.PLAIN, 12); private static Color bkColor = new Color(240, 240, 250); private Date from, until, untilInclusive; private ActionCriteria usageFilter; private Location location; /** * @see org.springframework.web.servlet.view.AbstractView */ @Override @SuppressWarnings("unchecked") protected void renderMergedOutputModel(Map model, HttpServletRequest request, HttpServletResponse response) throws Exception { // Respond as a PNG image response.setContentType("image/png"); // Disable caching response.setHeader("Pragma", "No-cache"); response.setDateHeader("Expires", 0); response.setHeader("Cache-Control", "no-cache"); int width = ServletRequestUtils.getIntParameter(request, "width", 500); int height = ServletRequestUtils.getIntParameter(request, "height", 300); from = (Date) model.get("from"); until = (Date) model.get("until"); untilInclusive = (Date) model.get("untilInclusive"); usageFilter = (ActionCriteria) model.get("usageFilter"); location = (Location) model.get("location"); JFreeChart chart = createChart(model, request); chart.setBackgroundPaint(Color.WHITE); chart.getPlot().setOutlineStroke(new BasicStroke(0)); chart.getPlot().setOutlinePaint(getBackgroundColor()); chart.getPlot().setBackgroundPaint(getBackgroundColor()); ChartUtilities.writeChartAsPNG(response.getOutputStream(), chart, width, height); } /** * Generates a JFreeChart * @param model the model * @param request the servlet request * @return the chart object */ protected abstract JFreeChart createChart(Map<String, Object> model, HttpServletRequest request); /** * Gets the from date * @return the from date */ protected Date getFromDate() { return from; } /** * Gets the until date * @return the until date */ protected Date getUntilDate() { return until; } /** * Gets the inclusive until date (i.e. until + 1 day) * @return the until date */ protected Date getUntilInclusiveDate() { return untilInclusive; } /** * Gets the usage filter * @return the usage filter */ public ActionCriteria getUsageFilter() { return usageFilter; } /** * Gets the location * @return the location */ protected Location getLocation() { return location; } /** * Gets the font for chart rendering */ protected Font getFont() { return font; } /** * Gets the plot background color */ protected Color getBackgroundColor() { return bkColor; } }