org.jfree.chart.servlet.ServletUtilities Maven / Gradle / Ivy
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/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
* ===========================================================
*
* (C) Copyright 2000-present, by David Gilbert and Contributors.
*
* Project Info: http://www.jfree.org/jfreechart/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
* Other names may be trademarks of their respective owners.]
*
* ---------------------
* ServletUtilities.java
* ---------------------
* (C) Copyright 2002-present, by Richard Atkinson and Contributors.
*
* Original Author: Richard Atkinson;
* Contributor(s): J?rgen Hoffman;
* David Gilbert;
* Douglas Clayton;
*
*/
package org.jfree.chart.servlet;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.jfree.chart.ChartRenderingInfo;
import org.jfree.chart.ChartUtils;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.util.Args;
/**
* Utility class used for servlet related JFreeChart operations.
*/
public class ServletUtilities {
/** The filename prefix. */
private static String tempFilePrefix = "jfreechart-";
/** A prefix for "one time" charts. */
private static String tempOneTimeFilePrefix = "jfreechart-onetime-";
/**
* Returns the prefix for the temporary file names generated by this class.
*
* @return The prefix (never {@code null}).
*/
public static String getTempFilePrefix() {
return ServletUtilities.tempFilePrefix;
}
/**
* Sets the prefix for the temporary file names generated by this class.
*
* @param prefix the prefix ({@code null} not permitted).
*/
public static void setTempFilePrefix(String prefix) {
Args.nullNotPermitted(prefix, "prefix");
ServletUtilities.tempFilePrefix = prefix;
}
/**
* Returns the prefix for "one time" temporary file names generated by
* this class.
*
* @return The prefix.
*/
public static String getTempOneTimeFilePrefix() {
return ServletUtilities.tempOneTimeFilePrefix;
}
/**
* Sets the prefix for the "one time" temporary file names generated by
* this class.
*
* @param prefix the prefix ({@code null} not permitted).
*/
public static void setTempOneTimeFilePrefix(String prefix) {
Args.nullNotPermitted(prefix, "prefix");
ServletUtilities.tempOneTimeFilePrefix = prefix;
}
/**
* Saves the chart as a PNG format file in the temporary directory.
*
* @param chart the JFreeChart to be saved.
* @param width the width of the chart.
* @param height the height of the chart.
* @param session the HttpSession of the client (if {@code null}, the
* temporary file is marked as "one-time" and deleted by
* the {@link DisplayChart} servlet right after it is
* streamed to the client).
*
* @return The filename of the chart saved in the temporary directory.
*
* @throws IOException if there is a problem saving the file.
*/
public static String saveChartAsPNG(JFreeChart chart, int width, int height,
HttpSession session) throws IOException {
return ServletUtilities.saveChartAsPNG(chart, width, height, null,
session);
}
/**
* Saves the chart as a PNG format file in the temporary directory and
* populates the {@link ChartRenderingInfo} object which can be used to
* generate an HTML image map.
*
* @param chart the chart to be saved ({@code null} not permitted).
* @param width the width of the chart.
* @param height the height of the chart.
* @param info the ChartRenderingInfo object to be populated
* ({@code null} permitted).
* @param session the HttpSession of the client (if {@code null}, the
* temporary file is marked as "one-time" and deleted by
* the {@link DisplayChart} servlet right after it is
* streamed to the client).
*
* @return The filename of the chart saved in the temporary directory.
*
* @throws IOException if there is a problem saving the file.
*/
public static String saveChartAsPNG(JFreeChart chart, int width, int height,
ChartRenderingInfo info, HttpSession session) throws IOException {
Args.nullNotPermitted(chart, "chart");
ServletUtilities.createTempDir();
String prefix = ServletUtilities.tempFilePrefix;
if (session == null) {
prefix = ServletUtilities.tempOneTimeFilePrefix;
}
File tempFile = File.createTempFile(prefix, ".png",
new File(System.getProperty("java.io.tmpdir")));
ChartUtils.saveChartAsPNG(tempFile, chart, width, height, info);
if (session != null) {
ServletUtilities.registerChartForDeletion(tempFile, session);
}
return tempFile.getName();
}
/**
* Saves the chart as a JPEG format file in the temporary directory.
*
* SPECIAL NOTE: Please avoid using JPEG as an image format for charts,
* it is a "lossy" format that introduces visible distortions in the
* resulting image - use PNG instead. In addition, note that JPEG output
* is supported by JFreeChart only for JRE 1.4.2 or later.
*
* @param chart the JFreeChart to be saved.
* @param width the width of the chart.
* @param height the height of the chart.
* @param session the HttpSession of the client (if {@code null}, the
* temporary file is marked as "one-time" and deleted by
* the {@link DisplayChart} servlet right after it is
* streamed to the client).
*
* @return The filename of the chart saved in the temporary directory.
*
* @throws IOException if there is a problem saving the file.
*/
public static String saveChartAsJPEG(JFreeChart chart, int width,
int height, HttpSession session)
throws IOException {
return ServletUtilities.saveChartAsJPEG(chart, width, height, null,
session);
}
/**
* Saves the chart as a JPEG format file in the temporary directory and
* populates the {@code ChartRenderingInfo} object which can be used
* to generate an HTML image map.
*
* SPECIAL NOTE: Please avoid using JPEG as an image format for charts,
* it is a "lossy" format that introduces visible distortions in the
* resulting image - use PNG instead. In addition, note that JPEG output
* is supported by JFreeChart only for JRE 1.4.2 or later.
*
* @param chart the chart to be saved ({@code null} not permitted).
* @param width the width of the chart
* @param height the height of the chart
* @param info the ChartRenderingInfo object to be populated
* @param session the HttpSession of the client (if {@code null}, the
* temporary file is marked as "one-time" and deleted by
* the {@link DisplayChart} servlet right after it is
* streamed to the client).
*
* @return The filename of the chart saved in the temporary directory
*
* @throws IOException if there is a problem saving the file.
*/
public static String saveChartAsJPEG(JFreeChart chart, int width,
int height, ChartRenderingInfo info, HttpSession session)
throws IOException {
Args.nullNotPermitted(chart, "chart");
ServletUtilities.createTempDir();
String prefix = ServletUtilities.tempFilePrefix;
if (session == null) {
prefix = ServletUtilities.tempOneTimeFilePrefix;
}
File tempFile = File.createTempFile(prefix, ".jpeg",
new File(System.getProperty("java.io.tmpdir")));
ChartUtils.saveChartAsJPEG(tempFile, chart, width, height, info);
if (session != null) {
ServletUtilities.registerChartForDeletion(tempFile, session);
}
return tempFile.getName();
}
/**
* Creates the temporary directory if it does not exist. Throws a
* {@code RuntimeException} if the temporary directory is
* {@code null}. Uses the system property {@code java.io.tmpdir}
* as the temporary directory. This sounds like a strange thing to do but
* my temporary directory was not created on my default Tomcat 4.0.3
* installation. Could save some questions on the forum if it is created
* when not present.
*/
protected static void createTempDir() {
String tempDirName = System.getProperty("java.io.tmpdir");
if (tempDirName == null) {
throw new RuntimeException("Temporary directory system property "
+ "(java.io.tmpdir) is null.");
}
// create the temporary directory if it doesn't exist
File tempDir = new File(tempDirName);
if (!tempDir.exists()) {
tempDir.mkdirs();
}
}
/**
* Adds a {@link ChartDeleter} object to the session object with the name
* {@code JFreeChart_Deleter} if there is not already one bound to the
* session and adds the filename to the list of charts to be deleted.
*
* @param tempFile the file to be deleted.
* @param session the HTTP session of the client.
*/
protected static void registerChartForDeletion(File tempFile,
HttpSession session) {
// Add chart to deletion list in session
if (session != null) {
ChartDeleter chartDeleter
= (ChartDeleter) session.getAttribute("JFreeChart_Deleter");
if (chartDeleter == null) {
chartDeleter = new ChartDeleter();
session.setAttribute("JFreeChart_Deleter", chartDeleter);
}
chartDeleter.addChart(tempFile.getName());
}
else {
System.out.println("Session is null - chart will not be deleted");
}
}
/**
* Binary streams the specified file in the temporary directory to the
* HTTP response in 1KB chunks.
*
* @param filename the name of the file in the temporary directory.
* @param response the HTTP response object.
*
* @throws IOException if there is an I/O problem.
*/
public static void sendTempFile(String filename,
HttpServletResponse response) throws IOException {
File file = new File(System.getProperty("java.io.tmpdir"), filename);
ServletUtilities.sendTempFile(file, response);
}
/**
* Binary streams the specified file to the HTTP response in 1KB chunks.
*
* @param file the file to be streamed.
* @param response the HTTP response object.
*
* @throws IOException if there is an I/O problem.
*/
public static void sendTempFile(File file, HttpServletResponse response)
throws IOException {
String mimeType = null;
String filename = file.getName();
if (filename.length() > 5) {
if (filename.substring(filename.length() - 5,
filename.length()).equals(".jpeg")) {
mimeType = "image/jpeg";
}
else if (filename.substring(filename.length() - 4,
filename.length()).equals(".png")) {
mimeType = "image/png";
}
}
ServletUtilities.sendTempFile(file, response, mimeType);
}
/**
* Binary streams the specified file to the HTTP response in 1KB chunks.
*
* @param file the file to be streamed.
* @param response the HTTP response object.
* @param mimeType the mime type of the file, null allowed.
*
* @throws IOException if there is an I/O problem.
*/
public static void sendTempFile(File file, HttpServletResponse response,
String mimeType) throws IOException {
if (file.exists()) {
BufferedInputStream bis = new BufferedInputStream(
new FileInputStream(file));
// Set HTTP headers
if (mimeType != null) {
response.setHeader("Content-Type", mimeType);
}
response.setHeader("Content-Length", String.valueOf(file.length()));
SimpleDateFormat sdf = new SimpleDateFormat(
"EEE, dd MMM yyyy HH:mm:ss z", Locale.ENGLISH);
sdf.setTimeZone(TimeZone.getTimeZone("GMT"));
response.setHeader("Last-Modified",
sdf.format(new Date(file.lastModified())));
BufferedOutputStream bos = new BufferedOutputStream(
response.getOutputStream());
byte[] input = new byte[1024];
boolean eof = false;
while (!eof) {
int length = bis.read(input);
if (length == -1) {
eof = true;
}
else {
bos.write(input, 0, length);
}
}
bos.flush();
bis.close();
bos.close();
}
else {
throw new FileNotFoundException(file.getAbsolutePath());
}
}
/**
* Perform a search/replace operation on a String
* There are String methods to do this since (JDK 1.4)
*
* @param inputString the String to have the search/replace operation.
* @param searchString the search String.
* @param replaceString the replace String.
*
* @return The String with the replacements made.
*/
public static String searchReplace(String inputString,
String searchString,
String replaceString) {
int i = inputString.indexOf(searchString);
if (i == -1) {
return inputString;
}
String r = "";
r += inputString.substring(0, i) + replaceString;
if (i + searchString.length() < inputString.length()) {
r += searchReplace(inputString.substring(i + searchString.length()),
searchString, replaceString);
}
return r;
}
}