小編給大家分享一下如何通過JFreeChart實現在jsp頁面畫甘特圖，希望大家閱讀完這篇文章之后都有所收獲，下面讓我們一起去探討吧！

讓客戶滿意是我們工作的目標，不斷超越客戶的期望值來自于我們對這個行業(yè)的熱愛。我們立志把好的技術通過有效、簡單的方式提供給客戶，將通過不懈努力成為客戶在信息化領域值得信任、有價值的長期合作伙伴，公司提供的服務項目有：域名與空間、網絡空間、營銷軟件、網站建設、永年網站維護、網站推廣。

首先把重要的代碼粘出來供大家參考，項目源碼和數據庫信息表，以及參考的資料和一些資料的網址我就打包放在下面，大家可以下載后學習參考。

ProgressControl.java//完成從數據庫讀數據，生成甘特圖。

package com.angrybirds.DAO;   import java.io.IOException;  import java.io.PrintWriter;  //import java.util.Date;  import java.sql.*;  import java.util.ArrayList;  import java.util.ListIterator;   import javax.servlet.http.HttpSession;   import org.jfree.chart.ChartFactory;  import org.jfree.chart.ChartRenderingInfo;  import org.jfree.chart.ChartUtilities;  import org.jfree.chart.JFreeChart;  import org.jfree.chart.entity.StandardEntityCollection;  import org.jfree.chart.servlet.ServletUtilities;  import org.jfree.data.gantt.Task;  import org.jfree.data.gantt.TaskSeries;  import org.jfree.data.gantt.TaskSeriesCollection;   public class ProgressControl {            public static String createPlanGanttChart(String missionId,String missionName,HttpSession session,PrintWriter pw){                    String fileName = null;          Connection conn = null;          Statement stmt = null;          ResultSet rs = null;          String sql = null;          String sql2 = null;                    ArrayList nameList = new ArrayList();          ArrayList startList = new ArrayList();          ArrayList endList = new ArrayList();                    conn = DB.getConnection();          stmt = DB.getStatement(conn);                    sql = "select * from SQLJ.Pro_control"; // where Task_id = '" + missionId + "'";                    //System.out.println(sql);                    rs = DB.getResultSet(stmt, sql);                    try {              while(rs.next()){                                    nameList.add(rs.getString("Task_name"));                  startList.add(rs.getDate("Plan_starttime"));                  endList.add(rs.getDate("Plan_endtime"));                                              }          } catch (SQLException e) {              // TODO Auto-generated catch block              e.printStackTrace();          }                    ListIterator iterN = nameList.listIterator();          ListIterator iterS = startList.listIterator();          ListIterator iterE = endList.listIterator();                    TaskSeriesCollection tsc = new TaskSeriesCollection();          TaskSeries tsPlan = new TaskSeries("Plan");                        while(iterN.hasNext()){                            String submissionName = (String)iterN.next();              java.util.Date sDate = (java.util.Date)iterS.next();              java.util.Date eDate = (java.util.Date)iterE.next();                                        if(sDate.before(eDate)){              Task task = new Task(submissionName,sDate,eDate);              tsPlan.add(task);              }              else{}          }              tsc.add(tsPlan);//tsc.add(tsPlan);                                JFreeChart chart = ChartFactory.createGanttChart(missionName + "GanttProject", "Project", "Time", tsc, true, true, true);              ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());                  try {                      fileName = ServletUtilities.saveChartAsPNG(chart, 500, 80+65*nameList.size(), info,session);                  } catch (IOException e) {                      // TODO Auto-generated catch block                      e.printStackTrace();                  }                            try {                      ChartUtilities.writeImageMap(pw, fileName, info,true);                  } catch (IOException e) {                      // TODO Auto-generated catch block                      e.printStackTrace();                  }                            try {                      rs.close();                      stmt.close();                      conn.close();                  } catch (SQLException e) {                      // TODO Auto-generated catch block                      e.printStackTrace();                  }                     pw.flush();          //System.out.println(fileName);          return fileName;      }      public static String createRealGanttChart(String missionId,String missionName,HttpSession session,PrintWriter pw){          String fileName = null;          Connection conn = null;          Statement stmt = null;          ResultSet rs = null;          String sql = null;          String sql2 = null;                    ArrayList nameList = new ArrayList();          ArrayList startList = new ArrayList();          ArrayList endList = new ArrayList();                    conn = DB.getConnection();          stmt = DB.getStatement(conn);                    sql = "select * from SQLJ.Pro_control"; // where Task_id = '" + missionId + "'";          //System.out.println(sql);          rs = DB.getResultSet(stmt, sql);          try {              while(rs.next()){                  nameList.add(rs.getString("Task_name"));                                  startList.add(rs.getDate("Reality_starttime"));                  endList.add(rs.getDate("Reality_endtime"));                              }          } catch (SQLException e) {              // TODO Auto-generated catch block              e.printStackTrace();          }          //rs = null;          //System.out.println("over:1");              ListIterator iterN = nameList.listIterator();          ListIterator iterS = startList.listIterator();          ListIterator iterE = endList.listIterator();          TaskSeriesCollection tsc = new TaskSeriesCollection();          //TaskSeries tsPlan = new TaskSeries("Plan");          TaskSeries tsReal = new TaskSeries("Real");          while(iterN.hasNext()){                            String submissionName = (String)iterN.next();              java.util.Date sDate = (java.util.Date)iterS.next();              java.util.Date eDate = (java.util.Date)iterE.next();                                        if(sDate.before(eDate)){                            Task task = new Task(submissionName,sDate,eDate);              tsReal.add(task);              }              else{}                       }              tsc.add(tsReal);//tsc.add(tsPlan);              JFreeChart chart = ChartFactory.createGanttChart(missionName + "GanttProject", "Project", "Time", tsc, true, true, true);              ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());                  try {                      fileName = ServletUtilities.saveChartAsPNG(chart, 500, 80+65*nameList.size(), info,session);                  } catch (IOException e) {                      // TODO Auto-generated catch block                      e.printStackTrace();                  }                  try {                      ChartUtilities.writeImageMap(pw, fileName, info,true);                  } catch (IOException e) {                      // TODO Auto-generated catch block                      e.printStackTrace();                  }                  try {                      rs.close();                      stmt.close();                      conn.close();                  } catch (SQLException e) {                      // TODO Auto-generated catch block                      e.printStackTrace();                  }                     pw.flush();          //System.out.println(fileName);          return fileName;      }  }

我把計劃任務和實際任務分開畫的甘特圖，所以有兩個甘特圖的jsp頁面

PlanGantt.jsp

<%@ page language="java" import="java.util.*,java.io.*" %> <%@ page import="com.angrybirds.DAO.ProgressControl"%> <%  String path = request.getContextPath();  String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";  %>