前段时间由于项目须要使用了highcharts报表,新手能够参考http://www.hcharts.cn/,教程中有比较详细的介绍和demo。可是demo中的例子的数据都是静态数据,而在实际项目中通常数据都是从数据库加载的。
下面是我作的一个简单例子,从数据库中加载数据而后在前端使用highcharts渲染。javascript
读取数据库数据使用的servlet,能够根据须要改为其余(如spring等)。servlet主要代码以下:html
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Connection conn = null;
String sql;
String url = "jdbc:mysql://192.168.1.203:3306/test?user=opuser&password=opuser1111&useUnicode=true&characterEncoding=UTF8";
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(url);
Statement stmt = conn.createStatement();
sql = "select * from test";
ResultSet rs = stmt.executeQuery(sql);
List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
while (rs.next()) {
System.out.println(rs.getString(1) + " " + rs.getString(2) + " " + rs.getString(3));
Map<String, Object> map = new HashMap<String, Object>();
map.put("datetime", rs.getString(2));
map.put("data", Double.parseDouble(rs.getString(3)));
list.add(map);
}
Gson gson = new Gson();
String g = gson.toJson(list);
PrintWriter out = response.getWriter();
out.println(g);
out.flush();
out.close();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
本例中返回的数据格式是json。
程序中使用了mysql和gson的jar包,请自行下载。由于都是比较经常使用的jar包,在此就不提供下载地址了。前端
而后是jsp代码以下:java
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>HighChartsTest</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<!-- <script type="text/javascript" src="js/jquery-1.8.3.min.js"></script> <script type="text/javascript" src="js/highcharts.js"></script> -->
<script type="text/javascript" src="http://cdn.hcharts.cn/jquery/jquery-1.8.3.min.js"></script>
<script type="text/javascript" src="http://cdn.hcharts.cn/highcharts/highcharts.js"></script>
<script> //图表属性,不包含数据 var options = { chart: { renderTo:'container', type:'spline', }, title: { text: '实时温度曲线', x: -20 //center }, xAxis:{ }, yAxis: { title: { text: 'Temperature (°C)' }, plotLines: [{ value: 0, width: 1, color: '#808080' }] }, series: [{ name:'温度', }], tooltip: { valueSuffix: '°C' }, plotOptions: { spline:{ dataLabels: { enabled: true }, animation:false, }, }, }; //初始函数,设置定时器,定时取数据 $(function () { queryData(0); var i=0; var timer = setInterval(function(){ i++; if(i>=3) {i=0;} queryData(i); },3000); //中止刷新 $("button").click(function(){ clearInterval(timer); }); }); var categories = []; var datas = []; //Ajax 获取数据并解析建立Highcharts图表 function queryData(index) { $.ajax({ url:'servlet/HighCharts', type:'get', dataType:"json", success:function(data) { $.each(data,function(i,n){ categories[i] = n["datetime"]; datas[i] = n["data"]; }); options.xAxis.categories = categories; options.series[0].data = datas; chart = new Highcharts.Chart(options); } }); } </script>
</head>
<body>
<div id="container" style="min-width:800px;height:400px;"></div>
<p align=center><button>中止刷新</button></p>
</body>
</html>
代码下载:http://pan.baidu.com/s/1slvI6ULmysql