我正在参与实时项目。
工作内容: 我从Twitter获取数据,并将输出移动到Cassandra数据库,然后使用Testrestful Web服务以JSON格式获取输出。最后,输出会在网页上显示。我使用GlassFish服务器连接Web服务和网页。这是一个实时项目,所以我每5秒刷新一次页面。
前几秒钟没有任何错误,5到10分钟后我在GlassFish服务器上遇到了以下错误:
错误: WARNING:StandardWrapperValve[genric.ApplicationConfig]:servlet genric.ApplicationConfig的Servlet.service()抛出异常 java.lang.OutOfMemoryError:Java堆空间
我不知道为什么会出现这个错误以及如何解决。 有人可以帮我吗?
这是我的Web服务代码:
public String gettweets(String st)
{
cluster=Cluster.builder().addContactPoint("localhost").build();
session=cluster.connect("space");
String query ="select * from tweet_count where createdtime='"+st+"' allow filtering;";
ResultSet result = session.execute(query);
String text = "[";
for(Row r : result){
System.out.println(r.getString("tag_name"));
text+="{\""+"x"+"\":\""+r.getString("tag_name")+"\",\""+"y"+"\":\""+r.getInt("count")+"\"},";
}
text=text.substring(0,text.length()-1);
text+="]";
return text;
}
这是我的网页代码:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
</head>
<body onload="load();grid();marqueeload();" style="background-color:white">
<pre style="height:25px;background-color:black;">
<div id = "title" style = "text-align:center;font-size:20px;width:100%;"><span>REAL TIME TWITTER TRENDS</span></div>
</pre>
<div><table>
<tr><td><lable>Select Date<lable></td><td> : </td><td><input id="datepicker" type="text" /></td></tr></table>
</div>
<div style = "width:100%">
<div id="container2" style = "width:670px;height:300px;float:left;background-color:white;border: 1px solid green;">
<div style = "text-align:center;font-size:20px;"><span1>CHART VIEW<span1></div>
<div id="container1"></div>
</div>
<div id="container3" style = "width:670px;overflow-y:auto;height:300px;float:right;background-color:white;border: 1px solid green;">
<div style = "text-align:center;font-size:20px;"><span1>GRID VIEW<span1></div>
<div id="Grid"></div>
</div>
</div>
<div style = "width:100%;border: 1px solid green;height:300px;float:left;background-color:white;">
<div style = "text-align:center;font-size:20px;"><span1>Trending tweets<span1></div>
<marquee id = "marqueeid" direction="up" height="200" scrollAmount=2 scrollDelay=130 class="sidelink" onMouseDown="this.stop()" onMouseOver="this.stop()" onMouseMove="this.stop()" onMouseOut="this.start()" vspace="10" >
</marquee>
</div>
<script type="text/javascript" language="javascript">
function marqueeload()
{
var str;
$.get("http://localhost:8080/WebApplication1/webresources/generic", function(str)
{
str=str.slice(12, str.length-14);
var div=document.getElementById('marqueeid');
div.innerHTML=str;
});
}
$(function () {
$("#datepicker").ejDatePicker({
select: "onSelected"
});
$("#datepicker").ejDatePicker({ enabled: true });
});
function onSelected(args) {
var str = args.value;
var newstr = str.split("/",3);
if(newstr[0].length == 1){
newstr[0] = '0'+newstr[0];
}
if(newstr[1].length == 1){
newstr[1] = '0'+newstr[1];
}
var dat = newstr[2]+'-'+newstr[0]+'-'+newstr[1];
window.datetweet = dat;
$("#container1").ejChart("destroy");
grid();
load();
}
function load() {
var str;
$.get("http://localhost:8080/WebApplication1/webresources/time/"+window.datetweet, function(str)
{
str=str.slice(12, str.length-14);
var data=JSON.parse(str);
$("#container1").ejChart(
{
primaryXAxis:
{
title: { text: 'Tagname' },
labelRotation: 45
},
primaryYAxis:
{
range: { min: 0, max: 1000, interval: 100 },
title: { text: 'Count' }
},
commonSeriesOptions: {
type: 'column', animation: true,
tooltipFormat: "#point.x# : #point.y#"
},
series: [
{
points: data,
}
],
load:"loadTheme",
showTooltip: true,
needResize:true,
size: { height: 300 },
legend: { visible: false, position: 'top' }
});
});
}
$(document).ready(function()
{
$("#Grid").ejGrid({
dataSource: [],
allowPaging: true,
allowSorting: true,
columns: [
{ field: "x", headerText: "Trend Name", textAlign: ej.textAlign.Right, width: 10 },
{ field: "y", headerText: "Count", textAlign: ej.textAlign.Right, width: 10 }
]
});
});
function grid()
{
var str;
var url="http://localhost:8080/WebApplication1/webresources/time/"+window.datetweet;
$.get(url, function(str)
{
str=str.slice(12, str.length-14);
var obj=JSON.parse(str);
var instance = $("#Grid").ejGrid("instance");
instance._dataManager = new ej.DataManager(obj);
$("#Grid").ejGrid("model.dataSource", instance._dataManager);
});
}
window.setInterval(function() { load(); grid(); marqueeload(); }, 10000);
</script>
</body>
</html>
session=cluster.connect("space");
打开的会话对象进行的操作,请尝试调用session.close()
以释放资源。 - Ceiling Gecko