我正在尝试创建一个简单的 JSP 页面，该页面导入一个作为 sax 解析器的 java 类。在 XMLReader 的实例化上部署应用程序时出现错误。我已经使用 main 方法对其进行了测试，以确保 java 正常工作。我忘记了配置设置吗？下面是我的 JSP 页面和我的班级。
页面
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@page import="com.xml.XMLReader" %>
<%@page import="com.xml.Weather" %>
<%@page import="java.util.ArrayList" %>
<!DOCTYPE html>
<jsp:useBean id="xmlReader" class="XMLReader" scope="session" />
<%
XMLReader reader = new XMLReader();
ArrayList<Weather> list;
list = reader.readXML();
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Weather Application</title>
</head>
<body>
<p>test</p>
</body>
</html>
XMLReader 类缩写
public class XMLReader extends DefaultHandler implements java.io.Serializable {
//variable declarations
private Weather weather;
private ArrayList<weather> weatherList = new ArrayList<weather>();
private String data;
public XMLReader() {}
public ArrayList<CityWeather> readXML() throws ParserConfigurationException, SAXException, IOException {
SAXParserFactory saxFactory = SAXParserFactory.newInstance();
SAXParser sp = saxFactory.newSAXParser();
XMLReader handler = new XMLReader();
sp.parse("Weather.xml", handler);
return handler.getList();
}
@Override
public void startElement(String uri, String localName, String qName, Attributes attributes)
throws SAXException {
....
}
@Override
public void endElement(String uri, String localName, String qName) throws SAXException {
...
}
@Override
public void characters(char[] buffer, int start, int length) {
data = new String(buffer, start, length);
}
}
编辑：这是错误堆栈跟踪
java.lang.InstantiationException: XMLReader
at org.apache.jsp.index_jsp._jspService(index_jsp.java from :64)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:403)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:492)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:378)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:847)
at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1539)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:281)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:655)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:595)
at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:98)
at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:91)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:162)
at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:330)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:231)
at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:174)
at com.sun.grizzly.http.ProcessorTask.invokeAdapter(ProcessorTask.java:828)
at com.sun.grizzly.http.ProcessorTask.doProcess(ProcessorTask.java:725)
at com.sun.grizzly.http.ProcessorTask.process(ProcessorTask.java:1019)
at com.sun.grizzly.http.DefaultProtocolFilter.execute(DefaultProtocolFilter.java:225)
at com.sun.grizzly.DefaultProtocolChain.executeProtocolFilter(DefaultProtocolChain.java:137)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:104)
at com.sun.grizzly.DefaultProtocolChain.execute(DefaultProtocolChain.java:90)
at com.sun.grizzly.http.HttpProtocolChain.execute(HttpProtocolChain.java:79)
at com.sun.grizzly.ProtocolChainContextTask.doCall(ProtocolChainContextTask.java:54)
at com.sun.grizzly.SelectionKeyContextTask.call(SelectionKeyContextTask.java:59)
at com.sun.grizzly.ContextTask.run(ContextTask.java:71)
at com.sun.grizzly.util.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:532)
at com.sun.grizzly.util.AbstractThreadPool$Worker.run(AbstractThreadPool.java:513)
at java.lang.Thread.run(Thread.java:662)