在給Javabean屬性賦值時報錯500

HTTP Status 500 – Internal Server Error

Type?Exception Report

Message?/FirstDemo.jsp (line: [10], column: [0]) The value for the useBean class attribute [java.Person] is invalid.

Description?The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

org.apache.jasper.JasperException:?/FirstDemo.jsp?(line:?[10],?column:?[0])?The?value?for?the?useBean?class?attribute?[java.Person]?is?invalid.
	org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:42)
	org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:292)
	org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:115)
	org.apache.jasper.compiler.Generator$GenerateVisitor.visit(Generator.java:1383)
	org.apache.jasper.compiler.Node$UseBean.accept(Node.java:1186)
	org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2389)
	org.apache.jasper.compiler.Node$Visitor.visitBody(Node.java:2441)
	org.apache.jasper.compiler.Node$Visitor.visit(Node.java:2447)
	org.apache.jasper.compiler.Node$Root.accept(Node.java:470)
	org.apache.jasper.compiler.Node$Nodes.visit(Node.java:2389)
	org.apache.jasper.compiler.Generator.generate(Generator.java:3667)
	org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:257)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:385)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:362)
	org.apache.jasper.compiler.Compiler.compile(Compiler.java:346)
	org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:603)
	org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)
	org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:386)
	org.apache.jasper.servlet.JspServlet.service(JspServlet.java:330)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
	org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Note?The full stack trace of the root cause is available in the server logs.

Apache Tomcat/9.0.8

下面是自己的代碼部分：

<%--
??Created?by?IntelliJ?IDEA.
??User:?lihao
??Date:?2018/7/29
??Time:?20:13
??To?change?this?template?use?File?|?Settings?|?File?Templates.
--%>
<%@?page?contentType="text/html;charset=UTF-8"?language="java"?%>
<%@?taglib?prefix="c"?uri="http://java.sun.com/jsp/jstl/core"?%>
<jsp:useBean?id="person"?class="java.Person"/>
<html>
<head>
????<title>Title</title>
</head>
<body>
<c:set?target="${person}"?property="password"?value="1234"/>
<c:set?target="${person}"?property="username"?value="223"/>
<c:out?value="${person.username}"/>
<c:out?value="${person.password}"/>
</body>
</html>

package?java;
public?class?Person?{
????private?String?username;
????private?String?password;

????public?String?getUsername()?{
????????return?username;
????}

????public?void?setUsername(String?username)?{
????????this.username?=?username;
????}

????public?String?getPassword()?{
????????return?password;
????}

????public?void?setPassword(String?password)?{
????????this.password?=?password;
????}
}