在给Javabean属性赋值时报错500

来源：3-1 JSTL标签之out标签

JeasonLeeHao

2018-07-29 21:24

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

下面是自己的代码部分：

<%--
  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;
    }
}

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