在这里，我想使用Java和JSP发送邮件。
index.html
<html>
<head>
<title>Sending Mail Through JSP</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="viewport" content="width=device-width">
</head>
<body bgcolor="khaki">
<form action="mailJSP.jsp">
<table>
<tr><td><b><font color="red">To:
</td>
<td><b><b><input type="text" name="mail" value="Enter sender mail-id"/><br/>
</td>
</tr>
<tr>
<td>
<b><font color="red">Subject:
</td>
<td>
<input type="text" name="sub" value="Enter Subject Line"><br/>
</td>
</tr>
<tr>
<td>
<b><font color="red">Message Text:
</td>
<td>
<textarea rows="12" cols="80" name="mess"></textarea><br/>
</td>
</tr>
<tr>
<td>
<input type="submit" value="Send">
</td>
<td>
<input type="reset" value="Reset">
</td>
</tr>
</table>
</form>
</body></html>
mailJSP.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@ page import="java.util.*,javax.mail.*"%>
<%@ page import="javax.mail.internet.*" %>
<%
//Creating a result for getting status that messsage is delivered or not!
String result;
// Get recipient's email-ID, message & subject-line from index.html page
final String to = request.getParameter("mail");
final String subject = request.getParameter("sub");
final String messg = request.getParameter("mess");
// Sender's email ID and password needs to be mentioned
final String from = "my mail";
final String pass = "my pass";
// Defining the gmail host
String host = "smtp.gmail.com";
// Creating Properties object
Properties props = new Properties();
// Defining properties
props.put("mail.smtp.host", host);
props.put("mail.transport.protocol", "smtp");
props.put("mail.smtp.auth", "true");
props.put("mail.smtp.starttls.enable", "true");
props.put("mail.user", from);
props.put("mail.password", pass);
props.put("mail.port", "465");
// Authorized the Session object.
Session mailSession = Session.getInstance(props, new javax.mail.Authenticator() {
@Override
protected PasswordAuthentication getPasswordAuthentication() {
return new PasswordAuthentication(from, pass);
}
});
try {
// Create a default MimeMessage object.
MimeMessage message = new MimeMessage(mailSession);
// Set From: header field of the header.
message.setFrom(new InternetAddress(from));
// Set To: header field of the header.
message.addRecipient(Message.RecipientType.TO,
new InternetAddress(to));
// Set Subject: header field
message.setSubject(subject);
// Now set the actual message
message.setText(messg);
// Send message
Transport.send(message);
result = "Your mail sent successfully....";
} catch (MessagingException mex) {
mex.printStackTrace();
result = "Error: unable to send mail....";
}
%>`enter code here`
<title>Sending Mail in JSP</title>
<h1><center><font color="blue">Sending Mail Using JSP</font></h1>
<b><center><font color="red">
<% out.println(result);%></b>
我还想补充一点，我使用Netbeans IDE和Apache Server，并且已经添加了它所需的所有jar文件，但是仍然出现Exception并以“ Unable to send”结尾。所以我很困惑我在哪里犯错了？
堆栈跟踪：
Stacktrace:
org.apache.jasper.compiler.DefaultErrorHandler.javacError(DefaultErrorHandler.java:103)
org.apache.jasper.compiler.ErrorDispatcher.javacError(ErrorDispatcher.java:366)
org.apache.jasper.compiler.JDTCompiler.generateClass(JDTCompiler.java:476)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:378)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:353)
org.apache.jasper.compiler.Compiler.compile(Compiler.java:340)
org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:657)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:357)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
例外
exception
org.apache.jasper.JasperException: Unable to compile class for JSP:
An error occurred at line: 74 in the jsp file: /mailJSP.jsp
The local variable result may not have been initialized
71: %>
72: <title>Sending Mail in JSP</title>
73: <h1><center><font color="blue">Sending Mail Using JSP</font></h1>
74: <b><center><font color="red"><% out.println(result);%></b>
希望它能增加更多信息！
最佳答案
An error occurred at line: 74 in the jsp file: /mailJSP.jsp
局部变量结果可能尚未初始化
String result = new String();
初始化变量
对于第二个例外
private final String SSL_FACTORY = "javax.net.ssl.SSLSocketFactory";
int port = 465;
if ("smtp.gmail.com".equals(host)) {
props.setProperty("mail.smtp.socketFactory.class",SSL_FACTORY);
props.setProperty("mail.smtp.socketFactory.fallback","false");
props.setProperty("mail.smtp.socketFactory.port",String.valueOf(port));
}