我得到了答案，在这里发帖可能会有所帮助其他。
的Login.jsp： -
<div class = "connect" id="gSignIn"></div>
LoginBackend.jsp： -
**<%@ page langu**age="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ page import="java.sql.*" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Login</title>
</head>
<body>
<%! String userdbName;
String userdbPsw;
String dbUserEmail;
%>
<%
Connection con= null;
PreparedStatement ps = null;
ResultSet rs = null;
String driverName = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/logindb";
String user = "root";
String dbpsw = "root";
String sql = "select * from userdetail where email=? and password=?";
String entered_name,entered_email, entered_password ;
//from form values
entered_email = request.getParameter("email");
entered_password = request.getParameter("password");
if(((entered_email!= (null) ||entered_email !=("")) && (entered_password !=(null) || entered_password !=(""))))
{
try{
Class.forName(driverName);
con = DriverManager.getConnection(url, user, dbpsw);
ps = con.prepareStatement(sql);
ps.setString(1, entered_email);
ps.setString(2, entered_password);
rs = ps.executeQuery();
if(rs.next())
{
userdbName = rs.getString("name");
dbUserEmail = rs.getString("email");
userdbPsw = rs.getString("password");
if(entered_email.equals(dbUserEmail) && entered_password.equals(userdbPsw))
{
session.setAttribute("name",userdbName);
session.setAttribute("email",dbUserEmail);
session.setAttribute("login_type","normal");
response.sendRedirect("welcome.jsp");
}
}
else
{
response.sendRedirect("error.jsp");
}
rs.close();
ps.close();
}
catch(SQLException sqe)
{
out.println(sqe);
}
}
else
{
%>
<center><p style="color:red">Error In Login</p></center>
<%
getServletContext().getRequestDispatcher("/home.jsp").include(request,
response);
}
%>
</body>
的welcome.jsp： -
!-- this google client id id for localhost -->
<meta name="google-signin-client_id" content="1015753179876-pphemvpb1o83nakb94s6na33pcjl33l8.apps.googleusercontent.com">
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Welcome</title>
<script>
function signOut() {
var auth2 = gapi.auth2.getAuthInstance();
auth2.signOut().then(function() {
console.log(gapi.auth2.getAuthInstance().isSignedIn);
console.log('User signed out.');
alert("Sign out..");
auth2.disconnect();
window.location.href = "logout.jsp";
});
}
function onLoad() {
gapi.load('auth2', function() {
gapi.auth2.init();
});
}
function facebook_logout()
{
FB.logout(function(response)
{
/* alert("log out 1 " + response);
*/ FB.getLoginStatus(function(response)
{
if (response && response.status === 'connected')
{
alert("log out " + response);
FB.logout(function(response) {
alert("log out ");
document.location.reload();
window.location.href = "logout.jsp";
});
}
});
window.location.href = "logout.jsp";
});
}
</script>
</head>
<body>
<script>
window.fbAsyncInit = function() {
FB.init({
appId : '323155731439231',
apiKey : '323155731439231',
cookie : true, // enable cookies to allow the server to access
status : true, // the session
xfbml : true, // parse social plugins on this page
version : 'v2.9' // use graph api version 2.8
});
// Now that we've initialized the JavaScript SDK, we call
// FB.getLoginStatus(). This function gets the state of the
// person visiting this page and can return one of three states to
// the callback you provide. They can be:
//
// 1. Logged into your app ('connected')
// 2. Logged into Facebook, but not your app ('not_authorized')
// 3. Not logged into Facebook and can't tell if they are logged into
// your app or not.
//
// These three cases are handled in the callback function.
FB.getLoginStatus(function(response) {
statusChangeCallback(response);
});
};
// This is called with the results from from FB.getLoginStatus().
function statusChangeCallback(response) {
console.log('statusChangeCallback');
console.log(response);
// The response object is returned with a status field that lets the
// app know the current login status of the person.
// Full docs on the response object can be found in the documentation
// for FB.getLoginStatus().
if (response.status === 'connected') {
// Logged into your app and Facebook.
testAPI();
} else {
// The person is not logged into your app or we are unable to tell.
document.getElementById('status').innerHTML = 'Please log ' +
'into this app.';
}
}
// This function is called when someone finishes with the Login
// Button. See the onlogin handler attached to it in the sample
// code below.
function checkLoginState() {
FB.getLoginStatus(function(response) {
statusChangeCallback(response);
});
}
// Load the SDK asynchronously
(function(d, s, id) {
var js, fjs = d.getElementsByTagName(s)[0];
if (d.getElementById(id)) return;
js = d.createElement(s); js.id = id;
js.src = "//connect.facebook.net/en_US/sdk.js";
fjs.parentNode.insertBefore(js, fjs);
}(document, 'script', 'facebook-jssdk'));
// Here we run a very simple test of the Graph API after login is
// successful. See statusChangeCallback() for when this call is made.
function testAPI() {
console.log('Welcome! Fetching your information.... ');
/* alert("testapi"); */
FB.api('/me?fields=id,name,email,permissions', function(response) {
console.log('Successful login for: ' + response.name);
console.log(response.email);
});
}
</script>
<%-- <p>Welcome, <%=session.getAttribute("name")%></p> --%>
<%
if(session.getAttribute("login_type")=="google")
{
System.out.println("welcome by google");
out.println("Welcome, " + session.getAttribute("name"));
%>
<a href="#" onclick="signOut();">Sign out by google</a>
<%
}
else if(session.getAttribute("login_type")=="normal")
{
out.println("Welcome, " + session.getAttribute("name"));
%>
<a href="logout.jsp">Logout_Normal</a>
<%
}
else if(session.getAttribute("login_type")=="facebook")
{
System.out.println("welcome by facebook");
out.println("Welcome, " + session.getAttribute("name"));
%>
<a href="#" onclick="facebook_logout();">Sign out by facebook</a>
<%
}
else
{
response.sendRedirect("home.jsp");
}
%>
<script src="https://apis.google.com/js/client:platform.js?onload=onLoad" async defer> </script>
<script src="js/jquery.min.js"></script>
</body>
</html>