画面遷移

★PRG(Post-Redirect-Get)パターン

フォームの送信後に表示する画面でF5キーやブラウザの更新ボタンをクリックすることで

内容の二重送信を防ぐため

SAStruts例

/** 入力画面 */

@Execute(validator=false)

public String input() {

return "input.jsp";

}

/** 登録画面 */

@Execute(validator=true, input="input.jsp")

public String register() {

...

return "complete?redirect=true";

}

/** 完了画面 */

@Execute(validator=false)

public String complete() {

return "complete.jsp";

}

★Redirectのいろいろ

HTML

<meta http-equiv="refresh" content="0; URL='http://new-website.com'" />

JavaScript

window.location = "http://new-website.com";

Apache (mod_rewrite必須)

Redirect 301 / http://www.new-website.com

RedirectMatch 301 /blog (.*) http://www.new-website.com$1

Redirect 301 /page.html http://www.old-website/new-page.html

RewriteEngine on

RewriteCond %{REQUEST_FILENAME} !-f

RewriteCond %{REQUEST_FILENAME} !-d

RewriteRule .* 404.html [L]

Nginx

server {

listen 80;

server_name old-website.com;

return 301 $scheme://new-website.com$request_uri; }

Lighttpd

server.modules = (

"mod_redirect"

)

$HTTP["host"] =~ "^(www\.)?old-website.com$" {

url.redirect = (

"^/(.*)$" => "http://www.new-website.com/$1",

)

}

PHP

header('Location: http://www.new-website.com/', true, 301);

exit();

Node.js

var http = require ("http");

var url = require ("url");

http.createServer (function (req, res) {

var pathname = url.parse (req.url) .pathname;

res.writeHead (301,{Location: 'http://new-website.com/' + pathname});

res.end ();

}) .listen (8888);