2009年8月2日 星期日

JSP實作MD5

有用過PHP的人都知道,如果要做Hash的話,本身就有Function可以執行,很方便,但在JSP中卻沒有,需要手動來處理:

<%@page contentType="text/html" pageEncoding="UTF-8" import="java.security.*"%>
<!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=UTF-8">
<title>JSP Page</title>
</head>
<body>
<%
String plainText = "123456";
MessageDigest mdAlgorithm = MessageDigest.getInstance("MD5");
mdAlgorithm.update(plainText.getBytes());
byte[] digest = mdAlgorithm.digest();
StringBuffer hexString = new StringBuffer();
for (int i = 0; i < digest.length; i++) {
plainText = Integer.toHexString(0xFF & digest[i]);

if (plainText.length() < 2) {
plainText = "0" + plainText;
}
hexString.append(plainText);
}
out.print(hexString.toString());
%>
</body>
</html>

資料來源:
http://snook.ca/archives/java/create_md5_hash/
http://blog.xuite.net/jameschih/java/5089658