javaWeb常用代码

Oracle连接：
public static Connection getConnection() {
String url = "jdbc:oracle:thin:@localhost:1521:orcl";
String user = "drp1";
String password = "drp1";
Connection con = null;
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
con =
DriverManager.getConnection(url,user,password);
}
catch (ClassNotFoundException e1) {
e1.printStackTrace();
}catch (SQLException e) {
e.printStackTrace();
}
return con;
}
使用dom4j读取xml文件
SAXReader reader = new SAXReader();
InputStream in =
Thread.currentThread().getContextClassLoader().getResourc eAsStream("sys-config.xml");
try {
Document doc = reader.read(in);
Element driverNameEle = (Element)
doc.selectObject("/config/db-info/driver-name");
String driverName =
driverNameEle.getStringValue();
System.out.println(driverName);
} catch (DocumentException e) {
e.printStackTrace();
}
使用ajax实例
var xmlhttp;
//生成XMLHttpRequest对象
function createXMLHttpRequest() {
xmlhttp=null;
if (window.XMLHttpRequest)
{
xmlhttp=new XMLHttpRequest();
}
else if (window.ActiveXObject)
{
xmlhttp=new ActiveXObject("Microsoft.XMLHTTP");
}
}
//用户代码的验证
function validate() {
if(trim(document.getElementById("UserId").value) != null) {
createXMLHttpRequest();
//初始化http请求参数，设置XMLHttpRequest
var url="validate_user.jsp?userId=" +
document.getElementById("userId").value +"&timestamp=" + new Date().getTime();
xmlhttp.open("get", url, true);
//设置ajax响应函数
//类似电话号码
xmlhttp.onreadystatechange=function() {
if(xmlhttp.readyState == 4) {
if(xmlhttp.status == 200) {
//将ajax引擎中返回的文本写道id号为spanUserId 的span中去
document.getElementById("spanUserId").innerHTML =
"<font color='red'>" + xmlhttp.responseText + "</font>";
}else {
alert("响应失败，错误代码为：" +
xmlhttp.status);
}
}
};
//发送信息给ajax引擎
xmlhttp.send(null);
}else {
document.getElementById("spanUserId").innerHTML = "";
}
}。