XML配置文件的读取--DOM4J

<?xml version="1.0" encoding="UTF-8"?>
<config>
<db-info>
<driver-name>com.mysql.jdbc.Driver</driver-name>
<url>jdbc:mysql://localhost/yingshe</url>
<user-name></user-name>
<password></password>
</db-info>
</config>

package com.bjpowernode.drp.util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

/**
* 封装数据常用操作
* @author Administrator
*/
public class DbUtil {
public static Connection getConnection(){
Connection conn = null;
JdbcConnConfig config = XmlConfigReader.getInstance().getJdbcConnConfig();

String driverName = config.getDriverName();
String url = config.getUrl();
String userName = config.getUserName();
String password = config.getPassword();

try {
Class.forName(driverName);
conn = DriverManager.getConnection(url, userName, password);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}

return conn;
}
}

package com.bjpowernode.drp.util;

public class JdbcConnConfig {
private String driverName ;
private String url ;
private String userName ;
private String password ;

public String getDriverName() {
return driverName;
}
public void setDriverName(String driverName) {
this.driverName = driverName;
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
return "[ driverName:" + driverName + ", url:" + url + ", userName:" + userName + " ]";
}
}

package com.bjpowernode.drp.util;

import java.io.InputStream;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Node;
import org.dom4j.io.SAXReader;

public class XmlConfigReader {
//延时加载
private static XmlConfigReader instance = null;

private JdbcConnConfig conn = new JdbcConnConfig();

private XmlConfigReader(){
SAXReader reader = new SAXReader();
//装载XML文件--按资源加载的方式加载
InputStream in = Thread.currentThread().getContextClassLoader().getResourceAsStream("sys-config.xml");
try {
//把输入流的文件存入文档对象中
Document doc = reader.read(in);
Node node = (Node) doc.selectObject("/config/db-info");
String driverName = node.valueOf("driver-name");
String url = node.valueOf("url");
String userName = node.valueOf("user-name");
String password = node.valueOf("password");

conn.setDriverName(driverName);
conn.setUrl(url);
conn.setUserName(userName);
conn.setPassword(password);
} catch (DocumentException e) {
e.printStackTrace();
}
}

public  static synchronized XmlConfigReader getInstance(){
if(instance == null){
instance = new XmlConfigReader();
}
return instance;
}

/**
* 返回JDBC连接配置
*/
public JdbcConnConfig getJdbcConnConfig(){
return conn;
}
}