JAVA中如何通过XML来配置数据库的连接参数?

想法是好的，在SPRING框架中可以很好的实现

好了.我解决了~~
真TNND是个麻烦的问题...
从网上找了一堆不完整的代码,东拼西凑.总算完成了我的想法...
稍后我把总结出来的经验和源代码贴上来...这可真TNND是个麻烦东西....

将数据库链接的那些参数写入固定格式的XML文件，然后运行程序时候读XML，后台拼接字符串
我做过一个类似的，至少是可行的import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import javax.xml.parsers.*;
import javax.xml.transform.*;
import org.w3c.dom.*;
import org.xml.sax.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;public class CreateXMLForEnterServelet extends HttpServlet {
    private static final String CONTENT_TYPE = "text/html; charset=GBK";    //Initialize global variables
    public void init() throws ServletException {
    }    //Process the HTTP Get request
    public void doGet(HttpServletRequest request, HttpServletResponse response) throws
            ServletException, IOException {
        response.setContentType(CONTENT_TYPE);
        PrintWriter out = response.getWriter();
        //获取传递过来的值
        String databaseType = request.getParameter("select");
        String userName = request.getParameter("userName");
        String userPassword = request.getParameter("userPassword");
        String dbName = request.getParameter("dbName");
        String dbSouse = request.getParameter("dbSouces");
        int port = Integer.parseInt(request.getParameter("portNum"));
        Document doc;
        Element root;
        try
        {
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            DocumentBuilder db = dbf.newDocumentBuilder();
            String path = request.getRealPath("/");
            File file = new File( path + "/" + "DBInfo.xml");
            if(!file.exists())
            {
                doc = db.newDocument();
                root = doc.createElement("DBInfo");
                doc.appendChild(root);
            }
            else
            {
                doc = db.parse(file);
                root = doc.getDocumentElement();
            }
            //添加子节点
            Element rowNode = doc.createElement(databaseType);
            root.appendChild(rowNode);
            Node node = doc.createElement("Driver");
            Node nodestr = doc.createElement("ConnectString");
            Node serverName = doc.createElement("ServerName");
            Node nodeName = doc.createElement("UserName");
            Node nodePWD = doc.createElement("PassWord");
            Node nodePort = doc.createElement("Port");
            Node nodeDB = doc.createElement("DataBase");            rowNode.appendChild(node);
            rowNode.appendChild(nodestr);
            rowNode.appendChild(serverName);
            rowNode.appendChild(nodeDB);
            rowNode.appendChild(nodeName);
            rowNode.appendChild(nodePWD);
            rowNode.appendChild(nodePort);            String nodeValue;//Driver
            String nodeConStr;//连接字符串
            if(databaseType.equals("ORACLE"))
            {
               nodeValue = "oracle.jdbc.driver.OracleDriver";
               nodeConStr = "jdbc:oracle:thin";
            }
            else
            {
                nodeValue = "com.microsoft.jdbc.sqlserver.SQLServerDriver";
                nodeConStr = "jdbc:microsoft:sqlserver";
            }
            Text text = doc.createTextNode(nodeValue);
            Text textstr = doc.createTextNode(nodeConStr);
            Text textName = doc.createTextNode(userName);
            Text textPWD = doc.createTextNode(userPassword);
            Text textServer = doc.createTextNode(dbName);
            Text textPort = doc.createTextNode(String.valueOf(port));
            Text textDB = doc.createTextNode(dbSouse);            node.appendChild(text);
            nodestr.appendChild(textstr);
            nodeName.appendChild(textName);
            nodePWD.appendChild(textPWD);
            serverName.appendChild(textServer);
            nodePort.appendChild(textPort);
            nodeDB.appendChild(textDB);            DOMSource doms = new DOMSource(doc);            StreamResult sr = null;            TransformerFactory tff = TransformerFactory.newInstance();
            Transformer tf = tff.newTransformer();
            sr = new StreamResult(file);
            tf.transform(doms,sr);
            out.println("<h1>Create XMLFile Is Ok!!</h1>");
            request.getRequestDispatcher("index.jsp").forward(request,response);
        }
        catch(Exception ex)
        {
            out.println("<h1>生成 XML 配置文件时出现错误：</h1><br/><h4>"+ex+"</h4>");
            out.println("<br/><br/>");
            out.print("<a href='index.jsp'>【点这里回到首页】</a>");        }        out.close();    }    //Process the HTTP Post request
    public void doPost(HttpServletRequest request, HttpServletResponse response) throws
            ServletException, IOException {
        doGet(request, response);
    }    //Clean up resources
    public void destroy() {
    }
}

楼上的，强！
不过你这样写也还是只限于Oracle 和 MSSQL ，其实你更应该读个已经存在的XML,自己写个DTD文件来固定格式，这样才是真正意义的扩展，可以添加任意类型的DB。不过现在Spring已经解决了

我解决了...我用JBULIDER 2006写的...
我的代码如下:
mysqlConfig.xml
[BanUBB]
<?xml version="1.0" encoding="UTF-8"?>
  服务器名称或地址
serverport      -->  服务器端口
databasename  -->  数据库名
username   -->  数据库帐号
password   -->  数据库密码
-->
<reportenv>
  <datasource>
    <servername>127.0.0.1</servername>
    <serverport>3306</serverport>
    <databasename>ragnarok</databasename>
    <username>root</username>
    <password>hackcity</password>
  </datasource>
</reportenv>
[/BanUBB]ConfigParser.java [BanUBB]
package roadmin.Conn;
import java.util.Properties;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
class ConfigParser extends DefaultHandler {
    //定义一个Properties 用来存放属性值
    private Properties props;
    private String currentSet;
    private String currentName;
    private StringBuffer currentValue = new StringBuffer();
    // 构建器初始化props
    public ConfigParser() {
        this.props = new Properties();
    }
    public Properties getProps() {
        return this.props;
    }
    // 定义开始解析元素的方法. 这里是将<xxx>中的名称xxx提取出来.
    public void startElement(String uri, String localName, String qName,
                             Attributes attributes) throws SAXException {
        currentValue.delete(0, currentValue.length());
        this.currentName = qName;
    }
    // 这里是将<xxx></xxx>之间的值加入到currentValue
    public void characters(char[] ch, int start, int length) throws
            SAXException {
        currentValue.append(ch, start, length);
    }
    // 在遇到</xxx>结束后,将之前的名称和值一一对应保存在props中
    public void endElement(String uri, String localName, String qName) throws
            SAXException {
        props.put(qName.toLowerCase(), currentValue.toString().trim());
    }
} [/BanUBB]
ParseXML.java [BanUBB]
package roadmin.Conn;
import java.util.Properties;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
class ParseXML {
    // 定义一个Properties 用来存放属性值
    private Properties props;
    public Properties getProps() {
        return this.props;
    }
    public void parse(String filename) throws Exception {
        // 将我们的解析器对象化
        ConfigParser handler = new ConfigParser();
        // 获取SAX工厂对象
        SAXParserFactory factory = SAXParserFactory.newInstance();
        factory.setNamespaceAware(false);
        factory.setValidating(false);
        // 获取SAX解析
        SAXParser parser = factory.newSAXParser();
        try {
            // 将解析器和解析对象xml联系起来,开始解析
            parser.parse(filename, handler);
            // 获取解析成功后的属性
            props = handler.getProps();
        } finally {
            factory = null;
            parser = null;
            handler = null;
        }
    }
} [/BanUBB]ReadConfigXml.java[BanUBB]
package roadmin.Conn;
import java.util.Properties;
public class ReadConfigXml {
    private Properties props;
    public ReadConfigXml(String url) {
        ParseXML myRead = new ParseXML();
        try {
            myRead.parse(url);
            props = new Properties();
            props = myRead.getProps();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    public String getServerName() {
        return props.getProperty("servername");
    }
    public String getServerPort() {
        return props.getProperty("serverport");
    }
    public String getDatabaseName() {
        return props.getProperty("databasename");
    }
    public String getUserName() {
        return props.getProperty("username");
    }
    public String getPassWord() {
        return props.getProperty("password");
    }
} [/BanUBB]DataBase.java [BanUBB]
package roadmin.Conn;
import java.sql.*;
import roadmin.Conn.ReadConfigXml;
import javax.servlet.ServletContext;
public class DataBase {
    private Connection Conn;
    public DataBase() {
    }
    public static DataBase newInstance() {
        return new DataBase();
    }
    public Connection getConn() {
        ReadConfigXml xml = new ReadConfigXml("../RoAdmin/WEB-INF/classes/mysqlConfig.xml");
        String dbhost = xml.getServerName();
        String dbName = xml.getDatabaseName();
        String dbUser = xml.getUserName();
        String dbPass = xml.getPassWord();
        String dbDriver = "org.gjt.mm.mysql.Driver";
        String dbURL = "jdbc:mysql://" + dbhost + "/" + dbName + "?user="
                       + dbUser + "&password=" + dbPass
                       + "&autoRec&failOverRead";
        try {
            Class.forName(dbDriver);
            Conn = DriverManager.getConnection(dbURL);
        } catch (SQLException ex) {
            ex.printStackTrace();
        } catch (ClassNotFoundException ex1) {
            ex1.printStackTrace();
        }
        return Conn;
    }
}
[/BanUBB]

补充一下:ReadConfigXml.java 和 DataBase.java 是我自己被充的.前面两个类是网上流传的...

调试易

JAVA中如何通过XML来配置数据库的连接参数?

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