用xml配置连接数据库

实现功能：

           1，在XML文件里配置数据库连接（能修改数据库连接相关参数，如用户名等）

           2，同时配置两个数据库连接

           3，除连接数数据库参数外，其他参数的传送

参考资料：

xml 数据库连接信息 配置与读取(dom4j) - hzh的日志 - 网易博客
http://blog.163.com/woshihezhonghua@126/blog/static/1271436362010510253725/

具体代码：

1，sys-config.xml
需要的jar包：sqljdbc4.jar，ojdbc14.jar

<?xml version="1.0" encoding="UTF-8"?>
<config>
<db-info id="01">
<!—— jdbc链接Oracle数据库 ——>
<orcldriver-name>oracle.jdbc.driver.OracleDriver</orcldriver-name>
<orclurl>jdbc:oracle:thin:@111.111.1.11:1521/orcl</orclurl>
<orclusername>201</orclusername>
<orclpassword>300</orclpassword>
<orclmandt>006</orclmandt>
<orcldays>10</orcldays><!-- 查几天前到现在的数据 -->
<orclpasesize>10</orclpasesize><!-- 每页显示数 -->
<orclrefreshTime>6</orclrefreshTime><!--翻页间隔  -->
<orclpageRefresh>10</orclpageRefresh><!--页面刷新  -->
</db-info>
<!—— jdbc链接SQL server数据库 ——>
<db-info id="00">
<driver-name>com.microsoft.sqlserver.jdbc.SQLServerDriver</driver-name>
<url>jdbc:sqlserver://222.222.0.222:1433;DatabaseName=1111</url>
<username>b</username>
<password>b</password>
</db-info>
</config>

2，将要传递的参数实例化

OrclJdbcInfo.java

package utils;

public class OrclJdbcInfo {

private String orcldriverName;
private String orclurl;
private String orclusername;
private String orclpassword;
private String orcldays;
private String orclmandt;
private String orclpasesize;
private String orclrefreshTime;
private String orclpageRefresh;

// 注解，能在编译期间发现错误
@Override
public String toString()
{
// TODO Auto-ge
dc85
nerated method stub
return this.getClass().getName() + "{orcldriverName=" + this.orcldriverName
+ ",orclurl=" + this.orclurl + ",orclusername=" + this.orclusername
+ ",orclpassword=" + this.orclpassword + ",orcldays="+this.orcldays
+",orclmandt="+this.orclmandt+",orclpagesize="+this.orclpasesize
+",orclrefreshtime="+this.orclrefreshTime+",orclpageRefresh="+this.orclpageRefresh+"}";

}

public String getOrclrefreshTime() {
return orclrefreshTime;
}

public void setOrclrefreshTime(String orclrefreshTime) {
this.orclrefreshTime = orclrefreshTime;
}

public String getOrclpageRefresh() {
return orclpageRefresh;
}

public void setOrclpageRefresh(String orclpageRefresh) {
this.orclpageRefresh = orclpageRefresh;
}

public String getOrclpasesize() {
return orclpasesize;
}
public void setOrclpasesize(String orclpasesize) {
this.orclpasesize = orclpasesize;
}
public String getOrcldriverName() {
return orcldriverName;
}
public void setOrcldriverName(String orcldriverName) {
this.orcldriverName = orcldriverName;
}
public String getOrclurl() {
return orclurl;
}
public void setOrclurl(String orclurl) {
this.orclurl = orclurl;
}
public String getOrclusername() {
return orclusername;
}
public void setOrclusername(String orclusername) {
this.orclusername = orclusername;
}
public String getOrclpassword() {
return orclpassword;
}
public void setOrclpassword(String orclpassword) {
this.orclpassword = orclpassword;
}
public String getOrcldays() {
return orcldays;
}
public void setOrcldays(String orcldays) {
this.orcldays = orcldays;
}
public String getOrclmandt() {
return orclmandt;
}
public void setOrclmandt(String orclmandt) {
this.orclmandt = orclmandt;
}

}

JdbcInfo.java

package utils;

public class JdbcInfo {
private String driverName;
private String url;
private String username;
private String password;

// 注解，能在编译期间发现错误
@Override
public String toString() {
// TODO Auto-generated method stub
return this.getClass().getName() + "{driverName=" + this.driverName
+ ",url=" + this.url + ",username=" + this.username
+ ",password=" + this.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;
}
}

3，解析XML

ConfigReader.java
需要的jar包：dom4j-1.6.1.jar

package utils;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

/*
* 讀取xml配置文件sys-config.xml
* 採用單例模式
*/
public class ConfigReader {
private static ConfigReader instance = new ConfigReader();
private Document doc;
private JdbcInfo jdbcInfo;
private OrclJdbcInfo orclJdbcInfo;
private ConfigReader() {
try {
doc = new SAXReader().read(Thread.currentThread() .getContextClassLoader().getResourceAsStream("sys-config.xml"));

jdbcInfo = new JdbcInfo();
orclJdbcInfo = new OrclJdbcInfo();

Element driverNameElt = (Element)doc.selectObject("/config/db-info/driver-name");
Element urlElt = (Element)doc.selectObject("/config/db-info/url");
Element usernameElt = (Element)doc.selectObject("/config/db-info/username");
Element passwordElt = (Element)doc.selectObject("/config/db-info/password");

jdbcInfo.setDriverName(driverNameElt.getStringValue());
jdbcInfo.setUrl(urlElt.getStringValue());
jdbcInfo.setUsername(usernameElt.getStringValue());
jdbcInfo.setPassword(passwordElt.getStringValue());

Element orcldriverNameElt = (Element)doc.selectObject("/config/db-info/orcldriver-name");
Element orclurlElt = (Element)doc.selectObject("/config/db-info/orclurl");
Element orclusernameElt = (Element)doc.selectObject("/config/db-info/orclusername");
Element orclpasswordElt = (Element)doc.selectObject("/config/db-info/orclpassword");
Element orcldaysElt = (Element)doc.selectObject("/config/db-info/orcldays");
Element orclmandtElt = (Element)doc.selectObject("/config/db-info/orclmandt");
Element orclpasesizeElt = (Element)doc.selectObject("/config/db-info/orclpasesize");
Element orclrefreshTimeElt = (Element)doc.selectObject("/config/db-info/orclrefreshTime");
Element orclpageRefreshElt = (Element)doc.selectObject("/config/db-info/orclpageRefresh");

orclJdbcInfo.setOrcldriverName(orcldriverNameElt.getStringValue());
orclJdbcInfo.setOrclurl(orclurlElt.getStringValue());
orclJdbcInfo.setOrclusername(orclusernameElt.getStringValue());
orclJdbcInfo.setOrclpassword(orclpasswordElt.getStringValue());
orclJdbcInfo.setOrcldays(orcldaysElt.getStringValue());
orclJdbcInfo.setOrclmandt(orclmandtElt.getStringValue());
orclJdbcInfo.setOrclpasesize(orclpasesizeElt.getStringValue());
orclJdbcInfo.setOrclrefreshTime(orclrefreshTimeElt.getStringValue());
orclJdbcInfo.setOrclpageRefresh(orclpageRefreshElt.getStringValue());
} catch (DocumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

public static ConfigReader getInstance() {
return instance;
}

public JdbcInfo getjdbcInfo(){
return jdbcInfo;
}

public OrclJdbcInfo getorclJdbcInfo(){
return orclJdbcInfo;
}

//用於測試是否成功讀取數據
public static void main(String[] args) {
System.out.println(ConfigReader.getInstance().getjdbcInfo());
System.out.println(ConfigReader.getInstance().getorclJdbcInfo());
}
}

4，实现类

DBUtil.java

package utils;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServlet;

import entity.Sap;

/**
* 数据库工具类
*
* @author Administrator
*
*/
public class DBUtil extends HttpServlet{

/**
* 取得数据库连接
*
* @return
*/
//map方法封装值
public static Map getConnection() {
Map map = new HashMap() ;
Connection orclConn = null;
Connection conn = null;
try {
JdbcInfo jdbcInfo = ConfigReader.getInstance().getjdbcInfo();
Class.forName(jdbcInfo.getDriverName());
conn = DriverManager.getConnection(jdbcInfo.getUrl(), jdbcInfo.getUsername(), jdbcInfo.getPassword());

OrclJdbcInfo orclJdbcInfo = ConfigReader.getInstance().getorclJdbcInfo();
Class.forName(orclJdbcInfo.getOrcldriverName());
orclConn = DriverManager.getConnection(orclJdbcInfo.getOrclurl(), orclJdbcInfo.getOrclusername(), orclJdbcInfo.getOrclpassword());

map.put("orcldays",orclJdbcInfo.getOrcldays());
map.put("orclmandt",orclJdbcInfo.getOrclmandt());
map.put("orclpasesize",orclJdbcInfo.getOrclpasesize());
map.put("orclrefreshTime",orclJdbcInfo.getOrclrefreshTime());
map.put("orclpageRefresh",orclJdbcInfo.getOrclpageRefresh());

} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}

map.put("orclConn", orclConn);
map.put("conn", conn);

return map;

}

public static void close(PreparedStatement pstmt) {
if (pstmt != null) {
try {
pstmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void close(Statement stmt) {
if (stmt != null) {
try {
stmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void close(Connection conn) {
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void close(ResultSet rs) {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void commit(Connection conn) {
if (conn != null) {
try {
conn.commit();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void rollback(Connection conn) {
if (conn != null) {
try {
conn.rollback();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

public static void setAutoCommit(Connection conn, boolean autoCommit) {
if (conn != null) {
try {
conn.setAutoCommit(autoCommit);
} catch (SQLException e) {
e.printStackTrace();
}
}
}

//测试是否连接成功
public static void main(String[] args) {
DBUtil.getConnection();
System.out.println("---------ok---------");
}
}