Log4j与单例模式连接数据库通用类
import?java.sql.ResultSet;
import?java.sql.SQLException;
import?java.sql.Statement;
/*
?*?@ClassName: SqlHelper
?*/
public?class?SqlHelper {
????/**
??? ?*?设置单例
??? ?*?单例模式可以节省资源.
??? ?*/
????public?static?SqlHelper?instance?=?new?SqlHelper();
?
????/**
??? ?*?设置单例的一个实例方法
??? ?*
??? ?*?@return
??? ?*/
????public?static?SqlHelper getInstance() {
???????if?(instance?==?null) {
???????????//锁定当前类
???????????synchronized?(SqlHelper.class) {
??????????????instance?=?new?SqlHelper();
?????????? }
?????? }
???????return?instance;
??? }
????/**
??? ?*?得到MySql连接
??? ?*?@return
??? ?*/
????public?static?Connection getMySqlConnection() {
?????? Connection conn =?null;
?????? String url =?"jdbc:mysql://127.0.0.1:3306/ssh?useUnicode=true&characterEncoding=utf-8";
?????? String user =?"root";
?????? String password =?"root";
?????? String driver =?"com.mysql.jdbc.Driver";
???????try?{
?????????? Class.forName(driver);
?????????? conn = DriverManager.getConnection(url, user,password);
?????? }?catch?(Exception e) {
?????????? System.out.println("连接数据库出现异常"?+ e.getMessage());
?????? }
???????return?conn;
??? }
?
????/**
??? ?*?得到MSSQL连接
??? ?*?@return
??? ?*/
????public?static?Connection getMSSQLConnection() {
?????? String url =?"jdbc:sqlserver://localhost:1433;DatabaseName=test";
?????? String user =?"sa";
?????? String password =?"admin1988";
?????? String Driver =?"com.microsoft.sqlserver.jdbc.SQLServerDriver";
?????? Connection conn =?null;
???????try?{
?????????? Class.forName(Driver);
?????????? conn = DriverManager.getConnection(url, user,password);
?????? }?catch?(Exception e) {
?????????? System.out.println("连接数据库出现异常"?+ e.getMessage());
?????? }
???????return?conn;
??? }
?
????/**
??? ?*?得到Oracle连接
??? ?*?@return
??? ?*/
????public?static?Connection getOracleConnection() {
?????? String url =?"jdbc:oracle:thin:@127.0.0.1:1521:orcl";
?????? String user =?"scott";
?????? String password =?"scott";
?????? String Driver =?"oracle.jdbc.driver.OracleDriver";
?????? Connection conn =?null;
???????try?{
?????????? Class.forName(Driver);
?????????? conn = DriverManager.getConnection(url, user,password);
?????? }?catch?(Exception e) {
?????????? System.out.println("连接数据库出现异常"?+ e.getMessage());
?????? }
???????return?conn;
??? }
?
????/***
??? ?*?释放资源...
??? ?*?@param?rs
??? ?*?@param?st
??? ?*?@param?conn
??? ?*/
????public?static?void?Relesae(ResultSet rs, Statement st, Connection conn) {
???????try?{
???????????if?(rs !=?null)
????????????? rs.close();
???????????if?(st !=?null)
????????????? st.close();
???????????if?(conn !=?null)
????????????? conn.close();
?????? }?catch?(SQLException e) {
?????????? e.printStackTrace();
?????? }
??? }
}
?===============================================需要那个DataBase就开那个数据库===================================
?
#MySQL DataBase Connection?Config
driver=com.mysql.jdbc.Driver
url=jdbc\:mysql\://localhost\:3306/test?useUnicode\=true&characterEncoding\=utf-8
username=root
password=root
?
#SqlServer DataBaseConnection Config
?
#driver=com.microsoft.sqlserver.jdbc.SQLServerDriver
#url=jdbc:sqlserver://localhost:1433;DatabaseName=jdbc
#username=sa
#password=sa
?
#Oracle DataBase ConnectionConfig
#driver=oracle.jdbc.driver.OracleDriver
#url=jdbc:oracle:thin:@127.0.0.1:1521:orcl
#username=scott
#password=scott?
===================================================================================================
?
package utility;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import org.apache.log4j.PropertyConfigurator;
/**
?* 需要一个log4j.jar包
?* 扩展性稍微好点.
?*/
public class ConfigHelper {
protected static Connection conn = null;
protected ?static Properties pro = null;
protected ?static InputStream is = null;
/**得到配置的key
* @param key
* @return
*/
public static String getConfigKey(String key) {
String strVal = "";
try {
is = new FileInputStream(new File(
"src/application/jdbc_config.properties"));
pro = new Properties();
pro.load(is);
PropertyConfigurator.configure(pro);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
strVal = (String) pro.getProperty(key);
return strVal;
}
/**
* 得到连接
* @return
*/
public static Connection getConnection() {
String driver = getConfigKey("driver");
String url = getConfigKey("url");
String username = getConfigKey("username");
String password = getConfigKey("password");
try {
Class.forName(driver);
conn = DriverManager.getConnection(url, username, password);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
/**
* ?释放资源...
* @param rs
* @param stmt
* @param conn
*/
public void ?ReleaseSoucre(ResultSet rs,Statement stmt, Connection conn){
try {
if(rs!=null)
rs.close();
if(stmt!=null)
stmt.close();
if(conn!=null)
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
