java通過屬性檔案調用資料庫

標籤：com   input   檔案   throws   sqlserver   eclipse   column   檔案中   array   

import java.io.IOException;import java.io.InputStream;import java.sql.*;import java.util.ArrayList;import java.util.List;import java.util.Properties;public class DAOHelper {/*** * * @param args*/public static void main(String []args){DAOHelper de=new DAOHelper();String sql="select * from users";List<Object[]> list=de.queryList(sql, null);for(int i=0;i<list.size();i++){ Object []obj=list.get(i);System.out.println(obj[1].toString()+" "+obj[2].toString());}}//    oracle串連屬性設定private static String driver;private static String url;private static String user;private static String passwd; //串連類和介面    Connection ct;PreparedStatement ps;ResultSet rs;//    讀取屬性檔案初始化資料庫連接變數static { Properties pp=new Properties();InputStream fis = DAOHelper.class.getClassLoader().getResourceAsStream("derby.properties");try {pp.load(fis);driver=pp.getProperty("driver");url=pp.getProperty("url");user=pp.getProperty("username");passwd=pp.getProperty("password");} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{if(pp!=null) pp.clear();try {if(fis!=null) fis.close();} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}public DAOHelper(){try {Class.forName(driver);ct=DriverManager.getConnection(url,user,passwd);    } catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}}public int Update(String sql,String []paras){int count=0;try {ps=ct.prepareStatement(sql);//    注入參數this.setParameters(paras);//    獲得更新資料行數。count=ps.executeUpdate() ;    } catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{this.close();}return count;}/*** @param sql* @param paras 沒有注入參數可為null或空串。* @return 返回一個ResultSet結果集。*/public ResultSet query(String sql,String[] paras){try {ps=ct.prepareStatement(sql);this.setParameters(paras);rs=ps.executeQuery();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{//不能關。}return rs;    }/*** @param sql* @param paras 沒有注入參數可為null或空串。* @return 返回一個裝有對象數組的List。*/public List queryList(String sql,String []paras){List<Object[]> list=new ArrayList<Object[]>();try {ps=ct.prepareStatement(sql);this.setParameters(paras);rs=ps.executeQuery(); ResultSetMetaData rsmd=(ResultSetMetaData) rs.getMetaData();int count=rsmd.getColumnCount();// 將查詢結果放入對象數組中。while(rs.next()) { int rows= rs.getRow();Object obj[]=new Object[count]; for(int j=0;j<count;j++){ obj[j]=rs.getString(j+1);}list.add(obj);}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{ this.close(); }return list;}public void close(){try {if(rs!=null)    rs.close();if(ps!=null) ps.close();if(ct!=null) ct.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}private void setParameters(String[] paras) throws SQLException {if(paras!=null && !paras.equals("")){    for(int i=0;i<paras.length;i++){ps.setString(i+1, paras[i]);}}}}

 屬性檔案sql.properties

username=sapassword=bbc223344url=jdbc\:sqlserver\://192.168.1.109\:142;databaseName\=QqDBdriver=com.microsoft.sqlserver.jdbc.SQLServerDriver

 

derby.properties

username=classiccarspassword=classiccarsurl=jdbc\:derby\://localhost\:1527/myeclipsedriver=org.apache.derby.jdbc.ClientDriver

mysql.properties

username=rootpassword=1234url=jdbc\:mysql\://192.168.1.114\:3306/testdriver=com.mysql.jdbc.Driver

oracle.properties

username=scottpassword=1234url=jdbc\:oracle\:thin\:@192.168.1.114\:1521\:oracle1driver=oracle.jdbc.driver.OracleDriver

 

ps：屬性檔案中的ip地址、使用者名稱和密碼需要酌情修改

java通過屬性檔案調用資料庫