java JDBC包装类

package oracle; import java.io.FileNotFoundException; import java.io.IOException; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.ResultSetMetaData; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.List; import java.util.Properties; public class DBManager{ private static Properties p=new Properties(); private static DBManager db=null; private String server; private String port; private String type; private String database; private String username; private String password; private Connection con=null; public synchronized static DBManager getInstance(){ return db==null?new DBManager():db; } private DBManager(){ try { p.load(this.getClass().getClassLoader().getResourceAsStream("config/DBCon.properties")); this.server=p.getProperty("server"); this.port=p.getProperty("port"); this.type=p.getProperty("type"); this.database=p.getProperty("database"); this.username=p.getProperty("username"); this.password=p.getProperty("password"); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } getConnection(); } private Connection getConnection(){ if(con!=null) return con; String url=null; try { if(type.equalsIgnoreCase("oracle")){ url="jdbc:oracle:thin:@"+server+":"+port+":"+database; Class.forName("oracle.jdbc.driver.OracleDriver"); }else if(type.equalsIgnoreCase("mysql")){ url="jdbc:mysql://"+server+":"+port+"/"+database; Class.forName("com.mysql.jdbc.Driver"); }else if(type.equalsIgnoreCase("sqlserver")){ url="jdbc:sqlserver://"+server+":"+port+";"+"database="+database; Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver"); } con=DriverManager.getConnection(url, username, password); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } return con; } public Statement getStatement(){ java.sql.Statement st=null; try { st=getConnection().createStatement(); } catch (SQLException e) { e.printStackTrace(); } return st; } public PreparedStatement getPreparedStatement(String sql){ PreparedStatement pst=null; try { pst=getConnection().prepareStatement(sql); } catch (SQLException e) { e.printStackTrace(); } return pst; } public <T> int executeSql(PreparedStatement pst,List<T> values){ int affect=0; try { for(int i=0;i<values.size();i++){ pst.setObject(i+1, values.get(i)); } affect=pst.executeUpdate(); pst.close(); } catch (SQLException e) { e.printStackTrace(); } return affect; } public ResultSet executeQuery(String sql,List<Object> values){ ResultSet rs=null; try { PreparedStatement pst=getConnection().prepareStatement(sql); for(int i=0;i<values.size();i++){ pst.setObject(i+1, values.get(i)); } rs=pst.executeQuery(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return rs; } public <T> int executeSql(String sql,List<T> values){ int affect=0; try { PreparedStatement pst=getConnection().prepareStatement(sql); System.out.println(sql); affect=executeSql(pst, values); } catch (SQLException e) { e.printStackTrace(); } return affect; } public ResultSet getRs(Statement st,String sql){ ResultSet rs=null; try { rs= st.executeQuery(sql); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return rs; } public String[] getColumnNames(ResultSet rs){ java.util.List<String> tittle=new ArrayList<String>(); try { ResultSetMetaData mt=rs.getMetaData(); for(int i=1;i<=mt.getColumnCount();i++){ tittle.add(mt.getColumnName(i)); } } catch (SQLException e) { e.printStackTrace(); } String[] column=new String[tittle.size()]; for(int i=0;i<column.length;i++) column[i]=tittle.get(i); return column; } public void printRs(ResultSet rs){ if(rs==null){ return; } try { String[] column=getColumnNames(rs); int columnCount=column.length; for(String s:column){ System.out.print(s+" "); } System.out.println(); int rowCount=0; while(rs.next()){ for(int i=1;i<=columnCount;i++){ System.out.print(rs.getObject(i)+" "); } System.out.println(); rowCount++; } if(rowCount==0) System.out.println("没有数据！"); } catch (SQLException e) { e.printStackTrace(); } } public void closeRs(ResultSet rs){ if(rs!=null){ try { rs.close(); rs=null; } catch (SQLException e) { e.printStackTrace(); } } } public void closeStatement(Statement st){ if(st!=null){ try { st.close(); st=null; } catch (SQLException e) { e.printStackTrace(); } } } public void closeCon(){ if(con!=null){ try { con.close(); con=null; } catch (SQLException e) { e.printStackTrace(); } } } }