dboperate.java

通过jsp/servlet实现web打印

package bean;
import java.sql.*;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.sql.DataSource;
public class DBOperate {
	
	private Connection conn;
	public ResultSet result=null; 
	private static String jndi_name= "java:comp/env/jdbc/mandarin";
	public DBOperate(){
		
	}
	
	public static synchronized Connection getConnection()
	{
		Connection conn=null;
		DataSource ds = null;	
		Context ctx;
		try {
			ctx = new InitialContext();
			
			ds = (DataSource)ctx.lookup(jndi_name);
			conn = ds.getConnection();
		} catch (Exception e) {
			System.err.println(e.getMessage()+"连接失败！");
		}
		return conn;
	}
	
	/*获取查询结果*/
	public ResultSet getResult(String query_statement,String[] param) 
	{
	try
		{
		conn = getConnection();
		PreparedStatement select_stm=conn.prepareStatement(query_statement,java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);
		if (param!=null)
			for(int i=0;i<param.length;i++)
				select_stm.setString(i+1,param[i]);
				result=select_stm.executeQuery(); 
		}catch(Exception e){
				System.err.println(e.getMessage()+"没有获得结果集");
			}
				return result;
		}

	/*对数据库进行增加记录操作*/ 
	public void insertRecord(Connection conn,String query_statement,String[] param) throws SQLException,java.io.UnsupportedEncodingException
	{
	try{
		conn=getConnection();
		PreparedStatement insert_stm=conn.prepareStatement(query_statement);
		if (param!=null)
			for(int i=0;i<param.length;i++)
				insert_stm.setString(i+1,param[i]);
				insert_stm.executeUpdate();
				insert_stm.close();
				conn.commit();
	}
		catch(Exception e)
		{
			System.err.println(e.getMessage()+"插入数据失败");
			conn.rollback();
		}finally{
			closeConnection();
		} 
	}

	/*对数据记录进行更改操作*/ 
	public void updateRecord(String query_statement,String[] param) throws SQLException,java.io.UnsupportedEncodingException
	{
	try{
		PreparedStatement update_stm=conn.prepareStatement(query_statement);
		if (param!=null)
			for (int i=0;i<param.length;i++)
				update_stm.setString(i+1,param[i]);
				update_stm.executeUpdate();
				update_stm.close();
				conn.commit();
		}catch(Exception e){
			System.err.println(e.getMessage()+"更新数据失败！");
			conn.rollback();
		}finally{
			closeConnection();
		}
	}
	
	/*删除数据记录*/ 
	public void deleteRecord(String query_statement,String[] param) throws SQLException,java.io.UnsupportedEncodingException
	{
	try
	{
		conn=getConnection();
		PreparedStatement delete_stm=conn.prepareStatement(query_statement);
		if (param!=null)
			for (int i=0;i<param.length;i++)
				delete_stm.setString(i+1,param[i]);
				delete_stm.executeUpdate();
				delete_stm.close();
				conn.commit();
		}catch(Exception e){
			System.err.println(e.getMessage());
			conn.rollback();
		}finally{
			closeConnection();
		}
	} 
	
	
	public boolean setDataInfo(String sql) {
		try {
			conn =getConnection();
			Statement stmt = null;
			stmt = conn.createStatement();
			stmt.executeUpdate(sql);
			return true;
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		}finally{
			closeConnection();
		}
		
	}
	
	public ResultSet getDataInfo(String sql){
		Statement stmt = null;
		try{
				conn =getConnection();
				stmt = conn.createStatement();
				result = stmt.executeQuery(sql);
		}catch (Exception e){
			System.err.println(e.getMessage()+"没有获得结果集！");
		}
		return result;
	}
	
	public void closeConnection() {
		try {
			conn.close();
			conn=null;
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
}