jdbconnection.java

客户管理系统是一个典型的数据库开发应用程序

package com.tool;

import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.SQLException;
import java.sql.ResultSet;
import java.sql.Statement;

//这是一个工具类实现与数据库的连接
public class JDBConnection {

//String sd="com.microsoft.sqlserver.jdbc.SQLServerDriver";
	String sd="net.sourceforge.jtds.jdbc.Driver";
 // String sd = "sun.jdbc.odbc.JdbcOdbcDriver";
 //String sc = "jdbc:odbc:db_Client";
//String sc="jdbc:sqlserver://127.0.0.1:1433/db_Client";
String sc="jdbc:jtds:sqlserver://localhost:1433/db_Client;TDS=8.0";
 ResultSet rs = null;
 Connection conect = null;
 public JDBConnection() {
     try {
     Class.forName(sd).newInstance();

   }
   catch (java.lang.ClassNotFoundException e) {
     System.err.println(e.getMessage());
   } catch (InstantiationException e) {
	// TODO Auto-generated catch block
	e.printStackTrace();
} catch (IllegalAccessException e) {
	// TODO Auto-generated catch block
	e.printStackTrace();
} 
 }

 public ResultSet executeQuery(String sql) {
   try {
	   System.out.println(conect);
	   System.out.println("rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr");
     conect = DriverManager.getConnection(sc,"sa","");
     System.out.println(conect);
     Statement stmt = conect.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE,
                                             ResultSet.CONCUR_READ_ONLY);
     rs = stmt.executeQuery(sql);
     System.out.println("rrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr");
     System.out.println(rs);
   }
   catch (SQLException ex) {
     System.err.println(ex.getMessage());
   }
   return rs;
 }

 public int executeUpdate(String sql) {
   int result = 0;
   try {
     conect = DriverManager.getConnection(sc,"sa","");
     Statement stmt = conect.createStatement();
     result = stmt.executeUpdate(sql);
   }
   catch (SQLException er) {
     System.err.println(er.getMessage());
   }
   return result;
 }

 public void close() {
   try {
     if (conect != null) {
       conect.close();
     }
   }
   catch (Exception e) {
     System.out.println(e);
   }
 }


  //设置提交
  public void setAutoCommit(boolean flag) {
    try {
      conect.setAutoCommit(flag);
    }
    catch (Exception exception) {
      System.out.println("Exception in set autoCommit :" + exception.getMessage());
    }
  }

  //执行提交
  public void commit() {
    try {
      conect.commit();
    }
    catch (Exception exception) {
      System.out.println("Exception in commit :" + exception.getMessage());
    }
  }

  //执行回滚
  public void rollback() {
    try {
      conect.rollback();
    }
    catch (Exception exception) {
      System.out.println("Exception in rollback :" + exception.getMessage());
    }
  }

  //将sql语句中的？号转为相应的参数 ，其中参数为字符串型的
  public String editSqlCode(String sql, String str) {

    try {
      // 截取从0到第一个问号的字符串加参数str，然后在加上第一问号以后的字符串
      sql = sql.substring(0, sql.indexOf("?")) + str +
          sql.substring(sql.indexOf("?") + 1);
    }
    catch (Exception e) {
      System.out.println(e.getMessage());
    }
    return sql;
  }

  //将sql语句中的？号转为相应的参数 ，其中参数为长整型的
  public String editSqlCode(String sql, Integer str) {

    try {
      sql = sql.substring(0, sql.indexOf("?")) + str +
          sql.substring(sql.indexOf("?") + 1);

    }
    catch (Exception e) {
      System.out.println(e.getMessage());
    }
    return sql;
  }

  //将sql语句中的？号转为相应的参数 ，其中参数为整型的
  public String editSqlCode(String sql, int str) { //提取SQL语句，并把(int str)传出来的值来代替？

    try {
      sql = sql.substring(0, sql.indexOf("?")) + str +
          sql.substring(sql.indexOf("?") + 1);
    }
    catch (Exception e) {
      System.out.println(e.getMessage());
    }
    return sql;
  }
  //将sql语句中的？号转为相应的参数 ，其中参数为整型的
  public String editSqlCode(String sql, Float str) { //提取SQL语句，并把(Float str)传出来的值来代替？

    try {
      sql = sql.substring(0, sql.indexOf("?")) + str +
          sql.substring(sql.indexOf("?") + 1);
    }
    catch (Exception e) {
      System.out.println(e.getMessage());
    }
    return sql;
  }


}