设备管理系统源代码
package com.DB;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement; import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class DBManager {
private final static String driver =
"com.microsoft.jdbc.sqlserver.SQLServerDriver";
private final static String url =
"jdbc:microsoft:sqlserver://127.0.0.1:1433;DataBaseName=bbsDB";
private Connection conn;
private Statement st;
private ResultSet rs;
/**
* 创建连接
* @return
*/
public Connection getConnection(){
if(conn==null){
try {
Class.forName(driver);
conn = DriverManager.getConnection(url,"sa","root");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return conn;
}
/**
* 创建 statement
*/
public Statement getStatement(){
if(st==null){
try {
st = conn.createStatement();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return st;
}
/**
* 执行更新操作
*/
public int update(String sql){
System.out.println(">>>>>>>>===="+sql);
getConnection();
int rows=0;
st=getStatement();
try {
rows = st.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
}finally{
closeAll();
}
return rows;
}
/**
* 使用预处理
*/
public int update(String sql,String data[]){
System.out.println(">>>>==="+sql);
getConnection();
try {
int index = 0;
PreparedStatement pst = conn.prepareStatement(sql);
for (int i = 0; i < data.length; i++) {
pst.setString(++index, data[i]);
}
return pst.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
}finally{
closeAll();
}
return 0;
}
/**
* 执行查询操作
*/
public ResultSet getQuery(String sql){
System.out.println(">>>>>>>>===="+sql);
getConnection();
st = getStatement();
try {
rs = st.executeQuery(sql);
} catch (SQLException e) {
e.printStackTrace();
}
return rs;
}
/**
* 执行关闭
*/
public void closeAll(){
if(rs!=null){
try {
rs.close();
rs = null;
} catch (SQLException e) {
e.printStackTrace();
}
}
if(st!=null){
try {
st.close();
st = null;
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn!=null){
try {
conn.close();
conn = null;
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}