servlet+jdbc+html+jquery+Mysql資料庫（基於MVC的簡單查詢系統）
阿新 • • 發佈：2018-12-25
/**
* 資料庫連線工具
* @author yaochi
*
*/
public class DBHelper {
private static final String url = "jdbc:mysql://192.168.1.11/db_test_01";
private static final String driver = "com.mysql.jdbc.Driver";
private static final String user = "root";
private static final String password = "lyc971705";
public Connection conn = null;
public PreparedStatement pst = null;
private static DBHelper dbHelper = new DBHelper();
private DBHelper() {
try {
Class.forName(driver);//指定連線型別
conn = DriverManager.getConnection(url, user, password);//獲取連線
} catch (Exception e) {
e.printStackTrace();
}
}
public static DBHelper getJdbc() {
if(dbHelper==null) {
dbHelper = new DBHelper();
}
return dbHelper;
}
/**
* 查詢
* @param sql
* @return
*/
public ResultSet getResultSet(String sql) {
Connection con = DBHelper.getJdbc().conn;
PreparedStatement pstmt;
ResultSet rs;
try {
pstmt = con.prepareStatement(sql);
rs = pstmt.executeQuery();
return rs;
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
/**
* 刪除
* @param sql
* @return
*/
public int delete(String sql) {
int i = 0;
PreparedStatement pstmt;
try {
pstmt = DBHelper.getJdbc().conn.prepareStatement(sql);
i = pstmt.executeUpdate();
System.out.println("刪除成功");
DBHelper.getJdbc().close();
} catch (SQLException e) {
e.printStackTrace();
}
return i;
}
public void close() {
try {
this.conn.close();
this.pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
* 資料庫連線工具
* @author yaochi
*
*/
public class DBHelper {
private static final String url = "jdbc:mysql://192.168.1.11/db_test_01";
private static final String driver = "com.mysql.jdbc.Driver";
private static final String user = "root";
private static final String password = "lyc971705";
public Connection conn = null;
public PreparedStatement pst = null;
private static DBHelper dbHelper = new DBHelper();
private DBHelper() {
try {
Class.forName(driver);//指定連線型別
conn = DriverManager.getConnection(url, user, password);//獲取連線
} catch (Exception e) {
e.printStackTrace();
}
}
public static DBHelper getJdbc() {
if(dbHelper==null) {
dbHelper = new DBHelper();
}
return dbHelper;
}
/**
* 查詢
* @param sql
* @return
*/
public ResultSet getResultSet(String sql) {
Connection con = DBHelper.getJdbc().conn;
PreparedStatement pstmt;
ResultSet rs;
try {
pstmt = con.prepareStatement(sql);
rs = pstmt.executeQuery();
return rs;
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
/**
* 刪除
* @param sql
* @return
*/
public int delete(String sql) {
int i = 0;
PreparedStatement pstmt;
try {
pstmt = DBHelper.getJdbc().conn.prepareStatement(sql);
i = pstmt.executeUpdate();
System.out.println("刪除成功");
DBHelper.getJdbc().close();
} catch (SQLException e) {
e.printStackTrace();
}
return i;
}
public void close() {
try {
this.conn.close();
this.pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}