db.java

本人大二学习汇编语言程序设计时的全部源代码

package com.paradise.jdbc.util;

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 DB {

	static {
		try {
			Class.forName("com.mysql.jdbc.Driver");
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}
	
	private DB() {}
	
	public static Connection getConn() {
		Connection conn = null;
		try {
			conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/student?user=root&password=root");
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}
	
	public static Statement getStmt(Connection conn) {
		Statement stmt = null;
		try {
			stmt = conn.createStatement();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return stmt;
	}
	
	public static int executeUpdate(Connection conn, String sql) {
		int a = 0;
		try {
			a = conn.createStatement().executeUpdate(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return a;
	}
	
	public static boolean execute(Connection conn, String sql) {
		boolean flag = false;
		try {
			flag = conn.createStatement().execute(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return flag;
	}
	
	public static ResultSet executeQuery(Statement stmt, String sql) {
		ResultSet rs = null;
		try {
			rs = stmt.executeQuery(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return rs;
	}
	
	public static ResultSet executeQuery(Connection conn, String sql) {
		ResultSet rs = null;
		try {
			rs = conn.createStatement().executeQuery(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return rs;
	}
	
	public static PreparedStatement getPstmt(Connection conn, String sql) {
		PreparedStatement pstmt = null;
		try {
			pstmt = conn.prepareStatement(sql);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return pstmt;
	}
	
	public static void closeRS(ResultSet rs) {
		try {
			if(rs != null) {
				rs.close();
				rs = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	public static void closePstmt(PreparedStatement pstmt) {
		try {
			if(pstmt != null) {
				pstmt.close();
				pstmt = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	public static void closeStmt(Statement stmt) {
		try {
			if(stmt != null) {
				stmt.close();
				stmt = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	public static void closeConn(Connection conn) {
		try {
			if(conn != null) {
				conn.close();
				conn = null;
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

}