sqlquery.java

Java_JDK数据库系统开发

package mypack;


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

import com.mysql.jdbc.ResultSet;
import com.mysql.jdbc.Statement;

public class SQLQuery {

	public static boolean validate(String username,String password) {
		boolean bool = false;
		try {
			Class.forName("org.gjt.mm.mysql.Driver");
		} catch (java.lang.ClassNotFoundException e){
			System.out.print("Class not found exception occur. Message is:");
			System.out.print(e.getMessage());
		}

		try {
			Statement stmt;
			ResultSet rs;
			String url = "jdbc:mysql://localhost:3306/test";
			String user = "root";
			String passwordOfDB = "root";
			Connection conn = null;
			try {
				conn = DriverManager.getConnection(url, user, passwordOfDB);
			} catch (Exception ex) {
				ex.printStackTrace();
			}

			stmt = (Statement) conn.createStatement();
			rs = (ResultSet) stmt.executeQuery("select * from userinfo where username = '" +username+"' and password = '" +password+ "'");

			if(rs.next()) {
				bool = true;
			}else{
				bool = false;
			}
		} catch (SQLException e) {

			System.out.print("SQL Exception occur. Message is:");
			System.out.print(e.getMessage());
		}
		return bool;
	}
	
	public static Userinfo userinfoQuery(String username){
		Userinfo ui = new Userinfo();
		try {
			Class.forName("org.gjt.mm.mysql.Driver");
		} catch (java.lang.ClassNotFoundException e){
			System.out.print("Class not found exception occur. Message is:");
			System.out.print(e.getMessage());
		}

		try {
			Statement stmt;
			ResultSet rs;
			String url = "jdbc:mysql://localhost:3306/test";
			String user = "root";
			String passwordOfDB = "root";
			Connection conn = null;
			try {
				conn = DriverManager.getConnection(url, user, passwordOfDB);
			} catch (Exception ex) {
				ex.printStackTrace();
			}

			stmt = (Statement) conn.createStatement();
			rs = (ResultSet) stmt.executeQuery("select * from userinfo where username = '" +username+"'");
			
			while(rs.next()) {
				ui.setName(rs.getString(2));
				ui.setAge(rs.getInt(4));
				ui.setGender(rs.getString(5));
				ui.setEmail(rs.getString(6));
			}
		} catch (SQLException e) {
			System.out.print("SQL Exception occur. Message is:");
			System.out.print(e.getMessage());
		}
		return ui;
	}
	
}