Eclipse to MySQL JDBC Add without run time errors.
1:Download Mysql-connector-java-8.0.11.jar file
2:create folder inside your project and inside to copy Mysql-connector-java-8.0.11.jar file.
3:Right click your Project and go to properties.
4:Then click java-build-path and select Libraries.
5:Then selct Classpath and after click Add-External-Jars and select that Mysql-connector-java-8.0.11.jar file
6:pply and close click
7:If maven project ..open pom.xml file and add dependancy.
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.11</version>
</dependency>
8:maven update dependancy Click
9: Save All
10:Finish
Database Java class
package com.savindu.databasePkg;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Database {
private static final String urldb = “jdbc:mysql://localhost:3306/hospital”;
private static final String usernamedb = “root”;
private static final String passworddb = “”;
public Connection conn = null;
public PreparedStatement pStatment;
public ResultSet resultSet = null;
public Database() throws SQLException {
try {
conn = (Connection) DriverManager.getConnection(urldb, usernamedb, passworddb);
} catch (SQLException ex) {
System.out.println(ex);
}
}
public ResultSet read(String selectQuery) {
try {
pStatment = (PreparedStatement) conn.prepareStatement(selectQuery);
resultSet = pStatment.executeQuery();
} catch (SQLException ex) {
System.out.println(ex);
resultSet = null;
}
return resultSet;
}
public ResultSet search(String selectQuery) {
try {
pStatment = (PreparedStatement) conn.prepareStatement(selectQuery);
resultSet = pStatment.executeQuery();
} catch (SQLException ex) {
System.out.println(ex);
resultSet = null;
}
return resultSet;
}
public boolean add(String insertQuery) {
boolean x = false;
try {
//new Database();
conn = (Connection) DriverManager.getConnection(urldb, usernamedb, passworddb);
pStatment = (PreparedStatement) conn.prepareStatement(insertQuery);
x = true;
} catch (SQLException ex) {
System.out.println(ex);
x = false;
}
return x;
}
public boolean update(String updateQuery) {
boolean x = false;
try {
pStatment = (PreparedStatement) conn.prepareStatement(updateQuery);
x = true;
} catch (SQLException ex) {
System.out.println(ex);
x = false;
}
return x;
}
public boolean delete(String deleteQuery) {
boolean x = false;
try {
pStatment = (PreparedStatement) conn.prepareStatement(deleteQuery);
x = true;
} catch (SQLException ex) {
System.out.println(ex);
x = false;
}
return x;
}
public boolean executeQuery() throws SQLException {
boolean x = false;
try {
if (pStatment.executeUpdate() == 1) {
x = true;
} else {
x = false;
}
} catch (SQLException e) {
e.printStackTrace();
}finally {
pStatment.close();
conn.close();
}
return x;
}
}
Use that java class methods.
Login java class
package com.savindu.databasePkg;
import java.sql.ResultSet;
import java.sql.SQLException;
public class Login extends Database {
public String ss =”savindu”;
public Login() throws SQLException {
super();
}
public boolean userValid(String username,String password) throws SQLException {
boolean res = false;
ResultSet resultSe = super.read(“SELECT `password` FROM `login` WHERE `username`=’”+username+”’”);
if (resultSet != null) {
while (resultSe.next()) {
if(resultSe.getString(“password”) == password) {
res = true;
}
}
}
super.conn.close();
return res;
}
public void read() throws SQLException {
new Database();
ResultSet resultSe = super.read(“SELECT * FROM `login`”);
if (resultSet != null) {
while (resultSe.next()) {
System.out.println(resultSe.getString(“username”));
}
}
super.conn.close();
}
public boolean add(String username, String password) throws SQLException {
super.add(“INSERT INTO `login` (`username`, `password`, `timestamp`) VALUES (?,?,?)”);
super.pStatment.setString(1, username);
super.pStatment.setString(2, password);
super.pStatment.setString(3, null);
return super.executeQuery();
// id:autoincrement int
}
public boolean update(String username, String password, int id) throws SQLException {
super.update(“UPDATE `login` SET `username`=?, `password`=?, WHERE id=?”);
super.pStatment.setString(1, username);
super.pStatment.setString(2, password);
super.pStatment.setString(3, username);
return super.executeQuery();
}
public boolean deletec(String username) throws SQLException {
String query = “DELETE FROM `login` WHERE `username`=?”;
super.pStatment.setString(1,username);
super.delete(query);
return super.executeQuery();
}
}
