package lojadepc;
import java.sql.Connection;
import java.sql.Statement;
import javax.swing.JOptionPane;

public class Comprador {


    public String nome;
    public String endereco;
    public String telefone;

    Statement sentence = null;
    Connection conexao = null;

public Comprador (String nome, String endereco, String telefone) {
    this.nome = nome;
    this.endereco = endereco;
    this.telefone = telefone;
 }

public String getNome(){
   return nome;
}

public String getEndereco(){
    return endereco;
}

public String getTelefone(){
    return telefone;
}

public void cadastraTransacao(Connection con){
conexao = con;
        try
        {
            String query;

            {
                {
                query = "INSERT INTO Transacao (nome, endereco, telefone) "
                    + "VALUES('" + this.nome + "', '" + this.endereco + "', '" + this.telefone + "')";
            }
            }


            System.out.println(query);
            sentence = conexao.createStatement();
            sentence.executeUpdate(query);
            JOptionPane.showMessageDialog(null, "Compra cadrastada!");
        }
        catch(Exception e)
        {
            JOptionPane.showMessageDialog(null, "Falha no cadastro.");
            System.out.println("Erro: " + e.toString());
        }
}

}

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package lojadepc;

import java.sql.*;
import javax.swing.JOptionPane;

public class ConnectionDataBase
{
    Connection conexao;
    Statement sentenca;

    public Connection connect()
    {
        String url = "jdbc:postgresql://localhost:5433/postgres";
        String usuario = "root";
        String senha = "";

        try
        {
            Class.forName("org.postgresql.Driver");
            conexao = DriverManager.getConnection(url, usuario, senha);
            JOptionPane.showMessageDialog(null, "Conexao realizada com sucesso!");
            sentenca = conexao.createStatement();
            sentenca.execute("SET search_path TO transacao;");
        }
        catch(ClassNotFoundException e)
        {
            JOptionPane.showMessageDialog(null, "Erro Classe:" + e.getMessage());
        }
        catch(SQLException e)
        {
            JOptionPane.showMessageDialog(null, "Erro SQL:" + e.getMessage());
        }
        return conexao;
    }
}