How to prepare a Java object to be sent (with values)?

Question

I have to send a serialized Java object, I already have this method that receives an object and sends, my doubt is how to set the values in the object, my data are in the database, just I take the data of the database set in the object and send? I’ve never done that, so I have that question.

Answer 1

First thing you should do is ensure that your entity is implementing the Serializable interface of the java.io package.Serializable;

After that, you will set the values of your object and with it ready you will do the actual serialization, transforming it into a set of bytes.

This is an example of a Client class, being persisted and obtained:

import java.io.Serializable;
//A classe deve implementar Serializable

public class Cliente implements Serializable {
    private String nome;
    private char sexo;
    private String cpf;

    public Cliente(String nome, char sexo, String cpf) {
        super();
        this.nome = nome;
        this.sexo = sexo;
        this.cpf = cpf;
    }

    public String getCpf() {
        return cpf;
    }

    public void setCpf(String cpf) {
        this.cpf = cpf;
    }

    public String getNome() {
        return nome;
    }

    public void setNome(String nome) {
        this.nome = nome;
    }

    public char getSexo() {
        return sexo;
    }

    public void setSexo(char sexo) {
        this.sexo = sexo;
    }

    public String toString() {
        return this.nome + " / " + "Sexo: " + this.sexo + "\n" + "CPF: "
                + this.cpf;
    }

}

Below follows the main which will perform the writing and reading of objects in a file.

public class ExemploStream {

    public static void main(String[] args) {

        // Cria o objeto serializado
        Cliente cliente = new Cliente("Glaucio Guerra", 'M', "0000000001");

        try {
            //Gera o arquivo para armazenar o objeto
            FileOutputStream arquivoGrav =
                    new FileOutputStream("/Users/glaucio/Desktop/saida.dat");

            //Classe responsavel por inserir os objetos
            ObjectOutputStream objGravar = new ObjectOutputStream(arquivoGrav);

            //Grava o objeto cliente no arquivo
            objGravar.writeObject(cliente);
            objGravar.flush();
            objGravar.close();
            arquivoGrav.flush();
            arquivoGrav.close();
            System.out.println("Objeto gravado com sucesso!");

        } catch (Exception e) {
            e.printStackTrace();
        }

        System.out.println("Recuperando objeto: ");

        try {

            //Carrega o arquivo
            FileInputStream arquivoLeitura = new FileInputStreamc:/saida.dat ");

            //Classe responsavel por recuperar os objetos do arquivo
            ObjectInputStream objLeitura =
                    new ObjectInputStream(arquivoLeitura);

            System.out.println(objLeitura.readObject());

            objLeitura.close();

            arquivoLeitura.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Exit:

Successfully recorded object!

Retrieving object:

Glaucio Guerra / Sex: M

CPF: 0000000001