java-tutorials/protobuffer/src/test/java/com/baeldung/protobuf/ProtobufUnitTest.java

package com.baeldung.protobuf;


import org.junit.After;
import org.junit.Test;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Random;

import static org.junit.Assert.assertEquals;

public class ProtobufUnitTest {
    private final String filePath = "address_book";

    @After
    public void cleanup() throws IOException {
        Files.deleteIfExists(Paths.get(filePath));
    }

    @Test
    public void givenGeneratedProtobufClass_whenCreateClass_thenShouldCreateJavaInstance() {
        //when
        String email = "j@baeldung.com";
        int id = new Random().nextInt();
        String name = "Michael Program";
        String number = "01234567890";
        AddressBookProtos.Person person =
                AddressBookProtos.Person.newBuilder()
                        .setId(id)
                        .setName(name)
                        .setEmail(email)
                        .addNumbers(number)
                        .build();
        //then
        assertEquals(person.getEmail(), email);
        assertEquals(person.getId(), id);
        assertEquals(person.getName(), name);
        assertEquals(person.getNumbers(0), number);
    }


    @Test
    public void givenAddressBookWithOnePerson_whenSaveAsAFile_shouldLoadFromFileToJavaClass() throws IOException {
        //given
        String email = "j@baeldung.com";
        int id = new Random().nextInt();
        String name = "Michael Program";
        String number = "01234567890";
        AddressBookProtos.Person person =
                AddressBookProtos.Person.newBuilder()
                        .setId(id)
                        .setName(name)
                        .setEmail(email)
                        .addNumbers(number)
                        .build();

        //when
        AddressBookProtos.AddressBook addressBook = AddressBookProtos.AddressBook.newBuilder().addPeople(person).build();
        FileOutputStream fos = new FileOutputStream(filePath);
        addressBook.writeTo(fos);
        fos.close();

        //then
        FileInputStream fis = new FileInputStream(filePath);
        AddressBookProtos.AddressBook deserialized =
                AddressBookProtos.AddressBook.newBuilder().mergeFrom(fis).build();
        fis.close();
        assertEquals(deserialized.getPeople(0).getEmail(), email);
        assertEquals(deserialized.getPeople(0).getId(), id);
        assertEquals(deserialized.getPeople(0).getName(), name);
        assertEquals(deserialized.getPeople(0).getNumbers(0), number);


    }
}