AndroidStringResources.class

package com.alexstyl.myapplication;

import android.content.res.Resources;
import android.support.annotation.StringRes;

class AndroidStringResources implements StringResources {

    private final Resources resources;

    AndroidStringResources(Resources resources) {
        this.resources = resources;
    }

    @Override
    public String getString(@StringRes int resId) {
        return resources.getString(resId);
    }
}

DisplayName.java

package com.alexstyl.myapplication;

import java.util.Collections;
import java.util.List;

public class DisplayName {

    private final List<String> firstname;
    private final String lastName;


    DisplayName(List<String> firstname, String lastName) {
        this.firstname = firstname;
        this.lastName = lastName;
    }

    public List<String> getFirstNames() {
        return firstname;
    }

    public String getLastName() {
        return lastName;
    }
}

DisplayNameFactory.java

package com.alexstyl.myapplication;

import java.util.ArrayList;
import java.util.Collections;

final class DisplayNameFactory {

    private final StringResources resources;

    DisplayNameFactory(StringResources resources) {
        this.resources = resources;
    }

    public DisplayName createFromName(String rawName) {
        if (rawName == null) {
            String lastName = resources.getString(R.string.anonymous);
            return new DisplayName(Collections.<String>emptyList(), lastName);
        }
        String[] nameParts = rawName.trim().split("\\W");
        if (nameParts.length == 1) {
            return new DisplayName(Collections.<String>emptyList(), nameParts[0]);
        }

        ArrayList<String> firstNames = new ArrayList<>();
        for (int i = 0; i < nameParts.length - 1; i++) {
            String namePart = nameParts[i];
            firstNames.add(namePart);

        }
        return new DisplayName(firstNames, nameParts[nameParts.length - 1]);
    }

}

DisplayNameFactoryTest.java

package com.alexstyl.myapplication;

import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.runners.MockitoJUnitRunner;

import static org.fest.assertions.api.Assertions.assertThat;

@RunWith(MockitoJUnitRunner.class)
public class DisplayNameFactoryTest {

    private DisplayNameFactory displayNameFactory;

    @Before
    public void setUp() {
        StringResources resources = new TestingResources();
        displayNameFactory = new DisplayNameFactory(resources);
    }

    @Test
    public void givenNull_thenDisplayNameIsAnonymous() {
        DisplayName displayName = displayNameFactory.createFromName(null);
        assertThat(displayName.getFirstNames()).isEmpty();
        assertThat(displayName.getLastName()).isEqualTo("Anonymous");
    }

    @Test
    public void givenLastNameOnly_thenDisplayNameOnlyContainsLastName() {
        DisplayName displayName = displayNameFactory.createFromName(" Styl");
        assertThat(displayName.getLastName()).isEqualTo("Styl");
        assertThat(displayName.getFirstNames()).isEmpty();
    }

    @Test
    public void givenFirstNameAndLastName_thenDisplaynameContainsBothFirstNameAndLastName() {
        DisplayName displayName = displayNameFactory.createFromName("Alex Styl");
        assertThat(displayName.getFirstNames().get(0)).isEqualTo("Alex");
        assertThat(displayName.getLastName()).isEqualTo("Styl");
    }

    @Test
    public void namesSplitByColumn() {
        DisplayName displayName = displayNameFactory.createFromName("Vaso-Petra Papaxaralampou");
        assertThat(displayName.getFirstNames()).contains("Vaso");
        assertThat(displayName.getFirstNames()).contains("Petra");
        assertThat(displayName.getLastName()).contains("Papaxaralampou");
    }
}

StringResources.java

package com.alexstyl.myapplication;

import android.support.annotation.StringRes;

interface StringResources {
    String getString(@StringRes int resId);
}

TestingResources.java

package com.alexstyl.myapplication;

import android.support.annotation.StringRes;

class TestingResources implements StringResources {

    @Override
    public String getString(@StringRes int resId) {
        if (resId == R.string.anonymous) {
            return "Anonymous";
        }
        throw new IllegalArgumentException("Unsupported string");
    }
}