Populating Lists with harcoded data
So you need to separate the construction of that class from the class itself? This is the Factory Pattern.

Data class

Boil down to your DTO to ... well the data.

public class MassiveDTO {
    private final List&lt;String&gt; company;
    private final List&lt;String&gt; partners;
    private final List&lt;String&gt; biodata;

  /**
   * @see MassiveDTOBuilder
   */
  MassiveDTO(List&lt;String&gt; company, List&lt;String&gt; partners, List&lt;String&gt; biodata) {
    this.company = company;
    this.partners = partners;
    this.biodata = biodata;
  }
   ... getters only
}


Factory Pattern

Then have a second class, MassiveDTOFactory, that calls that constructor with suitable fixed values.

public class MassiveDTOFactory {
  public static MassiveDTO create() {
    return new MassiveDTO(
      List.of("X0788", "X0192"), // Here we use Java 9 immutable collections
      List.of("X0081"),
      List.of("X0913")
    );
  }
}


Fluent Builder Pattern

If you wish more flexibility on the values then a Fluent Builder is for you. Something like this: 

public class MassiveDTOBuilder {
  private List&lt;String&gt; companies = new ArrayList&lt;&gt;();
  private List&lt;String&gt; partners = new ArrayList&lt;&gt;();
  private List&lt;String&gt; biodata = new ArrayList&lt;&gt;();

  public static MassiveDTOBuilder massiveDto() {
    return new MassiveDTOBuilder();
  }

  private MassiveDTOBuilder() {
  }

  public MassiveDTOBuilder withCompany(String... items) {
    for (String i : items) {
      companies.add(i);
    }
    return this;
  }

  public MassiveDTOBuilder withPartner(String... items) {
    for (String i : items) {
      partners.add(i);
    }
    return this;
  }

  public MassiveDTOBuilder withBiodata(String... items) {
    for (String i : items) {
      biodata.add(i);
    }
    return this;
  }

  public MassiveDTO build() {
    return new MassiveDTO(
      Collections.unmodifiableList(companies),
      Collections.unmodifiableList(partners),
      Collections.unmodifiableList(biodata)
    );
  }
}


Which can used like:

MassiveDTO m = massiveDto()
  .withCompany("X0788", "X0192")
  .withPartner("X0081")
  .withBiodata("X0913")
  .build();