Could I serialize List data?

ex)
public class Column extends BaseModel{
public Column(String id) {
set("id",id);
}
public int getId() {
return get("id");
}
public void setId(int id) {
set("id", id);
}
}

public class Document extends BaseModel{
public Document(String id) {
set("id",id);
}
public int getId() {
return get("id");
}
public void setId(int id) {
set("id", id);
}
}

public class DocumentsAndLayout extends BaseModel{
public DocumentsAndLayout(List<Column> columns, List<Document> data) {
set("columns", columns);
set("data", data);
set("dataColumns", dataColumns);
}
}

public List<Document> getData() {
return get("data");
}

public List<Column> getColumns() {
return get("columns");
}

public void setColumns(List<Column> columns) {
set("columns", columns);
}

public void setData(List<Document> data) {
set("data", data);
}
}