A builder I made for apache's velocity template

VelocityTemplateBuilder.java

import lombok.Getter;
import lombok.Setter;
import spark.ModelAndView;
import spark.template.velocity.VelocityTemplateEngine;

import java.util.HashMap;

@Getter
@Setter
public class VelocityTemplateBuilder {
    private HashMap<String,Object> model = new HashMap<>();
    private String viewName;
    public VelocityTemplateBuilder(String viewName){
        this.viewName = viewName;
        if (!this.viewName.endsWith(".vm"))
            this.viewName = viewName + ".vm";
    }
    public VelocityTemplateBuilder addEntry(String key,Object value){
        model.put(key,value);
        return this;
    }
    public String build(){
        return new VelocityTemplateEngine().render(new ModelAndView(model,viewName));
    }
}