CODEWITHSUNDEEP
spring
Goldbones
Goldbones

Reputation: 1457

Map String values to bean in Spring

Imagine that we have a bean like this:

@Data
class MyBean{

private String name:
private String age;
private String gender;
...
}

And Another bean with order variables

@Data
class Order{

private String orderVariable;
private String orderValue;


}

I have a List of Order

[ "mygender","M"], ["myname", "Louis"],["myage", 12]...
[ "mygender","F"], ["myage", 13], ["myname", "Anna"]...
[ "myname", "Peter"], ["myage", 14], ["mygender","M"]...

I need to map both:

List<MyBean> myBeanList = new ArrayList<>();

for(Order order: ordersList){
    MyBean myBean = new MyBean();
    if(order.getOrderVariable().equals("myname")){
      myBean.setname(order.orderValue());
    }
    else if(order.getOrderVariable().equals("mygender")){
      myBean.setGender(order.orderValue());
     }
    else if(order.getOrderVariable().equals("myage")){
      myBean.setAge(order.orderValue());
    }
...
}

The problem is I have more than 20 variables in MyBean, so this is not the cleanest way. How can I do this?

Upvotes: 0

Views: 301

Answers (1)

Ervin Szilagyi
Ervin Szilagyi

Reputation: 16775

What I suggest to do is create a hash map which maps each orderVariable to a BiConsumer. This consumer is basically holds lambdas to setter methods for every field from MyBean.

This will look as follows:

Map<String, BiConsumer<Order, MyBean>> dispatch = new HashMap<String, BiConsumer<Order, MyBean>>() {{
    put("myname", (order, myBean) -> myBean.setName(order.getOrderValue()));
    put("mygender", (order, myBean) -> myBean.setGender(order.getOrderValue()));
    put("myage", (order, myBean) -> myBean.setAge(order.getOrderValue()));
    // Add other consumers for other fields
 }};

for (Order order : orderList) {
    MyBean myBean = new MyBean();
    dispatch.getOrDefault(order.getOrderVariable(), (unusedOrder, unusedMyBean) -> {}).accept(order, myBean);
    // Do something with myBean
}

Another approach would be the usage of reflection, although usually I don't really recommend it, since it can be pretty fragile and error prone.

public static void main(String[] args) throws IllegalAccessException {
    for (Order order : orderList) {
        MyBean myBean = new MyBean();

        // Get all fields from MyBean
        Field[] fields = myBean.getClass().getDeclaredFields();
        for (Field field : fields) {
                
            // Check if field name is similar to the orderVariable value from order. 
            if (order.getOrderVariable().contains(field.getName())) {

                // Make field accessible to be editable by reflection.
                field.setAccessible(true);

                // set field value
                field.set(myBean, order.getOrderValue());

                // reset the accessibility of the field 
                field.setAccessible(false);
            }
        }
        // Do something here
    }
}

Upvotes: 1

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