Java – Expressions in hibernate criteria

hibernatejava

Let's say I have a persistent class Item with a quantity field and a price field.
Is there a way to build a Criteria that calculates the sum of quantity*price?

Best Solution

I think you can also use an SQL projection. It should be something like:

session.createCriteria(Item.class) 
        .createAlias("item", "i") 
        .setProjection( Projections.projectionList() 
            .add( Projections.groupProperty("i.id") ) 
            .add( Projections.groupProperty("i.price") ) 
            .add( Projections.groupProperty("i.quantity") ) 
            .add( Projections.sqlProjection( 
                    "price * quantity as total", 
                    new String[] { "total" }, 
                    new Type[] { Hibernate.DOUBLE } 
                  ) 
            ) 
        );

Ori

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On Java 10+:

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Here's a generic-friendly version:

public class MapUtil {
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}

Best Solution

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