@Override
    public final Class<? extends T> getType() {
        return mixin.getType();
    }
{@code DslExpression} is the base class for DSL expressions, but {@link SimpleExpression} is the base class
for scalar Expressions

@author tiwe
@param <T> expression type
querydsl-core/src/main/java/com/querydsl/core/types/dsl/DslExpression.java