Finding attributes in an object

[Tanya Ruttenberg]

I have an object called SearchCriteria with about 20 attributes, each one being a criteria via which one could search.

@Name("searchCriteria")
public class SearchCriteria {
	
	//Devices
	String name;
	
	//Offices
	String state;
	
	//DevInterfaces
	String peRouter;

	//SiteCodes
	String siteCode;
	
	//Rings
	String ring;
	
	//SiteTypes
	String siteType;
	
	//AssetTags
	String assetTag;

        etc. etc.

	// Getters and Setters
	
	
}

I need to build a db query based on any of these criteria. I'd like to programmatically loop through the object's attributes testing each one for null and then taking action on the ones that are not null. How do you programmatically loop through an object's attributes?

TDR

[Wouter Oet]

You could do this with reflection.
But I think you could come up with a better solution. Hibernate has a criteria class. You could look at that.

[Tanya Ruttenberg]

I can definitely do this using hibernate restrictions, but the difficulty is that these criteria come from up to 7 tables and in order to be able to use the restrictions I need to fetch join all 7 tables. I'm only displaying data from 2 of these tables so why do the huge fetch? Big waste of resources.

So I'm trying to come up with a different way of finding the objects.

[Ireneusz Kordal]

import java.lang.reflect.Field;

public class SearchCriteria {

	//Devices
	String name;

	//Offices
	String state;

	//DevInterfaces
	String peRouter;

	//SiteCodes
	String siteCode;

	//Rings
	String ring;

	//SiteTypes
	String siteType;

	//AssetTags
	String assetTag;

        //etc. etc.

	// Getters and Setters
        public static void main(String ...s) throws IllegalArgumentException, IllegalAccessException{
            SearchCriteria sc = new SearchCriteria();
            sc.ring = "ring";
            sc.siteCode = "site code";

            Class <?> c = sc.getClass();
            Field [] fields = c.getDeclaredFields();
            for(Field f: fields){
                f.setAccessible(true); // in case f is private or protected
                if(f.get(sc) != null){
                    System.out.println( f.getName() + "  =  " + f.get(sc).toString());
                }else{
                    System.out.println( f.getName() + "  is null ");
                }
            }
        }
}