You can create csv files with object and field list then use below java codes to generate xml file.

import java.io.File;
import java.io.FileReader;
import java.io.IOException;

import java.util.ArrayList;
import java.util.List;

import org.apache.commons.io.FileUtils;

import au.com.bytecode.opencsv.CSVReader;

public class GenerateDestructiveXML {	
	public static void main(String[] args) throws IOException {
		GenerateDestructiveXML obj=new GenerateDestructiveXML();
		obj.generateXML();
	}
	public void generateXML() throws IOException{
        Object lstColumnName[]={"Object Name","Field Name","Count"};
        List<ObjectList> lstObjectList = new ArrayList<ObjectList>();
        lstObjectList = readDataFromCSV("E:\\CustomObject_Fields_ComponentCount.csv", lstColumnName);//Use your path here
        
        if(lstObjectList.size()>0)
        {
        	String strXML = "";
        	strXML = "<?xml version='1.0' encoding='UTF-8'?>";
        	strXML += "\n<Package xmlns='http://soap.sforce.com/2006/04/metadata'>";
        	strXML += "\n\t<fullName>codepkg</fullName>";
        	for(ObjectList obj:lstObjectList)
        	{
        		if(obj.count != null && obj.count<=0)
        		{
        			strXML += "\n\t<types>";
        			strXML += "\n\t\t<members>" + obj.name.trim() + "." + obj.field.trim() + "</members>";
        			strXML += "\n\t\t<name>CustomField</name>";
        			strXML += "\n\t</types>";
        		}
        	}
        	strXML += "\n\t<version>17.0</version>";
        	strXML += "\n\t</Package>";
        	FileUtils.writeStringToFile(new File("E:\\DestructiveChanges.xml"), strXML);//Use your path here
        }
		
	}
	public class ObjectList{
		public String name;
		public String field;
		public Integer count;
	}
    public List<ObjectList> readDataFromCSV(String FileName,Object[] lstColumnName)
	{
		String parentId=null;
		ArrayList dt=new ArrayList();
		CSVReader reader =null;
		List<ObjectList> lstObjectList = new ArrayList<ObjectList>();
		try
		{
			reader = new CSVReader(new FileReader(FileName));
			String[] nextLine;
			int index = 0;
			int parentIndex = -1;
			boolean firstline = false;
			while ((nextLine = reader.readNext()) != null)
			{
				Object[] row = new Object[lstColumnName.length];
				if(firstline == false)
				{
					for (int i = 0; i < nextLine.length; i++)
					{
						System.out.println("nextLineindex[i]::::" + nextLine[i]);
					}
					firstline = true;
				}
				else
				{
					//System.out.println("index::::" + index);
					ObjectList obj = new ObjectList();
					boolean addRow = false;
					for (int i = 0; i < lstColumnName.length; i++)
					{
						
						if(lstColumnName[i].toString().trim().equalsIgnoreCase("Object Name")){
							obj.name = nextLine[i].trim();
							if(obj.name != null) addRow = true;
							System.out.println("@@@ Object Name: " + obj.name);
						}
						if(lstColumnName[i].toString().trim().equalsIgnoreCase("Field Name")){
							obj.field = nextLine[i].trim();
							System.out.println("@@@ field Name: " + obj.field);
						}
						if(lstColumnName[i].toString().trim().equalsIgnoreCase("Count")){
							obj.count = Integer.valueOf(nextLine[i].trim());
							System.out.println("@@@ count: " + obj.count);
						}
						System.out.println(lstColumnName[i] + "::::" + nextLine[i]);
						row[i] = nextLine[i];
					}
					if(addRow) lstObjectList.add(obj);
					dt.add(row);

				}//end of else

			}//end of while
		}
		catch (Exception e)
		{
			System.out.println("Exception: in read csv"+e);
		}
		finally
		{
			try{
				reader.close();
				reader=null;
			}catch(Exception e){
				System.out.println("Exception "+e);
			}
		}

	return lstObjectList;
	}
}