CompareObjects.java

package com.hygenics.comparator;

import java.util.Comparator;

public class CompareObjects<E> implements Comparator<E>{
	
	
	public CompareObjects(){
		
	}
	
	
	/**
	 * Compare two generic values
	 * if o is < co -> retvalue=-1
	 * else if o=co -> revalue=0
	 * else retvalue 1
	 * 
	 * Implements and overrides Comparator to avoid instantiating a new class for every arraylist object
	 * 
	 * @param o -compare
	 * @param co -compare to
	 * @return revalue - the integer value representing the result
	 */
	public int compare(Object o, Object co) {
		// TODO compare two objects of the same type
		
		int retvalue=-2;
	
		if(o instanceof java.lang.String & co instanceof java.lang.String){
	
			//compare strings
			String comp=(String) o;
			String compto=(String) co;
			
			int i=0;
			
			while(retvalue==-2 & i<comp.length())
			{
				if(i> (compto.length()-1) & i< (comp.length()-1))
				{
					retvalue=1;
				}
				else if(i>(comp.length()-1) & i < (compto.length()-1))
				{
					retvalue=-1;
				}
				else if(i>comp.length() & i>compto.length())
				{
					retvalue=0;
				}
				else if(comp.charAt(i)<compto.charAt(i)){
					retvalue=-1;
				}
				else if(comp.charAt(i)>compto.charAt(i))
				{
					retvalue=1;
				}
				
				i++;
			}

		}
		else{
				//compare numbers and characters
				if(o instanceof java.lang.Float){
					if((java.lang.Float) o == (java.lang.Float)co)
					{
						retvalue=0;
					}
					else if((java.lang.Float) o < (java.lang.Float) co){
						retvalue=-1;
					}
					else{
						retvalue=1;
					}
					
				}
				else if(o instanceof java.lang.Double & co instanceof java.lang.Double){

						if((java.lang.Float) o == (java.lang.Float)co)
						{
							retvalue=0;
						}
						else if((java.lang.Float) o < (java.lang.Float) co){
							retvalue=-1;
						}
						else{
							retvalue=1;
						}
				}
				else if(o instanceof java.lang.Character &  co instanceof java.lang.Character){
					
					if((java.lang.Character) o == (java.lang.Character)co){
						retvalue=0;
					}
					else if((java.lang.Character)o < (java.lang.Character)co){
						retvalue=-1;
					}
					else{
						retvalue=1;
					}
				}
				else if(o instanceof java.lang.Integer & co instanceof java.lang.Integer){
					
					if((java.lang.Integer) o ==(java.lang.Integer) co){
						retvalue=0;
					}
					else if((java.lang.Integer) o < (java.lang.Integer) co)
					{
						retvalue=-1;
					}
					else{
						retvalue=1;
					}
				}
			
		}
		
		return retvalue;
	}
}