Operating sublists efficiently

In my Java program, I need to operate on the sublists a of ArrayList or LinkedList often, like removing a sublist, comparing two sublists.

For ArrayList or LinkedList, I didn't find any good APIs to do these. My current implementation is as below. Basically, it takes an input like:

u1234 u1236 u1236 u2def u1236 u1236 u2def

and outputs the following:

u1234 ( ( u1236 ) * u2def ) *

Core function:

ArrayList toRegex(ArrayList tokenArray)
{
    /* check different length of continuous duplication */
    for(int len=1; len first = new ArrayList();
            ArrayList second = new ArrayList();
            for(int j=i; j tokenArray.size())
                    break;
                second.clear();
                for(int j=i+len; j<i+2*len; j++)
                    second.add(tokenArray.get(j));
            }

            if(match == true) {
                tokenArray.add(i, "(");
                tokenArray.add(i+1+len, ")");
                tokenArray.add(i+2+len, "*");
                i = i+3+len;
                match = false;
            }  
       }
    }

    return tokenArray;
}

Currently, the performance is not good. Could you find the bad design or inappropriate usage of data structures/APIs? What are the good common ways of operating sublists?

Yes, this doesn't look pretty. Consider converting the list to sets or using RegEx.

ArrayList A = new ArrayList();
A.add("Z");
A.add("Z");
A.add("C");
A.add("X");
A.add("Z");

Set set = new HashSet(A);

for(String temp:set)
    System.out.println(temp);

Sublists:

List subList = alist.subList(2, 4);

Use retainAll to get intersections:

listOne.retainAll(listTwo) ;  
boolean areEqualNotSamePosition = listeOne.size();

StackExchange Code Review Q#17788, answer score: 2