Sequent.java

import java.util.ArrayList;
import java.lang.StringBuilder;
public class Sequent
{
    public ArrayList<Formula> lhs;
    public ArrayList<Formula> rhs;
    public Sequent()
    {
        lhs = new ArrayList<Formula>();
        rhs = new ArrayList<Formula>();
    }
    public Sequent(ArrayList<Formula> lhs, ArrayList<Formula> rhs)
    {
        this.lhs = lhs;
        this.rhs = rhs;
    }
    public Sequent(String s)
    {
        Sequent ans = Sequent.parse(s);
        this.lhs = ans.lhs;
        this.rhs = ans.rhs;
    }
    public Sequent deepCopy()
    {
        ArrayList<Formula> left = new ArrayList<>(), right = new ArrayList<>();
        for(Formula f: lhs)
        {
            left.add(f);
        }
        for(Formula f: rhs)
        {
            right.add(f);
        }
        return new Sequent(left, right);
    }
    public static Sequent parse(String s)
    {
        // look for substring "|-"
        // if not found append at beginning
        // split across "|-"
        // split rhs and lhs along ','
        // trim individual string for spaces
        // run formula.parse on each split string, add to arraylist
        String[] sParsed;
        Sequent sq = new Sequent();
        if(s.contains("|-"))
        {
            sParsed = s.split("\\|\\-");
        }
        else
        {
            sParsed = new String[2];
            sParsed[0] = "";
            sParsed[1] = s;
        }
        
        sParsed[0] = sParsed[0].trim();
        sParsed[1] = sParsed[1].trim();
        
        if(sParsed[0].length() == 0) sParsed[0] = "T";
        if(sParsed[1].length() == 0) sParsed[1] = "L";
        
        String[] lStr = sParsed[0].split(",");
        String[] rStr = sParsed[1].split(",");
        
        for(String i: lStr)
        {
            sq.lhs.add(new Formula(i));
        }
        for(String i: rStr)
        {
            sq.rhs.add(new Formula(i));
        }
        return sq;
    }
    public String toString()
    {
        StringBuilder sb = new StringBuilder();
        int i;
        try
        {
            sb.append(lhs.get(0).toString());
            for(i = 1; i < lhs.size(); i++)
            {
                sb.append(", ");
                sb.append(lhs.get(i));
            }
        }
        catch(Exception e) {}
        sb.append(" |- ");
        try
        {
            sb.append(rhs.get(0).toString());
            for(i = 1; i < rhs.size(); i++)
            {
                sb.append(", ");
                sb.append(rhs.get(i));
            }
        }
        catch(Exception e) {}
        return sb.toString();
    }
}