I need the below two methods called COMPRESS and DECOMPRESS to return the items

Question

I need the below two methods called COMPRESS and DECOMPRESS to return the items indicated in their method headers.  If I have made an error anywhere else please let me know

import java.io.FileInputStream;
import java.util.*;


public class HuffmanTree {
    public HuffmanNode overallRoot;
    
    public HuffmanTree(Map<Character, Integer> counts) {
        PriorityQueue<HuffmanNode> pq = new PriorityQueue<HuffmanNode>();
        Set<Character> characters = counts.keySet();
        for (Character c : characters) {
          pq.add(new HuffmanNode(c, c.charValue()));
        }
        System.out.println(pq.toString());
    }
    
    public String printSideways() {
        return printSideways(overallRoot, 0);
    }
    
    private String printSideways(HuffmanNode root, int level) {
        String sideways = "";
        if (root != null) {
            printSideways(root.right, level + 1);
            for (int i = 0; i < level; i++) {
                sideways += ("    ");
            }
            sideways += (root.frequency);
            printSideways(root.left, level + 1);
        }
        return sideways;
    }

    public StringBuilder compress(FileInputStream inputFile) {
        // TODO Auto-generated method stub
        return null;
    }

    public String decompress(StringBuilder inputString) {
        // TODO Auto-generated method stub
        return null;
    }

}

Explanation / Answer

import java.util.*; import java.io.*; public class HuffmanTree { private HuffNode root; private ArrayList ListOfChars; public HuffmanTree(Map counts) { /* This constructor constructs the huffman tree and fills all the characters in an ArrayList */ if(counts==null) { throw new IllegalArgumentException(); } FillSet(counts); PriorityQueue q=new PriorityQueue(counts.size()); for(char c:counts.keySet()) { q.add(new HuffNode(c,counts.get(c))); } add(q); } public Map createEncodings() {//This method creates encodings for all characters Map map=new TreeMap(); for(int i=0;i1) { HuffNode temp1=q.remove(); HuffNode temp2=q.remove(); HuffNode total=new HuffNode(temp1.count+temp2.count); total.left=temp1; total.right=temp2; q.add(total); } root=q.remove(); } private class HuffNode implements Comparable { // Class for the HuffNode private static final char default_char='~'; private char c; private int count; private HuffNode left; private HuffNode right; // Constructor taking a character and an integer private HuffNode(char c,int count) { this.c=c; this.count=count; this.left=null; this.right=null; } // Constructor taking an integer private HuffNode(int count) { this.c=default_char; this.count=count; this.left=null; this.right=null; } public int compareTo(HuffNode node) { return this.count-node.count; } } }

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