CareerCup

Please provide the code , if anybody knows it..

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.HashMap;
import java.util.stream.Collectors;
import java.util.stream.Stream;


public class App
{
    public interface Component {
        Component merge(Component other);
    }

    public class Scanner {
        Component fromString(String str) {
            Component c = null;
            if(str.length() != 0) {
                Character key = str.charAt(0);
                String sub = str.substring(2, str.length());
                if (str.charAt(1) == '>') {
                    c = new Composite(key, fromString(sub));
                } else if (str.charAt(1) == '=') {
                    c = new Leaf(key, Integer.parseInt(sub));
                } else { // TODO : invalid operator, raise exception
                }
            }
            return c;
        }
    }

    public class Leaf extends HashMap<Character, Object> implements Component {
        public Leaf(Character k, Integer v) {
            put(k,v);
        }
        public Component merge(Component other) {
            if (other instanceof Leaf) {
                Leaf o = (Leaf)other;
                for (Character key : o.keySet()) {
                    if(keySet().contains(key)) {
                        if (get(key) instanceof List) {
                            ((List)get(key)).add(o.get(key));
                        } else {
                            List<Object> l = new ArrayList<Object>();
                            l.add(get(key));
                            l.add(o.get(key));
                            put(key, l);
                        }
                    } else {
                        put(key, o.get(key));
                    }
                }
            }
            return this;
        }
        public String toString() {
            String s = "{";
            for (Map.Entry<Character, Object> entry : entrySet()) {
                s+= "'"+entry.getKey()+"'"+":"+entry.getValue()+", ";
            }
            return s+"}";
        }
    }


    public class Composite extends HashMap<Character, Object> implements Component {
        public Composite(Character k, Object v) {
            put(k,v);
        }
        public Component merge(Component other) {
            return (Composite)deepMerge(this, (Map)other);
        }

        private Map deepMerge(Map l, Map r) {
            for (Object key : r.keySet()) {
                if (l.keySet().contains(key)) {
                    if (l.get(key) instanceof Map && r.get(key) instanceof Map) {
                        Map lChild = (Map)l.get(key);
                        Map rChild = (Map)r.get(key);
                        l.put(key, deepMerge(lChild, rChild));
                    } else if (l.get(key) instanceof List) {
                        List lChild = (List)l.get(key);
                        lChild.add(r.get(key));
                    } else {
                        List<Object> li = new ArrayList<Object>();
                        li.add(l.get(key));
                        li.add(r.get(key));
                        l.put(key, li);
                    }
                } else {
                    l.put(key, r.get(key));
                }
            }
            return l;
        }

        public String toString() {
            String s = "{";
            for (Map.Entry<Character, Object> entry : entrySet()) {
                s+= "'"+entry.getKey()+"'"+":"+entry.getValue()+", ";
            }
            return s+"}";
        }
    }

    public static void main( String[] args ) throws java.io.IOException {
        App s = new App();
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String line;
        App.Component c = null;
        while(true) {
            line = br.readLine();
            if (line == null || line.isEmpty()) {
                break;
            }
            if (c == null) {
                c = s.new Scanner().fromString(line);
            } else {
                c.merge(s.new Scanner().fromString(line));
            }
        }
        System.out.println(c);
    }
}

output:

SUJITs-MacBook-Pro:com.packt.samples.archetype sujitroutray$ java -jar target/com.packt.samples.archetype-1.0.0.jar
a>b=1
a>b=2
a>c>e=3
a>c>f=4
b>a=5
a>b>c=5
b=7
a>b>c>d=99
a>b=99

{'a':{'b':[1, 2, {'c':5, }, {'c':{'d':99, }, }, 99], 'c':{'e':3, 'f':4, }, }, 'b':[{'a':5, }, 7], }