java哈夫曼树实例代码

package boom;
 
import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Queue;
 
class Node<T> implements Comparable<Node<T>>{
  private T data;
  private int weight;
  private Node<T> left;
  private Node<T> right;
   
  public Node (T data,int weight){
    this.data = data;
    this.weight = weight;
  }
   
  public int compareTo(Node<T> other) {
    if(this.weight > other.getWeight()){
      return -1;
    }if(this.weight < other.getWeight()){
      return 1;
    }
    return 0;
  }
 
  public T getData() {
    return data;
  }
 
  public void setData(T data) {
    this.data = data;
  }
 
  public int getWeight() {
    return weight;
  }
 
  public void setWeight(int weight) {
    this.weight = weight;
  }
 
  public Node<T> getLeft() {
    return left;
  }
 
  public void setLeft(Node<T> left) {
    this.left = left;
  }
 
  public Node<T> getRight() {
    return right;
  }
 
  public void setRight(Node<T> right) {
    this.right = right;
  }  
   
  public String toString(){ 
    return "data:"+this.data+";weight:"+this.weight; 
  } 
}
 
public class huffuman<T> {
  static <T> Node<T> create(List<Node<T>> nodes){
    while(nodes.size()>1){
      Collections.sort(nodes); 
      Node<T> left = nodes.get(nodes.size()-1);
      Node<T> right = nodes.get(nodes.size()-2);
      Node<T> parent = new Node<T>(null,left.getWeight()+right.getWeight());
      parent.setRight(right);
      parent.setLeft(left);
      nodes.remove(left);
      nodes.remove(right);
      nodes.add(parent);
    }
    return nodes.get(0);  
  }
  static<T> List<Node<T>> breadth(Node<T> root){
    List<Node<T>> list = new ArrayList<Node<T>>();
    Queue<Node<T>> queue = new ArrayDeque<Node<T>>();
    queue.offer(root);
    while(queue.size()>0){
      Node<T> out = queue.poll();
      list.add(out);
      if(out.getLeft()!=null){
        queue.offer(out.getLeft());
      }
      if(out.getRight()!=null){
        queue.offer(out.getRight());
      }
    }
    return list;
  }
  public static void main(String[] args) { 
    // TODO Auto-generated method stub 
    List<Node<String>> list = new ArrayList<Node<String>>(); 
    list.add(new Node<String>("a",7)); 
    list.add(new Node<String>("b",5)); 
    list.add(new Node<String>("c",4)); 
    list.add(new Node<String>("d",2)); 
      
    Node<String> root =huffuman.create(list); 
    System.out.println(huffuman.breadth(root)); 
//   System.out.println(list); 
  }
    
   
}