编写程序,实现SerDes接口。完成对HuffmanTree类的序列化与反序列化。
import java.io.Serializable;
/**
* 序列化与反序列化方法接口,包含六个方法:
* byte[] serBin(T t) :将对象t序列化为字节数组
* String serText(T t) :将对象t序列化为一个字符串(可以先使用serBin序列化为字节数组,再用Base64编码为字符串)
* T des(byte[] bin) :将序列化后的字节数组反序列化为一个对象
* T des(String text) :将序列化后的字符串反序列化为一个对象
* serToFile :将对象序列化并写入磁盘文件
* desFromFile :将序列化后的对象从磁盘文件中读出
* @author chenruoyu
*
*/
public interface SerDes<T extends Serializable> {
/**
* 将对象t序列化为字节数组
* @param t
* @return 序列化后的字节数组
*/
public byte[] serBin(T t);
/**
* 将对象t序列化为一个字符串。
* 提示:可以先使用serBin方法将对象t序列化为字节数组,
* 再将字节数组用Base64编码为字符串
* @param t
* @return
*/
public String serTxt(T t);
/**
* 将序列化后的字节数组反序列化为一个对象
* @param bin
* @return
*/
public T des(byte[] bin);
/**
* 将序列化后的字符串反序列化为一个对象,
* 字符串应该是使用serText方法序列化得到的
* @param text
* @return
*/
public T des(String text);
/**
* 将对象序列化并写入磁盘文件。
* 提示:可以使用serBin将对象t序列化,
* 然后将序列化后的字节数组写入文件
* @param t
* @param path
* @param file
* @return
*/
public boolean serToFile(T t, String path, String file);
/**
* 将序列化后的对象从磁盘文件中读出。
* 提示:可以首先从磁盘中读出字节数组,
* 然后使用des方法将对象反序列化
* @param path
* @param file
* @return
*/
public T desFromFile(String path, String file);
}
``````java
public class HTNode implements Comparable<HTNode>{
public enum Code{
ZERO('0'), ONE('1');
private char code;
private Code(char c){
this.code = c;
}
public char getCode(){
return code;
}
}
/**
* 哈夫曼树的叶子结点数据
*/
private char data = 0;
/**
* 结点的编码,只有0和1两种可能
*/
private Code code = null;
public static final char zero = '0';
public static final char one = '1';
private double weight = 0;
private HTNode lchild = null;
private HTNode rchild = null;
private boolean isLeaf = false;
public int tempDength;
public HTNode() {
super();
}
public HTNode(double weight, HTNode lchild, HTNode rchild,
boolean isLeaf) {
super();
this.weight = weight;
this.lchild = lchild;
this.rchild = rchild;
this.isLeaf = isLeaf;
}
public char getData() {
return data;
}
public void setData(char data) {
this.data = data;
}
public double getWeight() {
return weight;
}
public void setWeight(double weight) {
this.weight = weight;
}
public HTNode getLchild() {
return lchild;
}
public void setLchild(HTNode lchild) {
this.lchild = lchild;
}
public HTNode getRchild() {
return rchild;
}
public void setRchild(HTNode rchild) {
this.rchild = rchild;
}
public boolean isLeaf() {
return isLeaf;
}
public void setLeaf(boolean isLeaf) {
this.isLeaf = isLeaf;
}
public Code getCode() {
return code;
}
public void setCode(Code code) {
this.code = code;
}
@Override
public int compareTo(HTNode o) {
if(this.weightreturn -1;
}else{
return 1;
}
}
public boolean equals(HTNode node){
if(this.weight != node.getWeight()){
return false;
}
else{
if(this.data != 0 && node.getData() != 0){
if(this.data == node.getData())
return true;
else
return false;
}
else if((this.data == 0 && node.getData() != 0) || (this.data != 0 && node.getData() == 0))
return false;
else{
if(this.getCode().equals(node.getCode())){
if(this.isLeaf == node.isLeaf()){
if(this.getLchild() != null && this.getRchild() != null &&node.getLchild() != null &&node.getLchild() != null){
if(this.getLchild().equals(node.getLchild()) && this.getRchild().equals(node.getRchild()))
return true;
else
return false;
}
else if((this.getLchild() == null && this.getRchild() != null) || (this.getLchild() != null && this.getRchild() == null)
|| (node.getLchild() == null &&node.getLchild() != null) || (node.getLchild() != null &&node.getLchild() == null))
return false;
else
return true;
}
else
return false;
}
else
return false;
}
}
}
}
``````java
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Queue;
import java.util.Stack;
import cn.edu.bistu.cs.HTNode.Code;
/**
* 哈夫曼树实现
*
*
*/
public class HuffmanTree {
/**
* 哈夫曼编码
*/
private Map code = null;
/**
* 生成的huffman树根结点
*/
private HTNode tree = null;
/**
* 根据初始的结点列表,建立哈夫曼树,
* 并生成哈夫曼编码,保存在当前类的code对象中,
* 生成的树根结点,被保存在当前类的tree对象中。
* 可以反复生成哈夫曼树,每次重新构建树,将更新编码
* @param nodes
* @return
*/
public HTNode buildTree(List nodes){
ArrayList nList = this.sortList(nodes);
while(nList.size() > 1){
if(nList.size() != 2){
HTNode p = nList.remove(0);
p.setCode(Code.ONE);
HTNode q = nList.remove(0);
q.setCode(Code.ZERO);
HTNode newNode = new HTNode(p.getWeight() + q.getWeight(), p, q, false);
nList.add(newNode);
nList = this.sortList(nList);
}
else{
HTNode p = nList.remove(0);
p.setCode(Code.ONE);
HTNode q = nList.remove(0);
q.setCode(Code.ZERO);
this.tree = new HTNode(p.getWeight() + q.getWeight(), p, q, false);
}
}
this.dength();
this.getCode();
return this.tree;
}
// 对结点列表排序
public ArrayList sortList(List nodes){
ArrayList nList = (ArrayList)nodes;
for(int i = 0; i < nList.size(); i++){
for(int j = i; j < nList.size(); j++){
if(nList.get(i).compareTo(nList.get(j)) == 1){
HTNode temp = nList.get(i);
nList.set(i, nList.get(j));
nList.set(j, temp);
}
}
}
return nList;
}
// 更新树各结点的深度
public void dength(){
Queue que = new LinkedList();
que.add(this.tree);
this.tree.tempDength = 1;
while(que.size() > 0){
HTNode p = que.poll();
if(p.getLchild() != null){
p.getLchild().tempDength = p.tempDength + 1;
que.add(p.getLchild());
}
if(p.getRchild() != null){
p.getRchild().tempDength = p.tempDength + 1;
que.add(p.getRchild());
}
}
}
/**
* 根据已建立的哈夫曼树根结点,生成对应的字符编码,
* 字符编码应为0,1字符串
* @param tree
* @return
*/
public static Map getCode(HTNode tree){
//TODO
Stack sList = new Stack();
Map codeList = new HashMap();
int temp = 1;
String codes = "";
sList.push(tree);
while(!sList.isEmpty()){
HTNode p = sList.pop();
if(temp > p.tempDength){
codes = codes.substring(0, codes.length() - (temp - p.tempDength));
}
temp = p.tempDength;
if(p.getRchild() != null)
sList.push(p.getRchild());
if(p.getLchild() != null)
sList.push(p.getLchild());
if(p.getCode() != null){
if(p.isLeaf()){
codeList.put(p.getData(), codes + p.getCode().getCode());
}
else
codes += p.getCode().getCode();
}
}
return codeList;
}
/**
* 获取已建立的哈夫曼树生成的字符编码,
* 字符编码应为0,1字符串
* @return
*/
public Map getCode(){
this.code = HuffmanTree.getCode(this.tree);
return this.code;
}
/**
* 统计字符串中字符出现的频率
* @param text
* @return
*/
public static Map computeCharCount(String text){
//TODO
Map hMap = new HashMap();
for(int i = 0; i < text.length(); i++){
char temp = text.charAt(i);
if(hMap.containsKey(temp)){
hMap.replace(temp, hMap.get(temp) + 1);
}
else{
hMap.put(temp, 1);
}
}
return hMap;
}
/**
* 使用当前类训练好的huffman编码来对文本进行编码
* @return
*/
public String encode(String text){
//TODO
return encode(text, this.code);
}
/**
* 使用指定的huffman编码来对文本进行编码
* @return
*/
public static String encode(String text, Map code){
//TODO
Map hMap = (HashMap)code;
if(code == null)
return null;
String result = "";
for(int i = 0; i < text.length(); i++){
char p = text.charAt(i);
result += hMap.get(p);
}
return result;
}
// 通过编码表得到解码表
public static Map disencode(Map code){
Map discode = new HashMap();
HashMap Hcode = (HashMap) code;
for(Entry en : Hcode.entrySet()){
discode.put(en.getValue(), en.getKey());
}
return discode;
}
/**
* 使用当前类中训练好的huffman编码,
* 对编码后的文本进行解码
* @param text
* @return
*/
public String decode(String text){
//TODO
return decode(text, this.tree);
}
public HTNode getTree() {
return tree;
}
/**
* 使用预先建立好的huffman树,
* 对编码后的文本进行解码
* @param text
* @return
*/
public String decode(String text, HTNode tree){
//TODO
if(tree == null || text == null)
return null;
HashMap code = (HashMap)getCode(tree);
HashMap discode = (HashMap)disencode(code);
String result = "";
String temp = "";
for(int i = 0; i < text.length(); i++){
temp += text.charAt(i);
if(discode.containsKey(temp)){
result += discode.get(temp);
temp = "";
}
}
return result;
}
public static void main(String[] args){
HuffmanTree htree = new HuffmanTree();
//首先对字符串中的字符出现次数进行统计
String data = "In computer science and information theory, "
+ "a Huffman code is a particular type of optimal prefix code that is commonly used for lossless data compression. "
+ "The process of finding and/or using such a code proceeds by means of Huffman coding, "
+ "an algorithm developed by David A. Huffman while he was a Ph.D. student at MIT, and published in the 1952 paper "
+ "\"A Method for the Construction of Minimum-Redundancy Codes\".[1] "
+ "The output from Huffman's algorithm can be viewed as a variable-length code table for encoding a source symbol "
+ "(such as a character in a file). The algorithm derives this table from the estimated probability or frequency of occurrence"
+ " (weight) for each possible value of the source symbol. As in other entropy encoding methods, more common symbols are generally "
+ "represented using fewer bits than less common symbols. Huffman's method can be efficiently implemented, "
+ "finding a code in linear time to the number of input weights if these weights are sorted.[2] However, "
+ "although optimal among methods encoding symbols separately, Huffman coding is not always optimal among all compression methods.";
Map chars = HuffmanTree.computeCharCount(data);
ArrayList nodes = new ArrayList<>();
for(Character c : chars.keySet()){
HTNode node = new HTNode();
node.setData(c);
node.setWeight(chars.get(c));
node.setLchild(null);
node.setRchild(null);
node.setLeaf(true);
nodes.add(node);
}
ArrayList nodeList = htree.sortList(nodes);
for(int i = 0; i < nodeList.size(); i++){
System.out.println(nodeList.get(i).getData()+ "" + nodeList.get(i).getWeight());
}
HTNode tree = htree.buildTree(nodes);
Map code = HuffmanTree.getCode(tree);
for(Character c : code.keySet()){
System.out.println("字符'"+c+"'的哈夫曼编码:"+code.get(c));
}
String text = "In computer science and information theory";
String coded = htree.encode(text);
System.out.println("字符串:In computer science and information theory");
System.out.println("被编码为:"+coded);
String oriText = htree.decode(coded);
System.out.println("编码:"+coded);
System.out.println("被解码为:"+oriText);
System.out.println(oriText.equals(text));
}
}
表示哈夫曼树的节点,包含两个属性:权值和左右子节点。节点类可以实现 Serializable 接口,表示该类可以序列化和反序列化。
import java.io.Serializable;
public class HuffmanNode implements Serializable {
private int weight;
private HuffmanNode leftChild;
private HuffmanNode rightChild;
public HuffmanNode(int weight) {
this.weight = weight;
}
public void setLeftChild(HuffmanNode leftChild) {
this.leftChild = leftChild;
}
public void setRightChild(HuffmanNode rightChild) {
this.rightChild = rightChild;
}
// getter and setter methods omitted for brevity
}
表示哈夫曼树,包含一个根节点属性。HuffmanTree 类同样可以实现 Serializable 接口。
public class HuffmanTree implements Serializable {
private HuffmanNode root;
public void setRoot(HuffmanNode root) {
this.root = root;
}
// getter and setter methods omitted for brevity
}
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
public class HuffmanSerDes {
public static byte[] serialize(HuffmanTree tree) throws IOException {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(tree);
oos.flush();
byte[] bytes = bos.toByteArray();
oos.close();
bos.close();
return bytes;
}
public static HuffmanTree deserialize(byte[] bytes) throws IOException, ClassNotFoundException {
ByteArrayInputStream bis = new ByteArrayInputStream(bytes);
ObjectInputStream ois = new ObjectInputStream(bis);
HuffmanTree tree = (HuffmanTree) ois.readObject();
ois.close();
bis.close();
return tree;
}
}
public class Main {
public static void main(String[] args) throws IOException, ClassNotFoundException {
// 构建哈夫曼树
HuffmanNode node1 = new HuffmanNode(1);
HuffmanNode node2 = new HuffmanNode(2);
HuffmanNode node3 = new HuffmanNode(3);
HuffmanNode node4 = new HuffmanNode(4);
node1.setLeftChild(node2);
node1.setRightChild(node3);
node3.setRightChild(node4);
HuffmanTree tree = new HuffmanTree();
tree.setRoot(node1);
// 序列化
byte[] bytes = HuffmanSerDes.serialize(tree);
// 反序列化
HuffmanTree tree2 = HuffmanSerDes.deserialize(bytes);
System.out.println(tree2.getRoot().getRightChild().getRightChild().getWeight()); // 输出 4
}
}
基于最新版ChatGPT4的回答,望采纳!!!有其他问题也可以询问我哦、”(最新版更智能,功能更加强大)
在 Java 中实现 SerDes 接口并完成 HuffmanTree 类的序列化与反序列化的示例如下:
首先,创建一个 SerDes 接口,包含两个方法:serialize 和 deserialize。
import java.io.*;
public interface SerDes<T> {
String serialize(T obj) throws IOException;
T deserialize(String data) throws IOException, ClassNotFoundException;
}
然后,实现一个简单的 HuffmanTree 类:
import java.util.HashMap;
import java.util.Map;
import java.util.PriorityQueue;
public class HuffmanTree {
private Node root;
private static class Node implements Comparable<Node> {
int frequency;
char character;
Node left;
Node right;
Node(char character, int frequency) {
this.character = character;
this.frequency = frequency;
}
Node(Node left, Node right) {
this.left = left;
this.right = right;
this.frequency = left.frequency + right.frequency;
}
@Override
public int compareTo(Node other) {
return Integer.compare(this.frequency, other.frequency);
}
boolean isLeaf() {
return left == null && right == null;
}
}
// 构造一个HuffmanTree,传入字符频率映射
public HuffmanTree(Map<Character, Integer> charFrequencies) {
PriorityQueue<Node> priorityQueue = new PriorityQueue<>();
for (Map.Entry<Character, Integer> entry : charFrequencies.entrySet()) {
priorityQueue.offer(new Node(entry.getKey(), entry.getValue()));
}
while (priorityQueue.size() > 1) {
Node left = priorityQueue.poll();
Node right = priorityQueue.poll();
priorityQueue.offer(new Node(left, right));
}
root = priorityQueue.poll();
}
}
接下来,创建一个实现 SerDes 接口的 HuffmanTreeSerDes 类:
import java.io.*;
public class HuffmanTreeSerDes implements SerDes<HuffmanTree> {
@Override
public String serialize(HuffmanTree huffmanTree) throws IOException {
StringBuilder stringBuilder = new StringBuilder();
serialize(huffmanTree.root, stringBuilder);
return stringBuilder.toString();
}
private void serialize(HuffmanTree.Node node, StringBuilder stringBuilder) {
if (node == null) return;
if (node.isLeaf()) {
stringBuilder.append('1');
stringBuilder.append(node.character);
} else {
stringBuilder.append('0');
serialize(node.left, stringBuilder);
serialize(node.right, stringBuilder);
}
}
@Override
public HuffmanTree deserialize(String data) throws IOException {
int[] index = new int[1];
return new HuffmanTree(deserialize(data, index));
}
private HuffmanTree.Node deserialize(String data, int[] index) {
if (index[0] >= data.length()) return null;
boolean isLeaf = data.charAt(index[0]) == '1';
index[0]++;
if (isLeaf) {
char character = data.charAt(index[0]);
index[0]++;
return new HuffmanTree.Node(character, -1);
} else {
HuffmanTree.Node left = deserialize(data, index);
HuffmanTree.Node right = deserialize(data, index);
return new HuffmanTree.Node(left, right);
}
}
}
在此示例中,我们将创建一个 HuffmanTree 并使用 HuffmanTreeSerDes 对其进行序列化和反序列化。
import java.util.HashMap;
import java.util.Map;
public class Main {
public static void main(String[] args) throws IOException, ClassNotFoundException {
// 创建字符频率映射
Map<Character, Integer> charFrequencies = new HashMap<>();
charFrequencies.put('a', 5);
charFrequencies.put('b', 9);
charFrequencies.put('c', 12);
charFrequencies.put('d', 13);
charFrequencies.put('e', 16);
charFrequencies.put('f', 45);
// 根据映射创建 HuffmanTree
HuffmanTree huffmanTree = new HuffmanTree(charFrequencies);
// 创建 HuffmanTreeSerDes 对象并对 HuffmanTree 进行序列化
HuffmanTreeSerDes serDes = new HuffmanTreeSerDes();
String serializedData = serDes.serialize(huffmanTree);
System.out.println("Serialized HuffmanTree: " + serializedData);
// 反序列化 HuffmanTree
HuffmanTree deserializedHuffmanTree = serDes.deserialize(serializedData);
// 序列化反序列化后的 HuffmanTree
String serializedData2 = serDes.serialize(deserializedHuffmanTree);
System.out.println("Serialized deserialized HuffmanTree: " + serializedData2);
// 检查反序列化是否成功
if (serializedData.equals(serializedData2)) {
System.out.println("Deserialization is successful.");
} else {
System.out.println("Deserialization failed.");
}
}
}
以下答案由GPT-3.5大模型与博主波罗歌共同编写:
SerDes接口是一个序列化与反序列化方法的接口,通过序列化方法将对象转换成字节数组或字符串,方便存储和传输,通过反序列化方法将字节数组或字符串还原成对象。具体实现方式因语言而异,可以使用Java、Python等不同的语言来实现。
下面给出Java语言的实现方式,包含了一个HuffmanTree类和一个SerDes接口的定义。
HuffmanTree类实现了根据输入的文本生成Huffman树、获取字符编码、根据编码来对文本进行编码和解码等功能。
```java
import java.io.;
import java.util.;
public class HuffmanTree {
/**
* 哈夫曼编码
*/
private Map<Character, String> code = null;
/**
* 生成的huffman树根结点
*/
private HTNode tree = null;
/**
* 根据初始的
如果我的回答解决了您的问题,请采纳!
提供参考实例:https://blog.csdn.net/tree_ifconfig/article/details/82766587