我有使用霍夫曼压缩的压缩字符串数据的编码，即“需要更多的钱”
编码
\n 0110
1011
d 100
e 11
m 001
n 000
o 010
r 0111
y 1010
**
001010011111101100101000011101010110001111100111000110
我想在java中重建霍夫曼树来解码编码。这种解码的任何实现或示例。
我尝试并编写了完美的解决方案。
public class HuffmanTree {
public Node root;
public HuffmanTree(){
this.root = new Node();
}
public void add(char data, String sequence){
Node temp = this.root;
int i = 0;
for(i=0;i<sequence.length()-1;i++){
if(sequence.charAt(i)=='0'){
if(temp.left == null){
temp.left = new Node();
temp = temp.left;
}
else{
temp = (Node) temp.left;
}
}
else
if(sequence.charAt(i)=='1'){
if(temp.right == null){
temp.right = new Node();
temp = temp.right;
}
else{
temp = (Node) temp.right;
}
}}
if(sequence.charAt(i)=='0'){
temp.left = new Node(data);
}
else{
temp.right = new Node(data);
}
}
public String getDecodedMessage(String encoding){
String output = "";
Node temp = this.root;
for(int i = 0;i<encoding.length();i++){
if(encoding.charAt(i) == '0'){
temp = temp.left;
if(temp.left == null && temp.right == null){
output+= temp.getData();
temp = this.root;
}
}
else
{
temp = temp.right;
if(temp.left == null && temp.right == null){
output+= temp.getData();
temp = this.root;
}
}
}
return output;
}
// Traversal of reconstructed huffman tree for debugging.
public void traversal(Node node){
if(node == null)
return;
System.out.println(node);
traversal(node.left);
traversal(node.right);
}
}
class Node{
Node left;
Node right;
char data;
public Node(){
}
public Node(char data){
this.data = data;
}
public void setData(char data){
this.data = data;
}
public char getData(){
return this.data;
}
@Override
public String toString(){
if(this.data == Character.UNASSIGNED){
return "No Value";
}
else
return ""+this.data;
}
}
如果您在文本文件中有编码消息，则空格字符可能会导致任何问题，因此我也为此编写了代码。
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Scanner;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Test {
public static void main(String[] bscs){
HuffmanTree tree = new HuffmanTree();
String inputFile;
String outputFile;
Scanner kb = new Scanner(System.in);
System.out.println("Please enter the name of the Input File");
inputFile = kb.nextLine();
File f = new File(inputFile);
Scanner fr = null;
try {
fr = new Scanner(new File(inputFile));
fr.nextLine();
tree.add('\n', fr.nextLine().trim());
String temp = fr.nextLine();
if(temp.charAt(0)==' ' && temp.charAt(1)==' ')
{
tree.add(' ', temp.trim());
}
else
tree.add(temp.charAt(0), temp.substring(1));
while(fr.hasNext()){
temp = fr.nextLine();
if(temp.equals("**")){
break;
}
else
tree.add(temp.charAt(0), temp.substring(1));
}
FileWriter f0 = new FileWriter(new File("decoded.ou"));
f0.write(tree.getDecodedMessage(fr.nextLine()));
f0.close();
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
}
}