一些ActionScript LZW壓縮解壓縮的資源：
LZW Algorithms：
其實Flash 8 ActionScript LZW幾百kb的資料，速度還算OK
不過千萬不要貿貿然地，就把程式copy去用
建議多K一下HTTP規格以及Flash Doc再來用
免得資料傳輸量沒減少，反而暴增~~
以下是直接從AS版的LZW改成Java版的LZW：
| Java LZW |
1 package idv.ticore.compress;
2 import java.util.*;
3
4 public class LZW {
5 private static boolean xmlsafe = false;
6 private LZW() {
7 }
8 public static String compress(String str) {
9
10 Map dico = new HashMap();
11 int skipnum = xmlsafe ? 5 : 0;
12 for (char i = 0 ; i < 256 ; ++i) {
13 dico.put(Character.toString(i), new Character(i));
14 }
15 if (xmlsafe) {
16 dico.put("<", new Character((char)256));
17 dico.put(">", new Character((char)257));
18 dico.put("&", new Character((char)258));
19 dico.put(""", new Character((char)259));
20 dico.put(""", new Character((char)260));
21 }
22 String res = "";
23 String txt2encode = str;
24 String[] splitStr = txt2encode.split("");
25 int len = splitStr.length;
26 int nbChar = 256 + skipnum;
27 String buffer = "";
28
29 for (int i = 1; i <= len; i++) {
30 String current;
31 if(i <= len - 1) {
32 current = splitStr[i];
33 } else {
34 current = null;
35 }
36 if(dico.get(buffer + current) != null) {
37 buffer += current;
38 } else {
39 res += ((Character)dico.get(buffer)).toString();
40
41 dico.put(buffer + current, new Character((char)nbChar));
42 nbChar++;
43 buffer = current;
44 }
45 }
46 return res;
47 }
48
49 public static String decompress(String str) {
50 Map dico = new HashMap();
51 int skipnum = xmlsafe ? 5 : 0;
52 for (int i = 0 ; i < 256 ; ++i) {
53 dico.put(Integer.toString(i), Character.toString((char)i));
54 }
55 if (xmlsafe) {
56 dico.put("256", "<");
57 dico.put("257", ">");
58 dico.put("258", "&");
59 dico.put("259", """);
60 dico.put("260", """);
61 }
62 String txt2encode = str;
63 String[] splitStr = txt2encode.split("");
64 int len = splitStr.length;
65 int nbChar = 256 + skipnum;
66 String buffer = "";
67 String chaine = "";
68 String res = "";
69
70 for (int i = 1; i < len; i++) {
71 int code = txt2encode.charAt(i - 1);
72 String current = (String)dico.get(Integer.toString(code));
73 if (buffer == "") {
74 buffer = current;
75 res += current;
76 } else {
77 if (code <= 255 + skipnum) {
78 res += current;
79 chaine = buffer + current;
80 dico.put("" + nbChar, chaine);
81 nbChar++;
82 buffer = current;
83 } else {
84 chaine = (String)dico.get("" + code);
85 if (chaine == null) {
86 chaine = buffer + buffer.substring(0, 1);
87 }
88 res += chaine;
89 dico.put("" + nbChar, buffer + chaine.substring(0, 1));
90 nbChar++;
91 buffer = chaine;
92 }
93 }
94 }
95 return res;
96 }
97 }
98 |
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