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21
22 package org.armedbear.j;
23
24 import java.io.BufferedReader  ;
25 import java.io.BufferedWriter ;
26 import java.io.IOException ;
27 import java.io.InputStream ;
28 import java.io.InputStreamReader ;
29 import java.io.OutputStream ;
30 import java.io.OutputStreamWriter ;
31 import java.net.HttpURLConnection ;
32 import java.net.URL ;
33 import java.util.Vector ;
34
35 public final class Cache
36 {
37 private static final File cacheDir =
38 File.getInstance(Directories.getEditorDirectory(), "cache");
39
40 private static Cache cache;
41
42 private File catalogFile;
43 private Vector catalog;
44
45 private Cache()
46 {
47 }
48
49 public static Cache getCache()
50 {
51 if (cache == null) {
52 cache = new Cache();
53 if (!cache.initialize())
54 cache = null;
55 }
56 return cache;
57 }
58
59 public static void cleanup()
62 {
63 if (cacheDir.isDirectory()) {
64 String [] files = cacheDir.list();
65 for (int i = files.length-1; i >= 0; i--) {
66 File file = File.getInstance(cacheDir, files[i]);
67 file.delete();
68 }
69 }
70 }
71
72 private boolean initialize()
73 {
74 if (!cacheDir.isDirectory())
75 cacheDir.mkdirs();
76 if (!cacheDir.isDirectory())
77 return false;
78 catalogFile = File.getInstance(cacheDir, "catalog");
79 catalog = loadCatalog();
80 return true;
81 }
82
83 public File get(String netPath)
84 {
85 for (int i = catalog.size()-1; i >= 0; i--) {
86 StringPair pair = (StringPair) catalog.get(i);
87 if (pair.second.equals(netPath))
88 return File.getInstance(cacheDir, pair.first);
89 }
90 return null;
91 }
92
93 public File put(String netPath)
94 {
95 File file = null;
96 try {
97 URL url = new URL (netPath);
98 HttpURLConnection connection =
99 (HttpURLConnection ) url.openConnection();
100 InputStream in = connection.getInputStream();
101 if (in != null) {
102 file = Utilities.getTempFile(cacheDir);
103 OutputStream out = file.getOutputStream();
104 byte[] buf = new byte[4096];
105 int bytesRead;
106 while ((bytesRead = in.read(buf)) > 0)
107 out.write(buf, 0, bytesRead);
108 out.close();
109 in.close();
110 }
111 }
112 catch (IOException e) {
113 Log.error(e);
114 if (file.exists())
115 file.delete();
116 file = null;
117 }
118 if (file != null) {
119 catalog.add(new StringPair(file.getName(), netPath));
120 saveCatalog();
121 }
122 return file;
123 }
124
125 private Vector loadCatalog()
126 {
127 Vector v = new Vector ();
128 if (catalogFile.exists()) {
129 try {
130 BufferedReader reader = new BufferedReader (
131 new InputStreamReader (catalogFile.getInputStream()));
132 String s;
133 while ((s = reader.readLine()) != null) {
134 int index = s.indexOf(' ');
135 if (index >= 0)
136 v.add(new StringPair(s.substring(0, index), s.substring(index+1)));
137 }
138 }
139 catch (IOException e) {
140 Log.error(e);
141 }
142 }
143 return v;
144 }
145
146 private void saveCatalog()
147 {
148 try {
149 BufferedWriter writer = new BufferedWriter (
150 new OutputStreamWriter (catalogFile.getOutputStream()));
151 for (int i = 0; i < catalog.size(); i++) {
152 StringPair pair = (StringPair) catalog.get(i);
153 writer.write(pair.first);
154 writer.write(' ');
155 writer.write(pair.second);
156 writer.newLine();
157 }
158 writer.flush();
159 writer.close();
160 }
161 catch (IOException e) {
162 Log.error(e);
163 }
164 }
165 }
166 |
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