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1
30
31 package rcm.util;
32
33 import java.util.*;
34 import java.io.*;
35
36 public class Config extends Properties {
37 File file;
38 IOException lastException;
39
40 public Config (String  fileBaseName) {
41 this (fileBaseName, null);
42 }
43
44 public Config (File file) {
45 this (file, null);
46 }
47
48 public Config (String fileBaseName, Config defaults) {
49 this (new File (getHomeDirectory (), fileBaseName),
50 defaults);
51 }
52
53 public Config (File file, Config defaults) {
54 super (defaults);
55
56 this.file = file;
57 try {
58 FileInputStream in =
59 new FileInputStream (file);
60 load (in);
61 in.close ();
62 } catch (IOException e) {
63 lastException = e;
64 }
65 }
66
67 public IOException getLastException () {
68 return lastException;
69 }
70
71
78 public void save () {
79 try {
80 FileOutputStream out = new FileOutputStream (file);
81 save (out, "");
82 out.close ();
83 lastException = null;
84 } catch (IOException e) {
85 lastException = e;
86 }
87 }
88
89 public int countKeysStartingWith (String prefix) {
90 int n = 0;
91 for (Enumeration e = propertyNames (); e.hasMoreElements (); ) {
92 String name = (String )e.nextElement ();
93 if (name.startsWith (prefix))
94 ++n;
95 }
96 return n;
97 }
98
99 public void removeAllKeysStartingWith (String prefix) {
100 Vector keysToDelete = new Vector ();
101 for (Enumeration e = propertyNames (); e.hasMoreElements (); ) {
102 String name = (String )e.nextElement ();
103 if (name.startsWith (prefix))
104 keysToDelete.addElement (name);
105 }
106
107 for (Enumeration e = keysToDelete.elements ();
108 e.hasMoreElements (); )
109 remove (e.nextElement ());
110 }
111
112 public static File getHomeDirectory () {
113 String homedir;
114 if ((homedir = System.getProperty ("user.home")) == null
115 && (homedir = System.getProperty ("user.dir")) == null)
116 homedir = ".";
117
118 return new File (homedir);
119 }
120 }
121 |
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