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1
4 package gnu.text;
5 import java.util.Hashtable  ;
6 import java.util.Vector ;
7 import java.util.Enumeration ;
8
9
11
12 public class Options
13 {
14
15 public static final int BOOLEAN_OPTION = 1;
16
17 public static final int STRING_OPTION = 2;
18
19
20 Options previous;
21
22 OptionInfo first;
23 OptionInfo last;
24
25 public Options ()
26 {
27 }
28
29 public Options (Options previous)
30 {
31 this.previous = previous;
32 }
33
34
35 Hashtable valueTable;
36
37
38 Hashtable infoTable;
39
40
45 public void add(String key, int kind, String documentation)
46 {
47 if (infoTable == null)
48 infoTable = new Hashtable ();
49 else if (infoTable.get(key) != null)
50 throw new RuntimeException ("duplicate option key: "+key);
51 OptionInfo info = new OptionInfo();
52 info.key = key;
53 info.kind = kind;
54 info.documentation = documentation;
55 if (first == null)
56 first = info;
57 else
58 last.next = info;
59 last = info;
60 infoTable.put(key, info);
61 }
62
63 static Object valueOf (OptionInfo info, String argument)
64 {
65 if ((info.kind & BOOLEAN_OPTION) != 0)
66 {
67 if (argument == null
68 || argument.equals("1")
69 || argument.equals("on")
70 || argument.equals("yes")
71 || argument.equals("true"))
72 return Boolean.TRUE;
73 if (argument.equals("0")
74 || argument.equals("off")
75 || argument.equals("no")
76 || argument.equals("false"))
77 return Boolean.FALSE;
78 return null;
79 }
80 return argument;
81 }
82
83 private void error(String message, SourceMessages messages)
84 {
85 if (messages == null)
86 throw new RuntimeException (message);
87 else
88 messages.error('e', message);
89 }
90
91
92 public void set (String key, Object value)
93 {
94 set(key, value, null);
95 }
96
97
98 public void set (String key, Object value, SourceMessages messages)
99 {
100 OptionInfo info = getInfo(key);
101 if (info == null)
102 {
103 error("invalid option key: "+key, messages);
104 return;
105 }
106 if ((info.kind & BOOLEAN_OPTION) != 0)
107 {
108 if (value instanceof String )
109 value = valueOf(info, (String ) value);
110 if (! (value instanceof Boolean ))
111 {
112 error("value for option "+key
113 +" must be boolean or yes/no/true/false/on/off/1/0",
114 messages);
115 return;
116 }
117 }
118 else if (value == null)
119 value = "";
120 if (valueTable == null)
121 valueTable = new Hashtable ();
122 valueTable.put(key, value);
123 }
124
125
126 public void reset (String key, Object oldValue)
127 {
128 if (valueTable == null)
129 valueTable = new Hashtable ();
130 if (oldValue == null)
131 valueTable.remove(key);
132 else
133 valueTable.put(key, oldValue);
134 }
135
136 public static final String UNKNOWN = "unknown option name";
137
138
141 public String set (String key, String argument)
142 {
143 OptionInfo info = getInfo(key);
144 if (info == null)
145 return UNKNOWN;
146 Object value = valueOf(info, argument);
147 if (value == null)
148 {
149 if ((info.kind & BOOLEAN_OPTION) != 0)
150 return "value of option "+key+" must be yes/no/true/false/on/off/1/0";
151 }
152 if (valueTable == null)
153 valueTable = new Hashtable ();
154 valueTable.put(key, value);
155 return null;
156 }
157
158 public OptionInfo getInfo (String key)
159 {
160 Object info = infoTable == null ? null : infoTable.get(key);
161 if (info == null && previous != null)
162 info = previous.getInfo(key);
163 return (OptionInfo) info;
164 }
165
166
170 public Object get (String key, Object defaultValue)
171 {
172 Object val = valueTable == null ? null : valueTable.get(key);
173 if (val != null)
174 return val;
175 if (previous != null)
176 return previous.get(key, defaultValue);
177 OptionInfo info = getInfo(key);
178 if (info == null)
179 throw new RuntimeException ("invalid option key: "+key);
180 return defaultValue;
181 }
182
183
188 public Object getLocal (String key)
189 {
190 return valueTable == null ? null : valueTable.get(key);
191 }
192
193 public boolean getBoolean (String key)
194 {
195 return ((Boolean ) get (key, Boolean.FALSE)).booleanValue();
196 }
197
198 public boolean getBoolean (String key, boolean defaultValue)
199 {
200 Boolean defaultObject = defaultValue ? Boolean.TRUE : Boolean.FALSE;
201 return ((Boolean ) get (key, defaultObject)).booleanValue();
202 }
203
204
210 public void pushOptionValues (Vector options)
211 {
212 int len = options.size();
213 for (int i = 0; i < len; )
214 {
215 String key = (String ) options.elementAt(i++);
216 Object newValue = options.elementAt(i);
217 options.setElementAt(newValue, i++);
218 set(key, options.elementAt(i++));
219 }
220 }
221
222
224 public void popOptionValues (Vector options)
225 {
226 for (int i = options.size(); (i -= 3) >= 0; )
227 {
228 String key = (String ) options.elementAt(i);
229 Object oldValue = options.elementAt(i+1);
230 options.setElementAt(null, i+1);
231 reset(key, oldValue);
232 }
233 }
234
235
237 public Vector keys ()
238 {
239 Vector allKeys = new Vector ();
240 for (Options options = this; options != null; options = options.previous)
241 {
242 if (options.infoTable != null)
243 {
244 Enumeration e = options.infoTable.keys();
245 while (e.hasMoreElements())
246 {
247 Object k = e.nextElement();
248 if (! allKeys.contains(k))
249 allKeys.add(k);
250 }
251 }
252 }
253 return allKeys;
254 }
255
256 public String getDoc(String key)
257 {
258 OptionInfo info = getInfo(key);
259 if (key == null)
260 return null;
261 return info.documentation;
262 }
263
264 }
265
266 final class OptionInfo
267 {
268 OptionInfo next;
269 String key;
270 int kind;
271 String documentation;
272 }
273 |
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