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1 package gnu.jemacs.buffer;
2 import gnu.mapping.*;
3
4
7
8 public class BufferLocal extends IndirectableLocation
9 {
10 boolean all;
11
12 final Symbol name;
13
14 Buffer cachedBuffer;
15
16
17 int cachedIndex;
18
19 BufferLocal (Symbol name, boolean all)
20 {
21 this.name = name;
22 this.all = all;
23 }
24
25 public final Symbol getKeySymbol ()
26 {
27 return name;
28 }
29
30 public static void make(Symbol symbol, boolean all)
31 {
32 Environment env = Environment.getCurrent();
33 NamedLocation loc = env.getLocation(symbol, null, true);
34 Location base = loc.getBase();
35 if (base instanceof BufferLocal)
36 {
37 if (all)
38 ((BufferLocal) base).all = true;
39 return;
40 }
41 BufferLocal bloc = new BufferLocal(symbol, all);
42 bloc.base = loc.getBaseForce();
45 bloc.setAlias(loc);
46 }
47
48 public Object  get (Object defaultValue)
49 {
50 Buffer buffer = Buffer.getCurrent();
51 return buffer == null ? base.get(defaultValue) : get(buffer, defaultValue);
52 }
53
54 public Object get (Buffer buffer, Object defaultValue)
55 {
56 Object [] localBindings = buffer.localBindings;
57 if (buffer == cachedBuffer)
58 {
59 int i = cachedIndex;
60 if (i > 0)
61 return localBindings[i];
62 }
63 else if (localBindings != null)
64 {
65 Symbol n = this.getKeySymbol();
66 int len = localBindings.length;
67 cachedBuffer = buffer;
68 for (int i = 0; i < len; i += 2)
69 {
70 if (localBindings[i] == n)
71 {
72 cachedIndex = ++i;
73 return localBindings[i];
74 }
75 }
76 cachedIndex = 0;
77 }
78 return base != null ? base.get(defaultValue)
79 : value == Location.UNBOUND ? defaultValue : value;
80 }
81
82 public boolean isBound ()
83 {
84 Buffer buffer = Buffer.getCurrent();
85 return buffer == null ? base.isBound() : isBound(buffer);
86 }
87
88 public boolean isBound (Buffer buffer)
89 {
90 Object [] localBindings = buffer.localBindings;
91 Object unb = Location.UNBOUND;
92 if (buffer == cachedBuffer)
93 {
94 int i = cachedIndex;
95 if (i >= 0)
96 return localBindings[i] != unb;
97 }
98 else if (localBindings != null)
99 {
100 Symbol n = this.getKeySymbol();
101 int len = localBindings.length;
102 cachedBuffer = buffer;
103 for (int i = 0; i < len; i += 2)
104 {
105 if (localBindings[i] == n)
106 {
107 cachedIndex = ++i;
108 return localBindings[i] != unb;
109 }
110 }
111 cachedIndex = 0;
112 }
113 return super.isBound();
114 }
115
116 public synchronized final void set (Object newValue)
117 {
118 Buffer buffer = Buffer.getCurrent();
119 if (buffer == null)
120 base.set(newValue);
121 else
122 set(buffer, newValue);
123 }
124
125 public synchronized final void set (Buffer buffer, Object newValue)
126 {
127 Object [] localBindings = buffer.localBindings;
128 int avail = -1;
129 Symbol n = this.getKeySymbol();
130 if (buffer == cachedBuffer)
131 {
132 int i = cachedIndex;
133 if (i >= 0)
134 {
135 localBindings[i] = newValue;
136 return;
137 }
138 }
139 else if (localBindings != null)
140 {
141 int len = localBindings.length;
142 for (int i = 0; i < len; i += 2)
143 {
144 Object key = localBindings[i];
145 if (key == n)
146 {
147 cachedBuffer = buffer;
148 cachedIndex = ++i;
149 localBindings[i] = newValue;
150 return;
151 }
152 if (key == null)
153 avail = i;
154 }
155 cachedIndex = 0;
156 }
157 if (all)
158 {
159 if (avail < 0)
160 {
161 if (localBindings == null)
162 {
163 localBindings = new Object [20];
164 buffer.localBindings = localBindings;
165 avail = 0;
166 }
167 else
168 {
169 avail = localBindings.length;
170 Object [] newBindings = new Object [2 * avail];
171 System.arraycopy(localBindings, 0, newBindings, 0, avail);
172 buffer.localBindings = localBindings = newBindings;
173 }
174 }
175 localBindings[avail] = n;
176 cachedBuffer = buffer;
177 cachedIndex = ++avail;
178 localBindings[avail] = newValue;
179 }
180 else if (base == null)
181 value = newValue;
182 else
183 base.set(newValue);
184 }
185 }
186 |
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