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1
3 package gnu.jemacs.swt;
4
5 import gnu.lists.FString;
6 import gnu.lists.GapVector;
7
8
13 public class SwtCharBuffer extends GapVector implements CharSequence 
14 {
15 protected FString chars;
16 protected LineOffsets lineOffsets;
17
18 public SwtCharBuffer(int initialSize)
19 {
20 super(new FString(new char[initialSize]));
21 chars = (FString) base;
22 this.lineOffsets = new LineOffsets(initialSize/50);
23 }
24
25
26 public CharSequence subSequence(int start, int end)
27 {
28 return new SubSequence(start, end);
29 }
30
31 class SubSequence implements CharSequence
32 {
33 private int start;
34 private int end;
35
36 public SubSequence(int start, int end)
37 {
38 this.start = start;
39 this.end = end;
40 }
41
42
45 public int length()
46 {
47 return end - start;
48 }
49
50
53 public char charAt(int index)
54 {
55 return SwtCharBuffer.this.charAt(index + start);
56 }
57
58
61 public CharSequence subSequence(int start, int end)
62 {
63 return SwtCharBuffer.this.subSequence(this.start + start, this.start + end);
64 }
65 }
66
67
68 public int pos2offset(int pos)
69 {
70 return pos < gapStart ? pos : pos + gapEnd - gapStart;
71 }
72
73 public int offset2pos(int offset)
74 {
75 return offset <= gapStart ? offset : offset - gapEnd + gapStart;
76 }
77
78
81 protected void gapReserve(int size)
82 {
83 int oldGapSize = gapEnd - gapStart;
84 super.gapReserve(size);
85 int newGapSize = gapEnd - gapStart;
86 if (newGapSize > oldGapSize) {
88 lineOffsets.textRegionMoved(gapStart + oldGapSize, size(), newGapSize - oldGapSize);
89 }
90 }
91
94 protected void shiftGap(int newGapStart)
95 {
96 int oldGapStart = gapStart;
97 super.shiftGap(newGapStart);
98 if (oldGapStart != gapStart)
99 {
100 int regionStart = oldGapStart < newGapStart ? oldGapStart + gapEnd - gapStart : gapStart;
101 int regionEnd = oldGapStart < newGapStart ? gapEnd : oldGapStart;
102 int displacement = oldGapStart < newGapStart ? gapStart - gapEnd : gapEnd - gapStart;
103 lineOffsets.textRegionMoved(regionStart, regionEnd, displacement);
104
105 }
106 }
107
110 public int length()
111 {
112 return size();
113 }
114
115
118 public char charAt(int index)
119 {
120 char c = chars.charAt(index < gapStart ? index : index + gapEnd - gapStart);
121 return c;
122 }
123
127 public void insert(int where, String str)
128 {
129 gapReserve(where, str.length());
130 str.getChars(0, str.length(), chars.data, where);
131 gapStart += str.length();
132 lineOffsets.textInserted(where, str);
133 }
134
135
139 public void delete(int where, int count)
140 {
141 shiftGap(where + count);
142 gapStart -= count;
143 lineOffsets.textDeleted(where, where + count);
144 }
145
146 public void getChars(int start, int end, char[] dest, int destStart)
147 {
148 int startOffset = pos2offset(start);
149 int endOffset = pos2offset(end);
150 int startOffset1 = Math.min(startOffset, gapStart);
152 int len1 = Math.min(endOffset, gapStart) - startOffset1;
153 System.arraycopy(chars.data, startOffset1, dest, destStart, len1);
154
155 int startOffset2 = Math.max(startOffset, gapEnd);
157 int len2 = Math.max(endOffset, gapEnd) - startOffset2;
158 System.arraycopy(chars.data, startOffset2, dest, destStart + len1, len2);
159 }
160
161 public String toString()
162 {
163 StringBuffer sbuf = new StringBuffer ();
164 sbuf.append("Text: {" + size() + ", " + gapStart + ", " + gapEnd);
165 sbuf.append(" [");
166 for (int i = 0; i < size(); i++)
167 {
168 if (i == gapStart)
169 {
170 sbuf.append("|");
171 }
172 char c = chars.charAt(i < gapStart ? i : i + gapEnd - gapStart);
173 if (c == '\r') c = 'R';
174 if (c == '\n') c = 'N';
175 sbuf.append(c);
176 }
177 sbuf.append("]}\n");
178 sbuf.append(lineOffsets.toString());
179
180 return sbuf.toString();
181
182
183 }
184
185
186
189 protected void show()
190 {
191 System.out.println(this);
192 }
193
194 protected static String printable(String s)
195 {
196 return ">>" + s.replaceAll("\r", "R").replaceAll("\n", "N") + "<<";
197 }
198
199
200 }
201 |
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