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1
8
9 package beaver.comp.io;
10
11 import java.io.File  ;
12 import java.io.FileReader ;
13 import java.io.IOException ;
14 import java.io.Reader ;
15
16 import beaver.comp.util.IntArray;
17
18
21 public class SrcReader extends Reader
22 {
23 public final File file;
24
25 protected char[] txt;
26 protected IntArray lines;
27
28 private int ptr;
29
30 public SrcReader(File src_file) throws IOException
31 {
32 super();
33 this.file = src_file;
34
35 Reader txt_reader = new FileReader (src_file);
36 try
37 {
38 txt = new char[(int) src_file.length()];
39 txt_reader.read(txt);
40 }
41 finally
42 {
43 txt_reader.close();
44 }
45 lines = new IntArray(txt.length / 20 + 20);
46
47 boolean eol = true, cr = false;
48 for (int i = 0; i < txt.length; i++)
49 {
50 if (eol)
51 {
52 lines.add(i);
53 eol = false;
54 }
55 switch (txt[i])
56 {
57 case '\u000B':
58 case '\u000C':
59 case '\u0085':
60 case '\u2028':
61 case '\u2029':
62 {
63 eol = true;
64 cr = false;
65 break;
66 }
67 case '\r':
68 {
69 if (cr)
70 eol = true;
71 cr = true;
72 break;
73 }
74 case '\n':
75 {
76 if (cr)
77 cr = false;
78 eol = true;
79 break;
80 }
81 default:
82 {
83 if (cr)
84 eol = true;
85 cr = false;
86 }
87 }
88 }
89 }
90
91 public int read(char[] buf, int off, int len)
92 {
93 int copy_max = txt.length - ptr;
94 if (copy_max <= 0)
95 return -1;
96 int copy_len = Math.min(copy_max, len);
97 if (copy_len > 0)
98 {
99 System.arraycopy(txt, ptr, buf, off, copy_len);
100 ptr += copy_len;
101 }
102 return copy_len;
103 }
104
105 public void reset()
106 {
107 ptr = 0;
108 }
109
110 public void close()
111 {
112 }
113
114 public String getLine(int n)
115 {
116 int line_start = lines.get(n - 1);
117 int line_len = (n == lines.size() ? txt.length : lines.get(n)) - line_start;
118 return new String (txt, line_start, line_len);
119 }
120 } |
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