1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
import java.io.*;
%%
%public
%class ZeroLexer
%int
%{
public static void main(String argv[]) {
if (argv.length == 0) {
System.out.println("Usage : java ZeroLexer [ --encoding <name> ] <inputfile(s)>");
}
else {
int firstFilePos = 0;
String encodingName = "UTF-8";
if (argv[0].equals("--encoding")) {
firstFilePos = 2;
encodingName = argv[1];
try {
java.nio.charset.Charset.forName(encodingName); // Side-effect: is encodingName valid?
} catch (Exception e) {
System.out.println("Invalid encoding '" + encodingName + "'");
return;
}
}
for (int i = firstFilePos; i < argv.length; i++) {
ZeroLexer scanner = null;
try {
FileInputStream stream = new FileInputStream(argv[i]);
// the usual Reader:
Reader reader = new InputStreamReader(stream, encodingName);
// the broken 0-returning Reader:
reader = new FunkyReader(reader);
try {
scanner = new ZeroLexer(reader);
do {
System.out.println(scanner.yylex());
System.out.println("--"+scanner.yytext()+"--");
} while (!scanner.zzAtEOF);
}
catch (IOException e) {
System.out.println("Expected IO exception");
}
reader.close();
stream = new FileInputStream(argv[i]);
reader = new InputStreamReader(stream, encodingName);
reader = new FunkyReader(reader);
// now the wrapper for broken Readers:
reader = new ZeroReader(reader);
scanner = new ZeroLexer(reader);
do {
System.out.println(scanner.yylex());
System.out.println("--"+scanner.yytext()+"--");
} while (!scanner.zzAtEOF);
}
catch (java.io.FileNotFoundException e) {
System.out.println("File not found : \""+argv[i]+"\"");
}
catch (java.io.IOException e) {
System.out.println("IO error scanning file \""+argv[i]+"\"");
System.out.println(e);
}
catch (Exception e) {
System.out.println("Unexpected exception:");
e.printStackTrace();
}
}
}
}
%}
%%
"some longer fixed-length match" { return 1; }
"a"+ { return 2; }
[^] { return 3; }
<<EOF>> { return YYEOF; }
|
