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Java > Open Source Codes > JSci > maths > symbolic > TokenMgrError


1 /* Generated By:JavaCC: Do not edit this line. TokenMgrError.java Version 3.0 */
2 package JSci.maths.symbolic;
3
4 class TokenMgrError extends Error JavaDoc
5 {
6    /*
7     * Ordinals for various reasons why an Error of this type can be thrown.
8     */
9
10    /**
11     * Lexical error occured.
12     */
13    static final int LEXICAL_ERROR = 0;
14
15    /**
16     * An attempt wass made to create a second instance of a static token manager.
17     */
18    static final int STATIC_LEXER_ERROR = 1;
19
20    /**
21     * Tried to change to an invalid lexical state.
22     */
23    static final int INVALID_LEXICAL_STATE = 2;
24
25    /**
26     * Detected (and bailed out of) an infinite loop in the token manager.
27     */
28    static final int LOOP_DETECTED = 3;
29
30    /**
31     * Indicates the reason why the exception is thrown. It will have
32     * one of the above 4 values.
33     */
34    int errorCode;
35
36    /**
37     * Replaces unprintable characters by their espaced (or unicode escaped)
38     * equivalents in the given string
39     */
40    protected static final String JavaDoc addEscapes(String JavaDoc str) {
41       StringBuffer JavaDoc retval = new StringBuffer JavaDoc();
42       char ch;
43       for (int i = 0; i < str.length(); i++) {
44         switch (str.charAt(i))
45         {
46            case 0 :
47               continue;
48            case '\b':
49               retval.append("\\b");
50               continue;
51            case '\t':
52               retval.append("\\t");
53               continue;
54            case '\n':
55               retval.append("\\n");
56               continue;
57            case '\f':
58               retval.append("\\f");
59               continue;
60            case '\r':
61               retval.append("\\r");
62               continue;
63            case '\"':
64               retval.append("\\\"");
65               continue;
66            case '\'':
67               retval.append("\\\'");
68               continue;
69            case '\\':
70               retval.append("\\\\");
71               continue;
72            default:
73               if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
74                  String JavaDoc s = "0000" + Integer.toString(ch, 16);
75                  retval.append("\\u" + s.substring(s.length() - 4, s.length()));
76               } else {
77                  retval.append(ch);
78               }
79               continue;
80         }
81       }
82       return retval.toString();
83    }
84
85    /**
86     * Returns a detailed message for the Error when it is thrown by the
87     * token manager to indicate a lexical error.
88     * Parameters :
89     * EOFSeen : indicates if EOF caused the lexicl error
90     * curLexState : lexical state in which this error occured
91     * errorLine : line number when the error occured
92     * errorColumn : column number when the error occured
93     * errorAfter : prefix that was seen before this error occured
94     * curchar : the offending character
95     * Note: You can customize the lexical error message by modifying this method.
96     */
97    protected static String JavaDoc LexicalError(boolean EOFSeen, int lexState, int errorLine, int errorColumn, String JavaDoc errorAfter, char curChar) {
98       return("Lexical error at line " +
99            errorLine + ", column " +
100            errorColumn + ". Encountered: " +
101            (EOFSeen ? "<EOF> " : ("\"" + addEscapes(String.valueOf(curChar)) + "\"") + " (" + (int)curChar + "), ") +
102            "after : \"" + addEscapes(errorAfter) + "\"");
103    }
104
105    /**
106     * You can also modify the body of this method to customize your error messages.
107     * For example, cases like LOOP_DETECTED and INVALID_LEXICAL_STATE are not
108     * of end-users concern, so you can return something like :
109     *
110     * "Internal Error : Please file a bug report .... "
111     *
112     * from this method for such cases in the release version of your parser.
113     */
114    public String JavaDoc getMessage() {
115       return super.getMessage();
116    }
117
118    /*
119     * Constructors of various flavors follow.
120     */
121
122    public TokenMgrError() {
123    }
124
125    public TokenMgrError(String JavaDoc message, int reason) {
126       super(message);
127       errorCode = reason;
128    }
129
130    public TokenMgrError(boolean EOFSeen, int lexState, int errorLine, int errorColumn, String JavaDoc errorAfter, char curChar, int reason) {
131       this(LexicalError(EOFSeen, lexState, errorLine, errorColumn, errorAfter, curChar), reason);
132    }
133 }
134
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