org.graphstream.util.parser.ParseException Maven / Gradle / Ivy
/*
* This file is part of GraphStream .
*
* GraphStream is a library whose purpose is to handle static or dynamic
* graph, create them from scratch, file or any source and display them.
*
* This program is free software distributed under the terms of two licenses, the
* CeCILL-C license that fits European law, and the GNU Lesser General Public
* License. You can use, modify and/ or redistribute the software under the terms
* of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
* URL or under the terms of the GNU LGPL as published by
* the Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* This program is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see
* @author Hicham Brahimi
*/
package org.graphstream.util.parser;
/**
* This exception is thrown when parse errors are encountered. You can
* explicitly create objects of this exception type by calling the method
* generateParseException in the generated parser.
*
* You can modify this class to customize your error reporting mechanisms so
* long as you retain the public fields.
*/
public class ParseException extends Exception {
/**
* The version identifier for this Serializable class. Increment only if the
* serialized form of the class changes.
*/
private static final long serialVersionUID = 1L;
/**
* This constructor is used by the method "generateParseException" in the
* generated parser. Calling this constructor generates a new object of this
* type with the fields "currentToken", "expectedTokenSequences", and
* "tokenImage" set.
*/
public ParseException(Token currentTokenVal, int[][] expectedTokenSequencesVal, String[] tokenImageVal) {
super(initialise(currentTokenVal, expectedTokenSequencesVal, tokenImageVal));
currentToken = currentTokenVal;
expectedTokenSequences = expectedTokenSequencesVal;
tokenImage = tokenImageVal;
}
/**
* The following constructors are for use by you for whatever purpose you can
* think of. Constructing the exception in this manner makes the exception
* behave in the normal way - i.e., as documented in the class "Throwable". The
* fields "errorToken", "expectedTokenSequences", and "tokenImage" do not
* contain relevant information. The JavaCC generated code does not use these
* constructors.
*/
public ParseException() {
super();
}
/** Constructor with message. */
public ParseException(String message) {
super(message);
}
/**
* This is the last token that has been consumed successfully. If this object
* has been created due to a parse error, the token followng this token will
* (therefore) be the first error token.
*/
public Token currentToken;
/**
* Each entry in this array is an array of integers. Each array of integers
* represents a sequence of tokens (by their ordinal values) that is expected at
* this point of the parse.
*/
public int[][] expectedTokenSequences;
/**
* This is a reference to the "tokenImage" array of the generated parser within
* which the parse error occurred. This array is defined in the generated
* ...Constants interface.
*/
public String[] tokenImage;
/**
* It uses "currentToken" and "expectedTokenSequences" to generate a parse error
* message and returns it. If this object has been created due to a parse error,
* and you do not catch it (it gets thrown from the parser) the correct error
* message gets displayed.
*/
private static String initialise(Token currentToken, int[][] expectedTokenSequences, String[] tokenImage) {
String eol = System.getProperty("line.separator", "\n");
StringBuffer expected = new StringBuffer();
int maxSize = 0;
for (int i = 0; i < expectedTokenSequences.length; i++) {
if (maxSize < expectedTokenSequences[i].length) {
maxSize = expectedTokenSequences[i].length;
}
for (int j = 0; j < expectedTokenSequences[i].length; j++) {
expected.append(tokenImage[expectedTokenSequences[i][j]]).append(' ');
}
if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
expected.append("...");
}
expected.append(eol).append(" ");
}
String retval = "Encountered \"";
Token tok = currentToken.next;
for (int i = 0; i < maxSize; i++) {
if (i != 0)
retval += " ";
if (tok.kind == 0) {
retval += tokenImage[0];
break;
}
retval += " " + tokenImage[tok.kind];
retval += " \"";
retval += add_escapes(tok.image);
retval += " \"";
tok = tok.next;
}
retval += "\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn;
retval += "." + eol;
if (expectedTokenSequences.length == 1) {
retval += "Was expecting:" + eol + " ";
} else {
retval += "Was expecting one of:" + eol + " ";
}
retval += expected.toString();
return retval;
}
/**
* The end of line string for this machine.
*/
protected String eol = System.getProperty("line.separator", "\n");
/**
* Used to convert raw characters to their escaped version when these raw
* version cannot be used as part of an ASCII string literal.
*/
static String add_escapes(String str) {
StringBuffer retval = new StringBuffer();
char ch;
for (int i = 0; i < str.length(); i++) {
switch (str.charAt(i)) {
case 0:
continue;
case '\b':
retval.append("\\b");
continue;
case '\t':
retval.append("\\t");
continue;
case '\n':
retval.append("\\n");
continue;
case '\f':
retval.append("\\f");
continue;
case '\r':
retval.append("\\r");
continue;
case '\"':
retval.append("\\\"");
continue;
case '\'':
retval.append("\\\'");
continue;
case '\\':
retval.append("\\\\");
continue;
default:
if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
String s = "0000" + Integer.toString(ch, 16);
retval.append("\\u" + s.substring(s.length() - 4, s.length()));
} else {
retval.append(ch);
}
continue;
}
}
return retval.toString();
}
}