/*
* Copyright 2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* $Header:$
*/
package org.apache.beehive.netui.script.el.parser;
import org.apache.beehive.netui.util.internal.InternalStringBuilder;
public class TokenMgrError
extends Error {
/*
* Ordinals for various reasons why an Error of this type can be thrown.
*/
/**
* Lexical error occured.
*/
static final int LEXICAL_ERROR = 0;
/**
* An attempt wass made to create a second instance of a static token manager.
*/
static final int STATIC_LEXER_ERROR = 1;
/**
* Tried to change to an invalid lexical state.
*/
static final int INVALID_LEXICAL_STATE = 2;
/**
* Detected (and bailed out of) an infinite loop in the token manager.
*/
static final int LOOP_DETECTED = 3;
/**
* Indicates the reason why the exception is thrown. It will have
* one of the above 4 values.
*/
int errorCode;
/**
* Replaces unprintable characters by their espaced (or unicode escaped)
* equivalents in the given string
*/
protected static final String addEscapes(String str) {
InternalStringBuilder retval = new InternalStringBuilder();
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();
}
/**
* Returns a detailed message for the Error when it is thrown by the
* token manager to indicate a lexical error.
* Parameters :
* EOFSeen : indicates if EOF caused the lexicl error
* curLexState : lexical state in which this error occured
* errorLine : line number when the error occured
* errorColumn : column number when the error occured
* errorAfter : prefix that was seen before this error occured
* curchar : the offending character
* Note: You can customize the lexical error message by modifying this method.
*/
protected static String LexicalError(boolean EOFSeen, int lexState, int errorLine, int errorColumn, String errorAfter, char curChar) {
return ("Lexical error at line " +
errorLine + ", column " +
errorColumn + ". Encountered: " +
(EOFSeen ? "<EOF> " : ("\"" + addEscapes(String.valueOf(curChar)) + "\"") + " (" + (int)curChar + "), ") +
"after : \"" + addEscapes(errorAfter) + "\"");
}
/**
* You can also modify the body of this method to customize your error messages.
* For example, cases like LOOP_DETECTED and INVALID_LEXICAL_STATE are not
* of end-users concern, so you can return something like :
* <p/>
* "Internal Error : Please file a bug report .... "
* <p/>
* from this method for such cases in the release version of your parser.
*/
public String getMessage() {
return super.getMessage();
}
/*
* Constructors of various flavors follow.
*/
public TokenMgrError() {
}
public TokenMgrError(String message, int reason) {
super(message);
errorCode = reason;
}
public TokenMgrError(boolean EOFSeen, int lexState, int errorLine, int errorColumn, String errorAfter, char curChar, int reason) {
this(LexicalError(EOFSeen, lexState, errorLine, errorColumn, errorAfter, curChar), reason);
}
}