org.eclipse.ocl.lpg.AbstractLexer Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of ocl Show documentation
Show all versions of ocl Show documentation
OCL (Object Constraint Language) Parser and Interpreter
/**
*
*
* Copyright (c) 2005, 2010 IBM Corporation, Zeligsoft Inc., and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM - Initial API and implementation
* E.D.Willink - Lexer and Parser refactoring to support extensibility and flexible error handling
* - Bug 243976
* Zeligsoft - Bug 243976
*
*
*
* $Id: AbstractLexer.java,v 1.6 2010/05/03 09:32:32 ewillink Exp $
*/
package org.eclipse.ocl.lpg;
import java.io.IOException;
import java.io.Reader;
import lpg.runtime.ILexStream;
import lpg.runtime.LexParser;
import lpg.runtime.Monitor;
import lpg.runtime.ParseTable;
/**
* The AbstractLexer supports lexical analysis of keyword tokens produced by
* a keyword lexer to create syntactic tokens for an AbstractLexer that
* creates a corresponding CST, that may in turn be
* exploited by an AbstractAnalyzer to create an AST.
*
* Derived classes should extend the abstract support for AST from CST from tokens from text
* parsing and analysis to support the AST and CST classes appropriate to a particular language.
*/
public abstract class AbstractLexer
{
/**
* Read all input characters from a reader.
* @param reader providing the source text
* @return the input characters
* @throws IOException if reading fails
*/
public static char[] getInputChars(Reader reader) throws IOException {
char[] buffer = new char[16384];
int nextIndex = 0;
while (reader.ready()) {
if (nextIndex >= buffer.length) {
char[] newBuffer = new char[2 * buffer.length];
System.arraycopy(buffer, 0, newBuffer, 0, buffer.length);
buffer = newBuffer;
}
int moreChars = reader.read(buffer, nextIndex, buffer.length - nextIndex);
if (moreChars > 0)
nextIndex += moreChars;
else if (moreChars < 0)
break;
}
if (nextIndex != buffer.length) {
char[] newBuffer = new char[nextIndex];
System.arraycopy(buffer, 0, newBuffer, 0, nextIndex);
buffer = newBuffer;
}
return buffer;
}
private final BasicEnvironment environment;
public AbstractLexer(BasicEnvironment environment)
{
this.environment = environment;
}
public BasicEnvironment getEnvironment() {
return environment;
}
/**
* Define the input text as a given array of characters.
* @param inputChars the characters
* @deprecated clients should use {@link #reset(char[], String)}
*/
@Deprecated
public void initialize(char[] inputChars) {
reset(inputChars, null);
}
/**
* Define the input text by reading from a reader.
* @param reader providing the source text
* @throws IOException if reading fails
*
* @deprecated clients should invoke {@link #reset(Reader, String)}
*/
@Deprecated
public void initialize(Reader reader) throws IOException {
char[] buffer = getInputChars(reader);
reset(buffer, null);
}
/**
* @param parser the {@link AbstractParser} instance
* @deprecated clients should invoke {@link #lexer(DerivedPrsStream)}
*/
@Deprecated
public void lexToTokens(AbstractParser parser) {
lexToTokens(null, parser);
}
/**
* @param parser the {@link AbstractParser} instance
* @deprecated clients should invoke {@link #lexer(Monitor, DerivedPrsStream)}
*/
@Deprecated
public void lexToTokens(Monitor monitor, AbstractParser parser) {
lexer(monitor, parser.getIPrsStream());
}
// Some methods which will be implemented by the generated lexer
/**
* Queries the token kinds, as defined by my keyword lexer, of tokens that
* are keywords in by grammar.
*
* @return my keyword lexer's token kinds
*
* @since 1.3
*/
public abstract int [] getKeywordKinds();
/**
* @return the lexers's {@link ILexStream lexStream}
*
* @since 3.0
*/
public abstract DerivedLexStream getILexStream();
/**
* Resets the lexer's input with the given char's array.
*
* @param input_chars the new lexer's input
* @param filename a file name used for logging when encountering errors/warnings
*
* @since 3.0
*/
public abstract void reset(char[] input_chars, String filename);
/**
* Resets the lexer's input with the given char's array.
*
* @param input_chars the new lexer's input
* @param filename a file name used for logging when encountering errors/warnings
* @param tab lexer's tab length.
*
* @since 3.0
*/
public abstract void reset(char[] input_chars, String filename, int tab);
/**
* Resets the lexer's input with the given Reader
*
* @param reader the new lexer's input
* @param filename a file name used for logging when encountering errors/warnings
* @throws java.io.IOException
*
* @since 3.0
*/
public abstract void reset(Reader reader, String filename) throws java.io.IOException;
/**
* Runs the lexer's with the provided {@link DerivedPrsStream parseStream}
*
* @param prsStream the associated {@link DerivedPrsStream parseStream}
* @since 3.0
*/
public abstract void lexer(DerivedPrsStream prsStream);
/**
* Runs the lexer's with the provided {@link DerivedPrsStream parseStream} and
* the given monitor.
*
* @param monitor the {@link Monitor}
* @param prsStream the associated {@link DerivedPrsStream parseStream}
*
* @since 3.0
*/
public abstract void lexer(Monitor monitor, DerivedPrsStream prsStream);
/**
* Runs the lexer's with the provided {@link DerivedPrsStream parseStream}
* in specific offset of the input
*
* @param prsStream the associated {@link DerivedPrsStream parseStream}
* @param start_offset the start offset
* @param end_offset the end offset
*
* @since 3.0
*/
public abstract void lexer(DerivedPrsStream prsStream, int start_offset, int end_offset);
/**
* Runs the lexer's with the provided {@link DerivedPrsStream parseStream}
* in specific offset of the input
*
* @param prsStream the associated {@link DerivedPrsStream parseStream}
* @param start_offset the start offset
* @param end_offset the end offset
*
* @since 3.0
*/
public abstract void lexer(Monitor monitor, DerivedPrsStream prsStream, int start_offset, int end_offset);
/**
* @return the lexer's {@link ParseTable}
* @since 3.0
*/
public abstract ParseTable getParseTable();
/**
* @return the lexer's {@link LexParser}
* @since 3.0
*/
public abstract LexParser getParser();
/**
* Rsets the lexer's keywordLexer
* @since 3.0
*/
public abstract void resetKeywordLexer();
/**
* @return the lexer's {@link ILexStream lexStream}
* @since 3.0
*/
public abstract ILexStream getLexStream();
/**
* Report a lexical error in the given localization (start and end offset)
*
* @param startLoc the offset the error starts
* @param endLoc the offset the error ends.
*
* @since 3.0
*/
public abstract void reportLexicalError(int startLoc, int endLoc);
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy