/*
* JavaConstantsFile.java
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 3
* of the License, or (at your option) any later version.
*
* This library 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 library; if not, write to the Free
* Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307, USA.
*
* Copyright (c) 2003-2005 Per Cederberg. All rights reserved.
*/
package net.percederberg.grammatica.output;
import java.io.IOException;
import java.util.HashMap;
import net.percederberg.grammatica.code.java.JavaComment;
import net.percederberg.grammatica.code.java.JavaFile;
import net.percederberg.grammatica.code.java.JavaInterface;
import net.percederberg.grammatica.code.java.JavaVariable;
import net.percederberg.grammatica.parser.ProductionPattern;
import net.percederberg.grammatica.parser.TokenPattern;
/**
* The Java constants file generator. This class encapsulates all the
* Java code necessary for creating a constants interface file.
*
* @author Per Cederberg, <per at percederberg dot net>
* @version 1.0
*/
class JavaConstantsFile {
/**
* The interface comment.
*/
private static final String TYPE_COMMENT =
"An interface with constants for the parser and tokenizer.";
/**
* The token constant comment.
*/
private static final String TOKEN_COMMENT =
"A token identity constant.";
/**
* The production constant comment.
*/
private static final String PRODUCTION_COMMENT =
"A production node identity constant.";
/**
* The Java parser generator.
*/
private JavaParserGenerator gen;
/**
* The Java file to write.
*/
private JavaFile file;
/**
* The Java constants interface.
*/
private JavaInterface ifc;
/**
* The mapping from id to constant name. This map contains all
* tokens and productions added to the file.
*/
private HashMap constantNames = new HashMap();
/**
* Creates a new constants file.
*
* @param gen the parser generator to use
*/
public JavaConstantsFile(JavaParserGenerator gen) {
int modifiers;
this.gen = gen;
this.file = gen.createJavaFile();
if (gen.getPublicAccess()) {
modifiers = JavaInterface.PUBLIC;
} else {
modifiers = JavaInterface.PACKAGE_LOCAL;
}
this.ifc = new JavaInterface(modifiers,
gen.getBaseName() + "Constants");
initializeCode();
}
/**
* Initializes the source code objects.
*/
private void initializeCode() {
String str;
// Add interface
file.addInterface(ifc);
// Add file comment
str = file.toString() + "\n\n" + gen.getFileComment();
file.addComment(new JavaComment(JavaComment.BLOCK, str));
// Add interface comment
str = TYPE_COMMENT;
if (gen.getClassComment() != null) {
str += "\n\n" + gen.getClassComment();
}
ifc.addComment(new JavaComment(str));
}
/**
* Adds a token constant definition to this file.
*
* @param pattern the token pattern
*/
public void addToken(TokenPattern pattern) {
String constant;
JavaVariable var;
int modifiers;
constant = gen.getCodeStyle().getUpperCase(pattern.getName());
modifiers = JavaVariable.PUBLIC + JavaVariable.STATIC +
JavaVariable.FINAL;
var = new JavaVariable(modifiers,
"int",
constant,
"" + pattern.getId());
var.addComment(new JavaComment(TOKEN_COMMENT));
ifc.addVariable(var);
constantNames.put(new Integer(pattern.getId()), constant);
}
/**
* Adds a production constant definition to this file. This method
* checks if the production pattern has already been added.
*
* @param pattern the production pattern
*/
public void addProduction(ProductionPattern pattern) {
String constant;
JavaVariable var;
int modifiers;
if (!pattern.isSynthetic()) {
constant = gen.getCodeStyle().getUpperCase(pattern.getName());
modifiers = JavaVariable.PUBLIC + JavaVariable.STATIC +
JavaVariable.FINAL;
var = new JavaVariable(modifiers,
"int",
constant,
"" + pattern.getId());
var.addComment(new JavaComment(PRODUCTION_COMMENT));
ifc.addVariable(var);
constantNames.put(new Integer(pattern.getId()), constant);
}
}
/**
* Creates source code for accessing one of the constants in this
* file.
*
* @param id the node type (pattern) id
*
* @return the constant name, or
* null if not found
*/
public String getConstant(int id) {
String name = (String) constantNames.get(new Integer(id));
if (name == null) {
return null;
} else {
return ifc.toString() + "." + name;
}
}
/**
* Writes the file source code.
*
* @throws IOException if the output file couldn't be created
* correctly
*/
public void writeCode() throws IOException {
file.writeCode(gen.getCodeStyle());
}
}