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The ANTLR 4 Runtime (Optimized)
/*
* Copyright (c) 2012 The ANTLR Project. All rights reserved.
* Use of this file is governed by the BSD-3-Clause license that
* can be found in the LICENSE.txt file in the project root.
*/
package org.antlr.v4.runtime;
import org.antlr.v4.runtime.misc.NotNull;
import org.antlr.v4.runtime.misc.Nullable;
/**
* This interface provides information about the vocabulary used by a
* recognizer.
*
* @see Recognizer#getVocabulary()
* @author Sam Harwell
*/
public interface Vocabulary {
/**
* Returns the highest token type value. It can be used to iterate from
* zero to that number, inclusively, thus querying all stored entries.
* @return the highest token type value
*/
int getMaxTokenType();
/**
* Gets the string literal associated with a token type. The string returned
* by this method, when not {@code null}, can be used unaltered in a parser
* grammar to represent this token type.
*
* The following table shows examples of lexer rules and the literal
* names assigned to the corresponding token types.
*
*
*
* Rule
* Literal Name
* Java String Literal
*
*
* {@code THIS : 'this';}
* {@code 'this'}
* {@code "'this'"}
*
*
* {@code SQUOTE : '\'';}
* {@code '\''}
* {@code "'\\''"}
*
*
* {@code ID : [A-Z]+;}
* n/a
* {@code null}
*
*
*
* @param tokenType The token type.
*
* @return The string literal associated with the specified token type, or
* {@code null} if no string literal is associated with the type.
*/
@Nullable
String getLiteralName(int tokenType);
/**
* Gets the symbolic name associated with a token type. The string returned
* by this method, when not {@code null}, can be used unaltered in a parser
* grammar to represent this token type.
*
* This method supports token types defined by any of the following
* methods:
*
*
* - Tokens created by lexer rules.
* - Tokens defined in a
tokens{} block in a lexer or parser
* grammar.
* - The implicitly defined {@code EOF} token, which has the token type
* {@link Token#EOF}.
*
*
* The following table shows examples of lexer rules and the literal
* names assigned to the corresponding token types.
*
*
*
* Rule
* Symbolic Name
*
*
* {@code THIS : 'this';}
* {@code THIS}
*
*
* {@code SQUOTE : '\'';}
* {@code SQUOTE}
*
*
* {@code ID : [A-Z]+;}
* {@code ID}
*
*
*
* @param tokenType The token type.
*
* @return The symbolic name associated with the specified token type, or
* {@code null} if no symbolic name is associated with the type.
*/
@Nullable
String getSymbolicName(int tokenType);
/**
* Gets the display name of a token type.
*
* ANTLR provides a default implementation of this method, but
* applications are free to override the behavior in any manner which makes
* sense for the application. The default implementation returns the first
* result from the following list which produces a non-{@code null}
* result.
*
*
* - The result of {@link #getLiteralName}
* - The result of {@link #getSymbolicName}
* - The result of {@link Integer#toString}
*
*
* @param tokenType The token type.
*
* @return The display name of the token type, for use in error reporting or
* other user-visible messages which reference specific token types.
*/
@NotNull
String getDisplayName(int tokenType);
}