org.antlr.v4.runtime.atn.LexerModeAction Maven / Gradle / Ivy
/*
* Copyright (c) 2012-2017 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.atn;
import org.antlr.v4.runtime.Lexer;
import org.antlr.v4.runtime.misc.MurmurHash;
/**
* Implements the {@code mode} lexer action by calling {@link Lexer#mode} with
* the assigned mode.
*
* @author Sam Harwell
* @since 4.2
*/
public final class LexerModeAction implements LexerAction {
private final int mode;
/**
* Constructs a new {@code mode} action with the specified mode value.
* @param mode The mode value to pass to {@link Lexer#mode}.
*/
public LexerModeAction(int mode) {
this.mode = mode;
}
/**
* Get the lexer mode this action should transition the lexer to.
*
* @return The lexer mode for this {@code mode} command.
*/
public int getMode() {
return mode;
}
/**
* {@inheritDoc}
* @return This method returns {@link LexerActionType#MODE}.
*/
@Override
public LexerActionType getActionType() {
return LexerActionType.MODE;
}
/**
* {@inheritDoc}
* @return This method returns {@code false}.
*/
@Override
public boolean isPositionDependent() {
return false;
}
/**
* {@inheritDoc}
*
* This action is implemented by calling {@link Lexer#mode} with the
* value provided by {@link #getMode}.
*/
@Override
public void execute(Lexer lexer) {
lexer.mode(mode);
}
@Override
public int hashCode() {
int hash = MurmurHash.initialize();
hash = MurmurHash.update(hash, getActionType().ordinal());
hash = MurmurHash.update(hash, mode);
return MurmurHash.finish(hash, 2);
}
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
else if (!(obj instanceof LexerModeAction)) {
return false;
}
return mode == ((LexerModeAction)obj).mode;
}
@Override
public String toString() {
return String.format("mode(%d)", mode);
}
}