org.antlr.v4.runtime.atn.LexerChannelAction 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.Token;
import org.antlr.v4.runtime.misc.MurmurHash;
/**
* Implements the {@code channel} lexer action by calling
* {@link Lexer#setChannel} with the assigned channel.
*
* @author Sam Harwell
* @since 4.2
*/
public final class LexerChannelAction implements LexerAction {
private final int channel;
/**
* Constructs a new {@code channel} action with the specified channel value.
* @param channel The channel value to pass to {@link Lexer#setChannel}.
*/
public LexerChannelAction(int channel) {
this.channel = channel;
}
/**
* Gets the channel to use for the {@link Token} created by the lexer.
*
* @return The channel to use for the {@link Token} created by the lexer.
*/
public int getChannel() {
return channel;
}
/**
* {@inheritDoc}
* @return This method returns {@link LexerActionType#CHANNEL}.
*/
@Override
public LexerActionType getActionType() {
return LexerActionType.CHANNEL;
}
/**
* {@inheritDoc}
* @return This method returns {@code false}.
*/
@Override
public boolean isPositionDependent() {
return false;
}
/**
* {@inheritDoc}
*
* This action is implemented by calling {@link Lexer#setChannel} with the
* value provided by {@link #getChannel}.
*/
@Override
public void execute(Lexer lexer) {
lexer.setChannel(channel);
}
@Override
public int hashCode() {
int hash = MurmurHash.initialize();
hash = MurmurHash.update(hash, getActionType().ordinal());
hash = MurmurHash.update(hash, channel);
return MurmurHash.finish(hash, 2);
}
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
else if (!(obj instanceof LexerChannelAction)) {
return false;
}
return channel == ((LexerChannelAction)obj).channel;
}
@Override
public String toString() {
return String.format("channel(%d)", channel);
}
}