com.google.escapevelocity.StopNode Maven / Gradle / Ivy
/*
* Copyright (C) 2018 Google, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.google.escapevelocity;
/**
* A parsing node that represents the end of a span, such as the {@code #end} after the body of a
* {@code #foreach} or an {@code #else} in an {@code #if}. The end of the file is also one of these.
*
* These nodes are used during parsing but do not end up in the final parse tree.
*
* @author [email protected] (Éamonn McManus)
*/
abstract class StopNode extends Node {
StopNode(String resourceName, int lineNumber) {
super(resourceName, lineNumber);
}
/**
* This method always throws an exception because a node like this should never be found in the
* final parse tree.
*/
@Override
void render(EvaluationContext context, StringBuilder output) {
throw new UnsupportedOperationException(getClass().getName());
}
/**
* The name of the token, for use in parse error messages.
*/
abstract String name();
/**
* A synthetic node that represents the end of the input. This node is the last one in the
* initial token string and also the last one in the parse tree.
*/
static final class EofNode extends StopNode {
EofNode(String resourceName, int lineNumber) {
super(resourceName, lineNumber);
}
@Override
String name() {
return "end of file";
}
}
static final class EndNode extends StopNode {
EndNode(String resourceName, int lineNumber) {
super(resourceName, lineNumber);
}
@Override String name() {
return "#end";
}
}
static final class ElseIfNode extends StopNode {
ElseIfNode(String resourceName, int lineNumber) {
super(resourceName, lineNumber);
}
@Override String name() {
return "#elseif";
}
}
static final class ElseNode extends StopNode {
ElseNode(String resourceName, int lineNumber) {
super(resourceName, lineNumber);
}
@Override String name() {
return "#else";
}
}
}