org.apache.velocity.runtime.directive.Stop Maven / Gradle / Ivy
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package org.apache.velocity.runtime.directive;
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
import org.apache.velocity.context.InternalContextAdapter;
import org.apache.velocity.runtime.RuntimeServices;
import org.apache.velocity.runtime.parser.ParseException;
import org.apache.velocity.runtime.parser.Token;
import org.apache.velocity.runtime.parser.node.Node;
import java.io.Writer;
import java.util.ArrayList;
/**
* This class implements the #stop directive which allows
* a user to stop the merging and rendering process. The #stop directive
* will accept a single message argument with info about the reason for
* stopping.
*/
public class Stop extends Directive
{
private static final StopCommand STOP_ALL = new StopCommand("StopCommand to exit merging") {
@Override
public synchronized Throwable fillInStackTrace() {
return this;
}
};
private boolean hasMessage = false;
/**
* Return name of this directive.
* @return The name of this directive.
*/
@Override
public String getName()
{
return "stop";
}
/**
* Return type of this directive.
* @return The type of this directive.
*/
@Override
public int getType()
{
return LINE;
}
/**
* Since there is no processing of content,
* there is never a need for an internal scope.
*/
@Override
public boolean isScopeProvided()
{
return false;
}
@Override
public void init(RuntimeServices rs, InternalContextAdapter context, Node node)
{
super.init(rs, context, node);
hasMessage = (node.jjtGetNumChildren() == 1);
}
@Override
public boolean render(InternalContextAdapter context, Writer writer, Node node)
{
if (!hasMessage)
{
throw STOP_ALL;
}
Object argument = node.jjtGetChild(0).value(context);
// stop all and use specified message
throw new StopCommand(String.valueOf(argument));
}
/**
* Called by the parser to check the argument types
*/
@Override
public void checkArgs(ArrayList argtypes, Token t, String templateName)
throws ParseException
{
int kids = argtypes.size();
if (kids > 1)
{
throw new MacroParseException("The #stop directive only accepts a single message parameter",
templateName, t);
}
}
}