/*
* 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.
*/
package org.apache.wicket.resource;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.apache.wicket.css.ICssCompressor;
/**
* Used to apply several {@link ICssCompressor} to the CSS compression.<br>
* <br>
* Usage:
*
* <pre>
* CompositeCssCompressor compositeCssCompressor = new CompositeCssCompressor();
*
* compositeCssCompressor.add(new MyCssCompressor());
* compositeCssCompressor.add(new AnotherCssCompressor());
*
* this.getResourceSettings().setCssCompressor(compositeCssCompressor);
* </pre>
* The compressors can also be given as constructor arguments.
*
* @since 6.20.0
* @author Tobias Soloschenko
*/
public class CompositeCssCompressor implements IScopeAwareTextResourceProcessor, ICssCompressor
{
/* Compressors to compress the CSS content */
private final List<ICssCompressor> compressors = new ArrayList<>();
/**
* Initializes the composite CSS compressor with the given {@link ICssCompressor}(s)
*
* @param compressors
* The {@link ICssCompressor}(s) this composite CSS compressor is initialized with
*/
public CompositeCssCompressor(ICssCompressor... compressors)
{
this.compressors.addAll(Arrays.asList(compressors));
}
/**
* Compresses the given original content in the order of compressors. If no compressor has been
* given the original content is going to be returned.
*/
@Override
public String process(String input, Class<?> scope, String name)
{
String compressed = input;
for (ICssCompressor compressor : compressors)
{
if (compressor instanceof IScopeAwareTextResourceProcessor)
{
IScopeAwareTextResourceProcessor processor = (IScopeAwareTextResourceProcessor)compressor;
compressed = processor.process(compressed, scope, name);
}
else
{
compressed = compressor.compress(compressed);
}
}
return compressed;
}
@Override
public String compress(String original)
{
throw new UnsupportedOperationException(CompositeCssCompressor.class.getSimpleName() + ".process() should be used instead!");
}
/**
* Adds a ICssCompressor to the list of delegates.
*
* @return {@code this} instance, for chaining
*/
public CompositeCssCompressor add(ICssCompressor compressor)
{
compressors.add(compressor);
return this;
}
}