/*
* 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.util.parse.metapattern.parsers;
import java.util.ArrayList;
import java.util.List;
import org.apache.wicket.util.parse.metapattern.Group;
import org.apache.wicket.util.parse.metapattern.MetaPattern;
/**
* Parses an arbitrary list format with a pattern for list entries and a pattern for list
* separators.
*
* @author Jonathan Locke
*/
public class ListParser extends MetaPatternParser
{
/** The pattern in between the separators */
private final Group entryGroup;
/** The separator */
private final MetaPattern separatorPattern;
/** The list elements parsed */
private final List<String> values = new ArrayList<>();
/**
* Constructs a list parser from an entry MetaPattern, a separator MetaPattern and an input
* character sequence.
*
* @param entryPattern
* The pattern in between the separators
* @param separatorPattern
* The separator pattern
* @param input
* The input to parse
*/
public ListParser(final MetaPattern entryPattern, final MetaPattern separatorPattern,
final CharSequence input)
{
super(input);
entryGroup = new Group(entryPattern);
this.separatorPattern = separatorPattern;
}
/**
* Parse the input and add the elements to an internal list to be accessed by
*
* @see #getValues()
* @see org.apache.wicket.util.parse.metapattern.parsers.MetaPatternParser#matches()
*/
@Override
public final boolean matches()
{
// Are there any more elements
if (advance(entryGroup))
{
// Add the first element
final String value = entryGroup.get(matcher());
values.add(value);
// All remaining elements must be preceded by the separator pattern
while (advance(separatorPattern) && advance(entryGroup))
{
// Add the value not including the separator
values.add(entryGroup.get(matcher()));
}
// Yes, we found at least on element
return true;
}
// Nothing found, not even one element without separator
return false;
}
/**
* Gets the parsed values. It depends on the elements pattern, whether empty elements, double or
* single quotes or escape characters are supported.
*
* @return the parsed values
*/
public final List<String> getValues()
{
return values;
}
}