001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.wicket.util.parse.metapattern.parsers; 018 019 020import java.util.ArrayList; 021import java.util.List; 022 023import org.apache.wicket.util.parse.metapattern.Group; 024import org.apache.wicket.util.parse.metapattern.MetaPattern; 025 026 027/** 028 * Parses an arbitrary list format with a pattern for list entries and a pattern for list 029 * separators. 030 * 031 * @author Jonathan Locke 032 */ 033public class ListParser extends MetaPatternParser 034{ 035 /** The pattern in between the separators */ 036 private final Group entryGroup; 037 038 /** The separator */ 039 private final MetaPattern separatorPattern; 040 041 /** The list elements parsed */ 042 private final List<String> values = new ArrayList<>(); 043 044 /** 045 * Constructs a list parser from an entry MetaPattern, a separator MetaPattern and an input 046 * character sequence. 047 * 048 * @param entryPattern 049 * The pattern in between the separators 050 * @param separatorPattern 051 * The separator pattern 052 * @param input 053 * The input to parse 054 */ 055 public ListParser(final MetaPattern entryPattern, final MetaPattern separatorPattern, 056 final CharSequence input) 057 { 058 super(input); 059 entryGroup = new Group(entryPattern); 060 this.separatorPattern = separatorPattern; 061 } 062 063 /** 064 * Parse the input and add the elements to an internal list to be accessed by 065 * 066 * @see #getValues() 067 * @see org.apache.wicket.util.parse.metapattern.parsers.MetaPatternParser#matches() 068 */ 069 @Override 070 public final boolean matches() 071 { 072 // Are there any more elements 073 if (advance(entryGroup)) 074 { 075 // Add the first element 076 final String value = entryGroup.get(matcher()); 077 values.add(value); 078 079 // All remaining elements must be preceded by the separator pattern 080 while (advance(separatorPattern) && advance(entryGroup)) 081 { 082 // Add the value not including the separator 083 values.add(entryGroup.get(matcher())); 084 } 085 086 // Yes, we found at least on element 087 return true; 088 } 089 090 // Nothing found, not even one element without separator 091 return false; 092 } 093 094 /** 095 * Gets the parsed values. It depends on the elements pattern, whether empty elements, double or 096 * single quotes or escape characters are supported. 097 * 098 * @return the parsed values 099 */ 100 public final List<String> getValues() 101 { 102 return values; 103 } 104}