001// *************************************************************************************************************************** 002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * 003// * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * 004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * 005// * with the License. You may obtain a copy of the License at * 006// * * 007// * http://www.apache.org/licenses/LICENSE-2.0 * 008// * * 009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an * 010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the * 011// * specific language governing permissions and limitations under the License. * 012// *************************************************************************************************************************** 013package org.apache.juneau.svl.vars; 014 015import static org.apache.juneau.internal.ThrowableUtils.*; 016 017import java.util.regex.*; 018 019import org.apache.juneau.svl.*; 020 021/** 022 * A transformational variable resolver that returns character count or list count (using given delimiter). 023 * 024 * <p> 025 * The format for this var is one of the following: 026 * <ul> 027 * <li><js>"$LN{arg}"</js> 028 * <li><js>"$LN{arg, delimiter}"</js> 029 * </ul> 030 * 031 * <p> 032 * 033 * 034 * <h5 class='section'>Example:</h5> 035 * <p class='bcode w800'> 036 * <jc>// Create a variable resolver that resolves system properties and $SW vars.</jc> 037 * VarResolver r = VarResolver.<jsm>create</jsm>().vars(LenVar.<jk>class</jk>, SystemPropertiesVar.<jk>class</jk>).build(); 038 * 039 * <jc>// Use it!</jc> 040 * System.<jsf>out</jsf>.println(r.resolve(<js>"Parts = $LN{$P{os.version},.} Chars = $LN{$P{os.version}}"</js>)); 041 * </p> 042 * 043 * <p> 044 * Since this is a {@link MultipartVar}, any variables contained in the result will be recursively resolved. 045 * <br>Likewise, if the arguments contain any variables, those will be resolved before they are passed to this var. 046 * 047 * <h5 class='section'>See Also:</h5> 048 * <ul> 049 * <li class='link'>{@doc juneau-svl.SvlVariables} 050 * </ul> 051 */ 052public class LenVar extends MultipartVar { 053 054 /** The name of this variable. */ 055 public static final String NAME = "LN"; 056 057 /** 058 * Constructor. 059 */ 060 public LenVar() { 061 super(NAME); 062 } 063 064 @Override /* MultipartVar */ 065 public String resolve(VarResolverSession session, String[] args) { 066 if (args.length > 2) 067 illegalArg("Invalid number of arguments passed to $LN var. Must have 1 or 2 arguments."); 068 069 int len = 0; 070 String stringArg = args[0]; 071 if (args.length == 1) 072 len = stringArg.length(); 073 else if (args.length == 2) { 074 //delimiter is given 075 String delimiter = Pattern.quote(args[1]); 076 len = stringArg.trim().split(delimiter).length; 077 } 078 return String.valueOf(len); 079 } 080}