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 org.apache.juneau.svl.*; 016 017/** 018 * A basic variable resolver that returns the first non-null value. 019 * 020 * <p> 021 * The format for this var is <js>"$CO{arg1[,arg2...]}"</js>. 022 * 023 * 024 * <ul class='seealso'> 025 * <li class='link'>{@doc SvlVariables} 026 * </ul> 027 */ 028public class CoalesceVar extends MultipartResolvingVar { 029 030 /** The name of this variable. */ 031 public static final String NAME = "CO"; 032 033 /** 034 * Constructor. 035 */ 036 public CoalesceVar() { 037 super(NAME); 038 } 039 040 @Override 041 public String resolve(VarResolverSession session, String arg) throws Exception { 042 return arg; 043 } 044}