001/* 002 * Copyright 2012-2018 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.boot.autoconfigure.condition; 018 019import java.util.List; 020import java.util.function.Supplier; 021 022import org.springframework.boot.context.properties.bind.BindResult; 023import org.springframework.boot.context.properties.bind.Bindable; 024import org.springframework.boot.context.properties.bind.Binder; 025import org.springframework.context.annotation.Condition; 026import org.springframework.context.annotation.ConditionContext; 027import org.springframework.core.type.AnnotatedTypeMetadata; 028 029/** 030 * {@link Condition} that checks if a property whose value is a list is defined in the 031 * environment. 032 * 033 * @author Eneias Silva 034 * @author Stephane Nicoll 035 * @since 2.0.5 036 */ 037public class OnPropertyListCondition extends SpringBootCondition { 038 039 private static final Bindable<List<String>> STRING_LIST = Bindable 040 .listOf(String.class); 041 042 private final String propertyName; 043 044 private final Supplier<ConditionMessage.Builder> messageBuilder; 045 046 /** 047 * Create a new instance with the property to check and the message builder to use. 048 * @param propertyName the name of the property 049 * @param messageBuilder a message builder supplier that should provide a fresh 050 * instance on each call 051 */ 052 protected OnPropertyListCondition(String propertyName, 053 Supplier<ConditionMessage.Builder> messageBuilder) { 054 this.propertyName = propertyName; 055 this.messageBuilder = messageBuilder; 056 } 057 058 @Override 059 public ConditionOutcome getMatchOutcome(ConditionContext context, 060 AnnotatedTypeMetadata metadata) { 061 BindResult<?> property = Binder.get(context.getEnvironment()) 062 .bind(this.propertyName, STRING_LIST); 063 ConditionMessage.Builder messageBuilder = this.messageBuilder.get(); 064 if (property.isBound()) { 065 return ConditionOutcome 066 .match(messageBuilder.found("property").items(this.propertyName)); 067 } 068 return ConditionOutcome 069 .noMatch(messageBuilder.didNotFind("property").items(this.propertyName)); 070 } 071 072}