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/* * Copyright 2002-2016 the original author or authors. * * Licensed 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 * * https://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.springframework.core.env; import org.springframework.core.convert.support.ConfigurableConversionService; import org.springframework.lang.Nullable; /** * Configuration interface to be implemented by most if not all {@link PropertyResolver} * types. Provides facilities for accessing and customizing the * {@link org.springframework.core.convert.ConversionService ConversionService} * used when converting property values from one type to another. * * @author Chris Beams * @since 3.1 */ public interface ConfigurablePropertyResolver extends PropertyResolver { /** * Return the {@link ConfigurableConversionService} used when performing type * conversions on properties. * <p>The configurable nature of the returned conversion service allows for * the convenient addition and removal of individual {@code Converter} instances: * <pre class="code"> * ConfigurableConversionService cs = env.getConversionService(); * cs.addConverter(new FooConverter()); * </pre> * @see PropertyResolver#getProperty(String, Class) * @see org.springframework.core.convert.converter.ConverterRegistry#addConverter */ ConfigurableConversionService getConversionService(); /** * Set the {@link ConfigurableConversionService} to be used when performing type * conversions on properties. * <p><strong>Note:</strong> as an alternative to fully replacing the * {@code ConversionService}, consider adding or removing individual * {@code Converter} instances by drilling into {@link #getConversionService()} * and calling methods such as {@code #addConverter}. * @see PropertyResolver#getProperty(String, Class) * @see #getConversionService() * @see org.springframework.core.convert.converter.ConverterRegistry#addConverter */ void setConversionService(ConfigurableConversionService conversionService); /** * Set the prefix that placeholders replaced by this resolver must begin with. */ void setPlaceholderPrefix(String placeholderPrefix); /** * Set the suffix that placeholders replaced by this resolver must end with. */ void setPlaceholderSuffix(String placeholderSuffix); /** * Specify the separating character between the placeholders replaced by this * resolver and their associated default value, or {@code null} if no such * special character should be processed as a value separator. */ void setValueSeparator(@Nullable String valueSeparator); /** * Set whether to throw an exception when encountering an unresolvable placeholder * nested within the value of a given property. A {@code false} value indicates strict * resolution, i.e. that an exception will be thrown. A {@code true} value indicates * that unresolvable nested placeholders should be passed through in their unresolved * ${...} form. * <p>Implementations of {@link #getProperty(String)} and its variants must inspect * the value set here to determine correct behavior when property values contain * unresolvable placeholders. * @since 3.2 */ void setIgnoreUnresolvableNestedPlaceholders(boolean ignoreUnresolvableNestedPlaceholders); /** * Specify which properties must be present, to be verified by * {@link #validateRequiredProperties()}. */ void setRequiredProperties(String... requiredProperties); /** * Validate that each of the properties specified by * {@link #setRequiredProperties} is present and resolves to a * non-{@code null} value. * @throws MissingRequiredPropertiesException if any of the required * properties are not resolvable. */ void validateRequiredProperties() throws MissingRequiredPropertiesException; }