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/* * Copyright 2002-2019 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.beans.factory.config; import org.springframework.beans.BeanMetadataElement; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.ClassUtils; import org.springframework.util.ObjectUtils; /** * Holder for a typed String value. Can be added to bean definitions * in order to explicitly specify a target type for a String value, * for example for collection elements. * * <p>This holder will just store the String value and the target type. * The actual conversion will be performed by the bean factory. * * @author Juergen Hoeller * @since 1.2 * @see BeanDefinition#getPropertyValues * @see org.springframework.beans.MutablePropertyValues#addPropertyValue */ public class TypedStringValue implements BeanMetadataElement { @Nullable private String value; @Nullable private volatile Object targetType; @Nullable private Object source; @Nullable private String specifiedTypeName; private volatile boolean dynamic; /** * Create a new {@link TypedStringValue} for the given String value. * @param value the String value */ public TypedStringValue(@Nullable String value) { setValue(value); } /** * Create a new {@link TypedStringValue} for the given String value * and target type. * @param value the String value * @param targetType the type to convert to */ public TypedStringValue(@Nullable String value, Class<?> targetType) { setValue(value); setTargetType(targetType); } /** * Create a new {@link TypedStringValue} for the given String value * and target type. * @param value the String value * @param targetTypeName the type to convert to */ public TypedStringValue(@Nullable String value, String targetTypeName) { setValue(value); setTargetTypeName(targetTypeName); } /** * Set the String value. * <p>Only necessary for manipulating a registered value, * for example in BeanFactoryPostProcessors. */ public void setValue(@Nullable String value) { this.value = value; } /** * Return the String value. */ @Nullable public String getValue() { return this.value; } /** * Set the type to convert to. * <p>Only necessary for manipulating a registered value, * for example in BeanFactoryPostProcessors. */ public void setTargetType(Class<?> targetType) { Assert.notNull(targetType, "'targetType' must not be null"); this.targetType = targetType; } /** * Return the type to convert to. */ public Class<?> getTargetType() { Object targetTypeValue = this.targetType; if (!(targetTypeValue instanceof Class)) { throw new IllegalStateException("Typed String value does not carry a resolved target type"); } return (Class<?>) targetTypeValue; } /** * Specify the type to convert to. */ public void setTargetTypeName(@Nullable String targetTypeName) { this.targetType = targetTypeName; } /** * Return the type to convert to. */ @Nullable public String getTargetTypeName() { Object targetTypeValue = this.targetType; if (targetTypeValue instanceof Class) { return ((Class<?>) targetTypeValue).getName(); } else { return (String) targetTypeValue; } } /** * Return whether this typed String value carries a target type . */ public boolean hasTargetType() { return (this.targetType instanceof Class); } /** * Determine the type to convert to, resolving it from a specified class name * if necessary. Will also reload a specified Class from its name when called * with the target type already resolved. * @param classLoader the ClassLoader to use for resolving a (potential) class name * @return the resolved type to convert to * @throws ClassNotFoundException if the type cannot be resolved */ @Nullable public Class<?> resolveTargetType(@Nullable ClassLoader classLoader) throws ClassNotFoundException { String typeName = getTargetTypeName(); if (typeName == null) { return null; } Class<?> resolvedClass = ClassUtils.forName(typeName, classLoader); this.targetType = resolvedClass; return resolvedClass; } /** * Set the configuration source {@code Object} for this metadata element. * <p>The exact type of the object will depend on the configuration mechanism used. */ public void setSource(@Nullable Object source) { this.source = source; } @Override @Nullable public Object getSource() { return this.source; } /** * Set the type name as actually specified for this particular value, if any. */ public void setSpecifiedTypeName(@Nullable String specifiedTypeName) { this.specifiedTypeName = specifiedTypeName; } /** * Return the type name as actually specified for this particular value, if any. */ @Nullable public String getSpecifiedTypeName() { return this.specifiedTypeName; } /** * Mark this value as dynamic, i.e. as containing an expression * and hence not being subject to caching. */ public void setDynamic() { this.dynamic = true; } /** * Return whether this value has been marked as dynamic. */ public boolean isDynamic() { return this.dynamic; } @Override public boolean equals(@Nullable Object other) { if (this == other) { return true; } if (!(other instanceof TypedStringValue)) { return false; } TypedStringValue otherValue = (TypedStringValue) other; return (ObjectUtils.nullSafeEquals(this.value, otherValue.value) && ObjectUtils.nullSafeEquals(this.targetType, otherValue.targetType)); } @Override public int hashCode() { return ObjectUtils.nullSafeHashCode(this.value) * 29 + ObjectUtils.nullSafeHashCode(this.targetType); } @Override public String toString() { return "TypedStringValue: value [" + this.value + "], target type [" + this.targetType + "]"; } }