org.springframework.core.AttributeAccessorSupport Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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;
import java.io.Serializable;
import java.util.LinkedHashMap;
import java.util.Map;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* Support class for {@link AttributeAccessor AttributeAccessors}, providing
* a base implementation of all methods. To be extended by subclasses.
*
* {@link Serializable} if subclasses and all attribute values are {@link Serializable}.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @since 2.0
*/
@SuppressWarnings("serial")
public abstract class AttributeAccessorSupport implements AttributeAccessor, Serializable {
/** Map with String keys and Object values. */
private final Map attributes = new LinkedHashMap<>();
@Override
public void setAttribute(String name, @Nullable Object value) {
Assert.notNull(name, "Name must not be null");
if (value != null) {
this.attributes.put(name, value);
}
else {
removeAttribute(name);
}
}
@Override
@Nullable
public Object getAttribute(String name) {
Assert.notNull(name, "Name must not be null");
return this.attributes.get(name);
}
@Override
@Nullable
public Object removeAttribute(String name) {
Assert.notNull(name, "Name must not be null");
return this.attributes.remove(name);
}
@Override
public boolean hasAttribute(String name) {
Assert.notNull(name, "Name must not be null");
return this.attributes.containsKey(name);
}
@Override
public String[] attributeNames() {
return StringUtils.toStringArray(this.attributes.keySet());
}
/**
* Copy the attributes from the supplied AttributeAccessor to this accessor.
* @param source the AttributeAccessor to copy from
*/
protected void copyAttributesFrom(AttributeAccessor source) {
Assert.notNull(source, "Source must not be null");
String[] attributeNames = source.attributeNames();
for (String attributeName : attributeNames) {
setAttribute(attributeName, source.getAttribute(attributeName));
}
}
@Override
public boolean equals(Object other) {
return (this == other || (other instanceof AttributeAccessorSupport &&
this.attributes.equals(((AttributeAccessorSupport) other).attributes)));
}
@Override
public int hashCode() {
return this.attributes.hashCode();
}
}