org.springframework.beans.factory.support.LookupOverride.java Source code

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Here is the source code for org.springframework.beans.factory.support.LookupOverride.java

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/*
 * Copyright 2002-2017 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.support;

import java.lang.reflect.Method;
import java.lang.reflect.Modifier;

import org.springframework.lang.Nullable;
import org.springframework.util.ObjectUtils;

/**
 * Represents an override of a method that looks up an object in the same IoC context.
 *
 * <p>Methods eligible for lookup override must not have arguments.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 1.1
 */
public class LookupOverride extends MethodOverride {

    @Nullable
    private final String beanName;

    @Nullable
    private Method method;

    /**
     * Construct a new LookupOverride.
     * @param methodName the name of the method to override
     * @param beanName the name of the bean in the current {@code BeanFactory}
     * that the overridden method should return (may be {@code null})
     */
    public LookupOverride(String methodName, @Nullable String beanName) {
        super(methodName);
        this.beanName = beanName;
    }

    /**
     * Construct a new LookupOverride.
     * @param method the method to override
     * @param beanName the name of the bean in the current {@code BeanFactory}
     * that the overridden method should return (may be {@code null})
     */
    public LookupOverride(Method method, @Nullable String beanName) {
        super(method.getName());
        this.method = method;
        this.beanName = beanName;
    }

    /**
     * Return the name of the bean that should be returned by this method.
     */
    @Nullable
    public String getBeanName() {
        return this.beanName;
    }

    /**
     * Match the specified method by {@link Method} reference or method name.
     * <p>For backwards compatibility reasons, in a scenario with overloaded
     * non-abstract methods of the given name, only the no-arg variant of a
     * method will be turned into a container-driven lookup method.
     * <p>In case of a provided {@link Method}, only straight matches will
     * be considered, usually demarcated by the {@code @Lookup} annotation.
     */
    @Override
    public boolean matches(Method method) {
        if (this.method != null) {
            return method.equals(this.method);
        } else {
            return (method.getName().equals(getMethodName()) && (!isOverloaded()
                    || Modifier.isAbstract(method.getModifiers()) || method.getParameterCount() == 0));
        }
    }

    @Override
    public boolean equals(@Nullable Object other) {
        if (!(other instanceof LookupOverride) || !super.equals(other)) {
            return false;
        }
        LookupOverride that = (LookupOverride) other;
        return (ObjectUtils.nullSafeEquals(this.method, that.method)
                && ObjectUtils.nullSafeEquals(this.beanName, that.beanName));
    }

    @Override
    public int hashCode() {
        return (29 * super.hashCode() + ObjectUtils.nullSafeHashCode(this.beanName));
    }

    @Override
    public String toString() {
        return "LookupOverride for method '" + getMethodName() + "'";
    }

}