2019-08-16 PropertySource类及其子类

PropertySource 类说明

/*
 * Copyright 2002-2014 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
 *
 *      http://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.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.util.Assert;
import org.springframework.util.ObjectUtils;
public abstract class PropertySource {
    protected final Log logger = LogFactory.getLog(getClass());
    protected final String name;
    protected final T source;
    public PropertySource(String name, T source) {
        Assert.hasText(name, "Property source name must contain at least one character");
        Assert.notNull(source, "Property source must not be null");
        this.name = name;
        this.source = source;
    }
    @SuppressWarnings("unchecked")
    public PropertySource(String name) {
        this(name, (T) new Object());
    }
    public String getName() {
        return this.name;
    }
    public T getSource() {
        return this.source;
    }
    public boolean containsProperty(String name) {
        return (getProperty(name) != null);
    }
    public abstract Object getProperty(String name);
    @Override
    public boolean equals(Object obj) {
        return (this == obj || (obj instanceof PropertySource &&
                ObjectUtils.nullSafeEquals(this.name, ((PropertySource) obj).name)));
    }
    @Override
    public int hashCode() {
        return ObjectUtils.nullSafeHashCode(this.name);
    }
    @Override
    public String toString() {
        if (logger.isDebugEnabled()) {
            return String.format("%s@%s [name='%s', properties=%s]",
                    getClass().getSimpleName(), System.identityHashCode(this), this.name, this.source);
        }
        else {
            return String.format("%s [name='%s']", getClass().getSimpleName(), this.name);
        }
    }
    public static PropertySource named(String name) {
        return new ComparisonPropertySource(name);
    }
    public static class StubPropertySource extends PropertySource