io.activej.jmx.AbstractAttributeNodeForLeaf Maven / Gradle / Ivy

Go to download
/*
 * Copyright (C) 2020 ActiveJ LLC.
 *
 * 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 io.activej.jmx;

import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;

import static io.activej.common.Checks.checkArgument;
import static io.activej.common.Utils.first;
import static java.util.Collections.singleton;
import static java.util.Collections.singletonMap;

abstract class AbstractAttributeNodeForLeaf implements AttributeNode {
	protected final String name;
	private final String description;
	protected final ValueFetcher fetcher;
	private boolean visible;

	protected AbstractAttributeNodeForLeaf(String name, @Nullable String description, ValueFetcher fetcher, boolean visible) {
		this.name = name;
		this.description = description;
		this.fetcher = fetcher;
		this.visible = visible;
	}

	@Override
	public final String getName() {
		return name;
	}

	@Override
	public final Set getAllAttributes() {
		return singleton(name);
	}

	@Override
	public final Set getVisibleAttributes() {
		return visible ? singleton(name) : Collections.emptySet();
	}

	@Override
	public final Map> getDescriptions() {
		if (description != null) {
			return singletonMap(name, singletonMap(name, description));
		} else {
			return singletonMap(name, Collections.emptyMap());
		}
	}

	@Override
	public final Map aggregateAttributes(@NotNull Set attrNames, @NotNull List sources) {
		checkArgument(attrNames.size() == 1);
		String attrName = first(attrNames);
		checkArgument(name.equals(attrName));

		if (sources.isEmpty()) {
			return singletonMap(attrName, null);
		}

		return Collections.singletonMap(name, aggregateAttribute(attrName, sources));
	}

	/**
	 * It's guaranteed that list of sources is not empty, and it doesn't contain null values
	 *
	 * @param attrName name of attribute whose value return
	 * @param sources  attributes
	 * @return value of attribute with name attrName
	 */
	protected abstract Object aggregateAttribute(String attrName, List sources);

	@Override
	public final boolean isVisible() {
		return visible;
	}

	@Override
	public final void setVisible(@NotNull String attrName) {
		checkArgument(name.equals(attrName));
		this.visible = true;
	}

	@Override
	public final void hideNullPojos(@NotNull List sources) {
	}

	@Override
	public final void applyModifier(@NotNull String attrName, @NotNull AttributeModifier modifier, @NotNull List target) {
		checkArgument(name.equals(attrName));
		throw new UnsupportedOperationException(String.format(
				"AttributeModifier can be applied only to POJO. Attribute \"%s\" is not a POJO.", attrName
		));
	}
}