ServerController.java

/*
 * Copyright 2013 David Tinker
 *
 * 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.qdb.server.controller;

import humanize.Humanize;

import javax.inject.Inject;
import javax.inject.Singleton;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.lang.management.MemoryUsage;

@Singleton
public class ServerController extends CrudController {

    private final long started = System.currentTimeMillis();

    public static class StatusDTO {
        public String uptime;
        public String qdbVersion;
        public long heapFreeMemory;
        public long heapMaxMemory;
        public long otherFreeMemory;
        public long otherMaxMemory;
    }

    @Inject
    public ServerController(JsonService jsonService) {
        super(jsonService);
    }

    @Override
    protected void list(Call call, int offset, int limit) throws IOException {
        StatusDTO dto = new StatusDTO();

        int secs = (int)((System.currentTimeMillis() - started) / 1000);
        int days = secs / (24 * 60 * 60);
        secs %= 24 * 60 * 60;
        dto.uptime = (days == 1 ? "1 day " : days > 0 ? days + " days " : "") + Humanize.duration(secs);

        dto.qdbVersion = Package.getPackage("io.qdb.server").getImplementationVersion();

        if (call.getBoolean("gc")) System.gc();
        dto.heapMaxMemory = Runtime.getRuntime().totalMemory();
        dto.heapFreeMemory = Runtime.getRuntime().freeMemory();

        MemoryUsage usage = ManagementFactory.getMemoryMXBean().getNonHeapMemoryUsage();
        dto.otherMaxMemory = usage.getMax();
        dto.otherFreeMemory = dto.otherMaxMemory - usage.getUsed();

        call.setJson(dto);
    }
}