com.google.code.yanf4j.util.SystemUtils Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of xmemcached Show documentation
Extreme performance modern memcached client for java
There is a newer version: 2.4.8
/**
 * Copyright [2009-2010] [dennis zhuang([email protected])] 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
 */
/**
 * Copyright [2009-2010] [dennis zhuang([email protected])] 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 com.google.code.yanf4j.util;

import java.io.IOException;
import java.lang.reflect.Method;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.nio.channels.Selector;
import java.nio.channels.spi.SelectorProvider;
import java.util.Queue;
import java.util.Random;

/**
 * System utils
 * 
 * @author dennis
 * 
 */
public final class SystemUtils {

  private SystemUtils() {

  }

  public static final String OS_NAME = System.getProperty("os.name");

  private static boolean isLinuxPlatform = false;

  static {
    if (OS_NAME != null && OS_NAME.toLowerCase().indexOf("linux") >= 0) {
      isLinuxPlatform = true;
    }
  }
  public static final String JAVA_VERSION = System.getProperty("java.version");
  private static boolean isAfterJava6u4Version = false;
  static {
    if (JAVA_VERSION != null) {
      // java4 or java5
      if (JAVA_VERSION.indexOf("1.4.") >= 0 || JAVA_VERSION.indexOf("1.5.") >= 0) {
        isAfterJava6u4Version = false;
      } else if (JAVA_VERSION.indexOf("1.6.") >= 0) {
        int index = JAVA_VERSION.indexOf("_");
        if (index > 0) {
          String subVersionStr = JAVA_VERSION.substring(index + 1);
          if (subVersionStr != null && subVersionStr.length() > 0) {
            try {
              int subVersion = Integer.parseInt(subVersionStr);
              if (subVersion >= 4) {
                isAfterJava6u4Version = true;
              }
            } catch (NumberFormatException e) {

            }
          }
        }
        // after java6
      } else {
        isAfterJava6u4Version = true;
      }
    }
  }

  public static final boolean isLinuxPlatform() {
    return isLinuxPlatform;
  }

  public static final boolean isAfterJava6u4Version() {
    return isAfterJava6u4Version;
  }

  public static void main(String[] args) {
    System.out.println(isAfterJava6u4Version());
  }

  public static final int getSystemThreadCount() {
    int cpus = getCpuProcessorCount();
    if (cpus <= 8) {
      return cpus;
    } else {
      return 8 + (cpus - 8) * 5 / 8;
    }
  }

  public static final int getCpuProcessorCount() {
    return Runtime.getRuntime().availableProcessors();
  }

  public static final Selector openSelector() throws IOException {
    Selector result = null;
    // check if it is linux os
    if (SystemUtils.isLinuxPlatform()) {
      try {
        Class providerClazz = Class.forName("sun.nio.ch.EPollSelectorProvider");
        if (providerClazz != null) {
          try {
            Method method = providerClazz.getMethod("provider");
            if (method != null) {
              SelectorProvider selectorProvider = (SelectorProvider) method.invoke(null);
              if (selectorProvider != null) {
                result = selectorProvider.openSelector();
              }
            }
          } catch (Exception e) {
            // ignore
          }
        }
      } catch (Exception e) {
        // ignore
      }
    }
    if (result == null) {
      result = Selector.open();
    }
    return result;

  }

  public static final String getRawAddress(InetSocketAddress inetSocketAddress) {
    InetAddress address = inetSocketAddress.getAddress();
    return address != null ? address.getHostAddress() : inetSocketAddress.getHostName();
  }

  public static final Queue createTransferQueue() {
    try {
      return (Queue) Class.forName("java.util.concurrent.LinkedTransferQueue").newInstance();
    } catch (Exception e) {
      return new LinkedTransferQueue