一、前言

关于directmemory-common-0.2.jar源码包中org.apache.directmemory.conf.Configuration配置设计实现，如下图所示

二、源码说明

1.Configuration配置

package org.apache.directmemory.conf;@b@@b@import org.slf4j.Logger;@b@import org.slf4j.LoggerFactory;@b@@b@public final class Configuration@b@{@b@  private static final Logger logger = LoggerFactory.getLogger(Configuration.class);@b@  private static ConfigurationService configurationService;@b@@b@  public static int getNumberOfBuffers()@b@  {@b@    return configurationService.getNumberOfBuffers();@b@  }@b@@b@  public static int getInitialCapacity()@b@  {@b@    return configurationService.getInitialCapacity();@b@  }@b@@b@  public static int getRamMegaBytes()@b@  {@b@    return configurationService.getRamMegaBytes();@b@  }@b@@b@  public static long getDisposalTime()@b@  {@b@    return configurationService.getDisposalTime();@b@  }@b@@b@  public static int getConcurrencyLevel()@b@  {@b@    return configurationService.getConcurrencyLevel();@b@  }@b@@b@  public static void configureFromYaml()@b@  {@b@    logger.info("using yaml configuration implementation");@b@    configurationService = YamlConfiguration.load();@b@  }@b@@b@  static@b@  {@b@    if (configurationService == null)@b@    {@b@      logger.info("using default configuration implementation");@b@      configurationService = new SimplePropertiesConfiguration();@b@    }@b@  }@b@}

2.ConfigurationService接口

package org.apache.directmemory.conf;@b@@b@public abstract interface ConfigurationService@b@{@b@  public abstract int getNumberOfBuffers();@b@@b@  public abstract int getInitialCapacity();@b@@b@  public abstract int getRamMegaBytes();@b@@b@  public abstract int getConcurrencyLevel();@b@@b@  public abstract long getDisposalTime();@b@@b@  public abstract void setNumberOfBuffers(int paramInt);@b@@b@  public abstract void setInitialCapacity(int paramInt);@b@@b@  public abstract void setRamMegaBytes(int paramInt);@b@@b@  public abstract void setConcurrencyLevel(int paramInt);@b@@b@  public abstract void setDisposalTime(long paramLong);@b@}

3.DefaultConfiguration默认配置实现类

package org.apache.directmemory.conf;@b@@b@public abstract class DefaultConfiguration@b@  implements ConfigurationService@b@{@b@  private int numberOfBuffers;@b@  private int initialCapacity;@b@  private int ramMegaBytes;@b@  private int concurrencyLevel;@b@  private long disposalTime;@b@@b@  public DefaultConfiguration()@b@  {@b@    this.numberOfBuffers = 1;@b@@b@    this.initialCapacity = 100000;@b@@b@    this.ramMegaBytes = 1;@b@@b@    this.concurrencyLevel = 4;@b@@b@    this.disposalTime = 10L;@b@  }@b@@b@  public int getNumberOfBuffers()@b@  {@b@    return this.numberOfBuffers;@b@  }@b@@b@  public int getInitialCapacity()@b@  {@b@    return this.initialCapacity;@b@  }@b@@b@  public int getRamMegaBytes()@b@  {@b@    return this.ramMegaBytes;@b@  }@b@@b@  public int getConcurrencyLevel()@b@  {@b@    return this.concurrencyLevel;@b@  }@b@@b@  public long getDisposalTime()@b@  {@b@    return this.disposalTime;@b@  }@b@@b@  public void setNumberOfBuffers(int numberOfBuffers)@b@  {@b@    this.numberOfBuffers = numberOfBuffers;@b@  }@b@@b@  public void setInitialCapacity(int initialCapacity)@b@  {@b@    this.initialCapacity = initialCapacity;@b@  }@b@@b@  public void setRamMegaBytes(int ramMegaBytes)@b@  {@b@    this.ramMegaBytes = ramMegaBytes;@b@  }@b@@b@  public void setConcurrencyLevel(int concurrencyLevel)@b@  {@b@    this.concurrencyLevel = concurrencyLevel;@b@  }@b@@b@  public void setDisposalTime(long disposalTime)@b@  {@b@    this.disposalTime = disposalTime;@b@  }@b@}

4.差异化配置SimplePropertiesConfiguration、YamlConfiguration子实现类

package org.apache.directmemory.conf;@b@@b@import org.yaml.snakeyaml.Yaml;@b@import org.yaml.snakeyaml.constructor.Constructor;@b@@b@public class YamlConfiguration extends DefaultConfiguration@b@{@b@  public static ConfigurationService load()@b@  {@b@    Yaml yaml = new Yaml(new Constructor(YamlConfiguration.class));@b@    return ((YamlConfiguration)yaml.load(Configuration.class.getClassLoader().getResourceAsStream("directmemory.yaml")));@b@  }@b@}

package org.apache.directmemory.conf;@b@@b@import java.util.Properties;@b@import org.slf4j.Logger;@b@import org.slf4j.LoggerFactory;@b@@b@public class SimplePropertiesConfiguration extends DefaultConfiguration@b@  implements ConfigurationService@b@{@b@  private static final Logger logger = LoggerFactory.getLogger(SimplePropertiesConfiguration.class);@b@@b@  public SimplePropertiesConfiguration()@b@  {@b@    Properties properties = new Properties();@b@    try@b@    {@b@      properties.load(getClass().getClassLoader().getResourceAsStream("directmemory.properties"));@b@      setNumberOfBuffers(new Integer(properties.getProperty("numberOfBuffers")).intValue());@b@      setInitialCapacity(new Integer(properties.getProperty("initialCapacity")).intValue());@b@      setRamMegaBytes(new Integer(properties.getProperty("ramMegaBytes")).intValue());@b@      setConcurrencyLevel(new Integer(properties.getProperty("concurrencyLevel")).intValue());@b@      setDisposalTime(new Long(properties.getProperty("disposalTime")).longValue());@b@    }@b@    catch (Exception e)@b@    {@b@      logger.warn("no properties file found or invalid file - using defaults");@b@    }@b@  }@b@}