转载请注明出处哈:http://carlosfu.iteye.com/blog/2237511

更多BigMemory Go可参考官方文档：

一、BigMemory证书：

(1). 由于BigMemory是商业版，需要从官网上注册、下载证书（目前只支持90天）和对应版本的jar包：

下载地址：http://terracotta.org/downloads/bigmemorygo，完成表单填写，完成下载。

(2). 可以将证书放到classpath下，或者加入启动参数：

(3). 证书示例： 

其中:

二、依赖

1. BigMemory依赖

<bigmemory.version>4.0.5</bigmemory.version>
<ehcache-ee.version>2.7.5</ehcache-ee.version>
<dependency>
    <groupId>org.terracotta.bigmemory</groupId>
    <artifactId>bigmemory</artifactId>
    <version>${bigmemory.version}</version>
</dependency>
<dependency>
    <groupId>net.sf.ehcache</groupId>
    <artifactId>ehcache-ee</artifactId>
    <version>${ehcache-ee.version}</version>
</dependency>

2. 序列化工具protostuff依赖

<protostuff.version>1.0.8</protostuff.version>
<dependency>
    <groupId>com.dyuproject.protostuff</groupId>
    <artifactId>protostuff-runtime</artifactId>
    <version>${protostuff.version}</version>
</dependency>
<dependency>
    <groupId>com.dyuproject.protostuff</groupId>
    <artifactId>protostuff-core</artifactId>
    <version>${protostuff.version}</version>
</dependency>

3. logback依赖（logback实现了slf4j-api）

<logback.version>1.0.13</logback.version>
<dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-core</artifactId>
    <version>${logback.version}</version>
</dependency>
<dependency>
    <groupId>ch.qos.logback</groupId>
    <artifactId>logback-classic</artifactId>
    <version>${logback.version}</version>
</dependency>    

4. 引入junit

<junit.version>4.11</junit.version>
<dependency>
   <groupId>junit</groupId>
   <artifactId>junit</artifactId>
   <version>${junit.version}</version>
</dependency>

5.最终pom配置

<properties>
    <bigmemory.version>4.0.5</bigmemory.version>
    <ehcache-ee.version>2.7.5</ehcache-ee.version>
    <protostuff.version>1.0.8</protostuff.version>
    <logback.version>1.0.13</logback.version>
    <junit.version>4.11</junit.version>
</properties>
<dependencies>
    <dependency>
        <groupId>org.terracotta.bigmemory</groupId>
        <artifactId>bigmemory</artifactId>
        <version>${bigmemory.version}</version>
    </dependency>
    <dependency>
        <groupId>net.sf.ehcache</groupId>
        <artifactId>ehcache-ee</artifactId>
        <version>${ehcache-ee.version}</version>
    </dependency>
    <dependency>
        <groupId>com.dyuproject.protostuff</groupId>
        <artifactId>protostuff-runtime</artifactId>
        <version>${protostuff.version}</version>
    </dependency>
    <dependency>
        <groupId>com.dyuproject.protostuff</groupId>
        <artifactId>protostuff-core</artifactId>
        <version>${protostuff.version}</version>
    </dependency>
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-core</artifactId>
        <version>${logback.version}</version>
    </dependency>
    <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>${logback.version}</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>${junit.version}</version>
    </dependency>
</dependencies>
<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>1.7</source>
                <target>1.7</target>
                <encoding>UTF-8</encoding>
            </configuration>
        </plugin>
    </plugins>
</build>

三、BigMemory配置 

BigMemory的配置一般也叫ehcache.xml， 放到classpath下：我们使用极简配置

<?xml version="1.0" encoding="UTF-8" ?>
<ehcache xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:noNamespaceSchemaLocation="http://ehcache.org/ehcache.xsd">    
    <cache name="firstOffHeapCache" maxBytesLocalHeap="32M" maxBytesLocalOffHeap="1024M"/>
</ehcache>

Bigmemory的配置相对于Ehcache添加了两个属性：

四、logback配置

<?xml version="1.0" encoding="UTF-8"?>
<configuration scan="true" scanPeriod="5 seconds">
    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
        </encoder>
    </appender>
    <root level="INFO">
        <appender-ref ref="STDOUT"/>
    </root>
</configuration>

 五、BigMemory测试：

1. 一个实体类：

package com.sohu.tv.bigmemory.first;
import java.util.Date;
/**
 * 俱乐部
 * 
 * @author leifu
 * @Date 2015年7月28日
 * @Time 下午1:43:53
 */
public class Club {
    /**
     * 俱乐部id
     */
    private int id;
    /**
     * 俱乐部名
     */
    private String clubName;
    /**
     * 俱乐部描述
     */
    private String clubInfo;
    /**
     * 创建日期
     */
    private Date createDate;
    /**
     * 排名
     */
    private int rank;
    public Club(int id, String clubName, String clubInfo, Date createDate, int rank) {
        super();
        this.id = id;
        this.clubName = clubName;
        this.clubInfo = clubInfo;
        this.createDate = createDate;
        this.rank = rank;
    }
    public Club() {
        super();
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getClubName() {
        return clubName;
    }
    public void setClubName(String clubName) {
        this.clubName = clubName;
    }
    public String getClubInfo() {
        return clubInfo;
    }
    public void setClubInfo(String clubInfo) {
        this.clubInfo = clubInfo;
    }
    public Date getCreateDate() {
        return createDate;
    }
    public void setCreateDate(Date createDate) {
        this.createDate = createDate;
    }
    public int getRank() {
        return rank;
    }
    public void setRank(int rank) {
        this.rank = rank;
    }
    @Override
    public String toString() {
        return "Club [id=" + id + ", clubName=" + clubName + ", clubInfo=" + clubInfo + ", createDate=" + createDate
                + ", rank=" + rank + "]";
    }
}

2. BigMemory测试（Ehcache单元测试作为测试）

(1) 单元测试：

package com.sohu.tv.bigmemory.first;
import java.util.Date;
import org.junit.BeforeClass;
import org.junit.Test;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;
/**
 * 第一个BigMemory测试
 * 
 * @author leifu
 * @Date 2015年8月12日
 * @Time 上午10:14:13
 */
public class FirstBigmemoryTest {
    private static Logger logger = LoggerFactory.getLogger(FirstBigmemoryTest.class);
    private static Cache cache;
    private static final String BIGMEORY_CACHE_NAME = "firstOffHeapCache";
     
    @BeforeClass
    public static void setUp() {
        CacheManager cacheManager = CacheManager.create(FirstBigmemoryTest.class.getClassLoader()
                .getResourceAsStream("ehcache.xml"));
        // 打印cacheManager管理的cache
        String[] cacheNameArr = cacheManager.getCacheNames();
        for (String cacheName : cacheNameArr) {
            logger.info("cacheName: {}", cacheName);
        }
        cache = cacheManager.getCache(BIGMEORY_CACHE_NAME);
    }
    @Test
    public void testCRUD() {
        logger.info("At start, bigmemory object size: {}", cache.getSize());
        // 唯一key
        String key = "football:club:1";
        Club club = new Club(1, "AC", "AC米兰", new Date(), 1);
        // 增
        Element element = new Element(key, club);
        cache.put(element);
        logger.info("after add bigmemory object size: {}", cache.getSize());
        // 查
        Element elementResult = cache.get(key);
        Club clubResult = (Club) elementResult.getObjectValue();
        logger.info("get key {} value is {}", key, clubResult.toString());
        // 修改
        club.setRank(8888);
        cache.put(element);
        logger.info("after set bigmemory object size: {}", cache.getSize());
        // 再查
        Element elementResultAgain = cache.get(key);
        Club clubResultAgain = (Club) elementResultAgain.getObjectValue();
        logger.info("get key {} again value is {}", key, clubResultAgain.toString());
        // 删
        boolean removeResult = cache.remove(key);
        logger.info("remove result is {}, after remove bigmemory object size: {}", removeResult, cache.getSize());
        // 增加一条，观察下次启动
        cache.put(element);
        logger.info("At final, bigmemory object size: " + cache.getSize());
        // 生产环境不要使用，影响性能
        logger.info("At final, bigmemory memory size: " + cache.calculateInMemorySize());
    }
}

(2) 输出报错：Club必须序列化

(3) 修复：Club实现序列化接口

public class Club implements Serializable

(4) 输出结果正常：

输出信息包含证书的验证、BigMemory堆外内存的分配

3. BigMemory测试结论：

(1) 堆外内存存储的数据需要序列化。

(2) BigMemory使用Ehcache ee可以自动完成序列化，如果使用BigMemory存储java对象，就会存在SizeOf问题（简单对象除外），所以可以使用预序列化方式序列化要存的数据。

      具体参考：BigMemory关于sizeOf引擎的测试.

(3) BigMemory启动时候，会寻找BigMemory证书。

(4) 以下是bigMemory启动时打印的DirectMemory分区概述，

根据日志,可以猜测出BigMemory预先将数据空间划分为一系列Chunk,目的为了防止内存碎片化,与Memcache内存分配策略很像.

六、BigMemory堆外内存，JVM启动参数：

-XX:MaxDirectMemorySize=4G

七、BigMemory更多使用示例：

http://www.terracotta.org/documentation/4.0/bigmemorygo/code-samples

 八、使用ProtoStuff序列化：

1. ProtoStuff序列化工具：

package com.sohu.tv.serializer;
import com.dyuproject.protostuff.LinkedBuffer;
import com.dyuproject.protostuff.ProtostuffIOUtil;
import com.dyuproject.protostuff.Schema;
import com.dyuproject.protostuff.runtime.RuntimeSchema;
import java.util.concurrent.ConcurrentHashMap;
/**
 * protostuff序列化工具
 * 
 * @author leifu
 * @Date 2015-8-22
 * @Time 上午10:05:20
 */
public class ProtostuffSerializer {
    private static ConcurrentHashMap<Class<?>, Schema<?>> cachedSchema = new ConcurrentHashMap<Class<?>, Schema<?>>();
    public <T> byte[] serialize(final T source) {
        VO<T> vo = new VO<T>(source);
        final LinkedBuffer buffer = LinkedBuffer.allocate(LinkedBuffer.DEFAULT_BUFFER_SIZE);
        try {
            final Schema<VO> schema = getSchema(VO.class);
            return serializeInternal(vo, schema, buffer);
        } catch (final Exception e) {
            throw new IllegalStateException(e.getMessage(), e);
        } finally {
            buffer.clear();
        }
    }
    public <T> T deserialize(final byte[] bytes) {
        try {
            Schema<VO> schema = getSchema(VO.class);
            VO vo = deserializeInternal(bytes, schema.newMessage(), schema);
            if (vo != null && vo.getValue() != null) {
                return (T) vo.getValue();
            }
        } catch (final Exception e) {
            throw new IllegalStateException(e.getMessage(), e);
        }
        return null;
    }
    private <T> byte[] serializeInternal(final T source, final Schema<T> schema, final LinkedBuffer buffer) {
        return ProtostuffIOUtil.toByteArray(source, schema, buffer);
    }
    private <T> T deserializeInternal(final byte[] bytes, final T result, final Schema<T> schema) {
        ProtostuffIOUtil.mergeFrom(bytes, result, schema);
        return result;
    }
    private static <T> Schema<T> getSchema(Class<T> clazz) {
        @SuppressWarnings("unchecked")
        Schema<T> schema = (Schema<T>) cachedSchema.get(clazz);
        if (schema == null) {
            schema = RuntimeSchema.createFrom(clazz);
            cachedSchema.put(clazz, schema);
        }
        return schema;
    }
}

package com.sohu.tv.serializer;
import java.io.Serializable;
/**
 * @author leifu
 * @Date 2015-8-22
 * @Time 上午10:05:44
 * @param <T>
 */
public class VO<T> implements Serializable {
    private T value;
    public VO(T value) {
        this.value = value;
    }
    public VO() {
    }
    public T getValue() {
        return value;
    }
    @Override
    public String toString() {
        return "VO{" +
                "value=" + value +
                '}';
    }
}

2. ProtoStuff + BigMemory单元测试：

@Test
public void testBigMemoryWithSerializable() {
    ProtostuffSerializer protostuffSerializer = new ProtostuffSerializer();
    // 唯一key
    String key = "football:club:1";
    byte[] clubBytes = protostuffSerializer.serialize(new Club(1, "AC", "AC米兰", new Date(), 1));
    // 增
    Element element = new Element(key, clubBytes);
    cache.put(element);
    // 查
    Element elementResult = cache.get(key);
    byte[] clubBytesResult = (byte[]) elementResult.getObjectValue();
    Club clubResult = protostuffSerializer.deserialize(clubBytesResult);
    logger.info("get key {} value is {}", key, clubResult.toString());
}

输出：