dubbo源碼編譯

源自：http://www.jianshu.com/p/0dde591f21d0

首先從https://github.com/alibaba/dubbo/archive/master.zip下載最新源碼，目前最新版本爲2.5.4-SNAPSHOT。 解壓文件。

    cd dubbo  
    mvn clean install -Dmaven.test.skip

報錯：

Non-resolvable parent POM: Could not transfer artifact com.alibaba:opensesame:pom:2.0 from/to opensesame.releases (http://code.alibabatech.com/mvn/releases)

README上已經說明了需要本地安裝“由於開源站點因爲安全問題被下掉，如果編譯時出現找不到opensesame依賴情況的，請先手動下載https://github.com/alibaba/opensesame”，那就自己安裝吧

下載opensesame，之後進入opensesame目錄，執行：mvn install 等待success吧
再次執行：

mvn clean install -Dmaven.test.skip

又是一堆的錯誤啊：

[ERROR] Failed to execute goal on project dubbo-common: Could not resolve dependencies for project com.alibaba:dubbo-common:jar:2.5.4-SNAPSHOT: Failed to collect dependencies for [org.slf4j:slf4j-api:jar:1.6.2 (provided), commons-logging:commons-logging-api:jar:1.1 (provided), log4j:log4j:jar:1.2.16 (compile), org.javassist:javassist:jar:3.15.0-GA (compile), com.alibaba:hessian-lite:jar:3.2.1-fixed-2 (compile), com.alibaba:fastjson:jar:1.1.8 (provided), org.jvnet.sorcerer:sorcerer-javac:jar:0.8 (provided), cglib:cglib-nodep:jar:2.2 (test), junit:junit:jar:4.10 (test), org.easymock:easymock:jar:3.0 (test), org.easymock:easymockclassextension:jar:3.0 (test), com.googlecode.jmockit:jmockit:jar:0.999.8 (test)]: Failed to read artifact descriptor for com.alibaba:hessian-lite:jar:3.2.1-fixed-2: Could not transfer artifact com.alibaba:hessian-lite:pom:3.2.1-fixed-2 from/to opensesame.releases (http://code.alibabatech.com/mvn/releases): Connection to http://code.alibabatech.com refused: Connection refused -> [Help 1]

很多文件從阿里的倉庫中都找不到了，到處找解決方法啊。在這個貼子上有提到了更改配置倉庫：https://github.com/alibaba/dubbo/issues/22

    <mirror>
    <id>kafeitu</id>
    <mirrorOf>central</mirrorOf>
    <name>Human Readable Name for this Mirror.</name>
    <url>http://maven.kafeitu.me/nexus/content/repositories/public</url>
    </mirror>
    <mirror>
    <id>ibiblio.org</id>
    <name>ibiblio Mirror of http://repo1.maven.org/maven2/</name>
    <url>http://mirrors.ibiblio.org/pub/mirrors/maven2</url>
    <mirrorOf>*</mirrorOf>
    </mirror>
    <mirror>
    <id>lvu.cn</id>
    <name>lvu.cn</name>
    <url>http://lvu.cn/nexus/content/groups/public</url>
    <mirrorOf>*</mirrorOf>
    </mirror>

將上面的配置加入maven配置文件setting.xml中

再次執行：

mvn clean install -Dmaven.test.skip

依然報錯：

[ERROR] Failed to execute goal on project dubbo-common: Could not resolve dependencies for project com.alibaba:dubbo-common:jar:2.5.4-SNAPSHOT: Failed to collect dependencies for [org.slf4j:slf4j-api:jar:1.6.2 (provided), commons-logging:commons-logging-api:jar:1.1 (provided), log4j:log4j:jar:1.2.16 (compile), org.javassist:javassist:jar:3.15.0-GA (compile), com.alibaba:hessian-lite:jar:3.2.1-fixed-2 (compile), com.alibaba:fastjson:jar:1.1.8 (provided), org.jvnet.sorcerer:sorcerer-javac:jar:0.8 (provided), cglib:cglib-nodep:jar:2.2 (test), junit:junit:jar:4.10 (test), org.easymock:easymock:jar:3.0 (test), org.easymock:easymockclassextension:jar:3.0 (test), com.googlecode.jmockit:jmockit:jar:0.999.8 (test)]: Failed to read artifact descriptor for com.alibaba:hessian-lite:jar:3.2.1-fixed-2: Could not find artifact com.alibaba:opensesame:pom:1.0 in ibiblio.org (http://mirrors.ibiblio.org/pub/mirrors/maven2) -> [Help 1]

在這個錯誤文件中發現了Could not find artifact com.alibaba:opensesame:pom:1.0，不是2.0麼，怎麼1.0也要。既然需要，那咱就給唄。
還記得上面自己下載的opensesame源碼不，修改下面的pom.xml，將 <version>2.0</version>中2.0修改爲1.0
執行 mvn install 等待success吧

再次執行:

mvn clean install -Dmaven.test.skip

依然出錯

[ERROR] Failed to execute goal on project dubbo-common: Could not resolve dependencies for project com.alibaba:dubbo-common:jar:2.5.4-SNAPSHOT: Could not find artifact com.alibaba:fastjson:jar:1.1.8 in ibiblio.org (http://mirrors.ibiblio.org/pub/mirrors/maven2) -> [Help 1]

不過看到那麼多的錯誤一下便少了，心理還是暗爽的，哈哈。
到http://maven.kafeitu.me/nexus/content/repositories/public/這個上面看了下fastjson可用版本有1.1.39，於是修改pom.xml,找到<fastjson_version>1.1.8</fastjson_version>，將1.1.8修改爲1.1.39

再次執行：

mvn clean install -Dmaven.test.skip

我靠還是有錯，這次居然是

    java.lang.OutOfMemoryError: PermGen space

就是不讓人省心啊，繼續解決，採用粗暴直接的方式，直接修改maven安裝目錄下bin/mvn，在上面加上這個

 MAVEN_OPTS="$MAVEN_OPTS -Xms256m -Xmx1024m -XX:MaxPermSize=128m -XX:ReservedCodeCacheSize=64m"

具體大小，可根據自己的情況調整
再次執行：

mvn clean install -Dmaven.test.skip

還是出錯了呀呀呀...

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:compile (default-compile) on project dubbo-rpc-redis: Compilation failure: Compilation failure:
[ERROR] /home/pengkw/opensource/dubbo-dubbo-2.4.10/dubbo-rpc/dubbo-rpc-redis/src/main/java/com/alibaba/dubbo/rpc/protocol/redis/RedisProtocol.java:[25,35] package org.apache.commons.pool.impl does not exist
[ERROR] /home/pengkw/opensource/dubbo-dubbo-2.4.10/dubbo-rpc/dubbo-rpc-redis/src/main/java/com/alibaba/dubbo/rpc/protocol/redis/RedisProtocol.java:[71,29] package GenericObjectPool does not exist
[ERROR] /home/pengkw/opensource/dubbo-dubbo-2.4.10/dubbo-rpc/dubbo-rpc-redis/src/main/java/com/alibaba/dubbo/rpc/protocol/redis/RedisProtocol.java:[71,67] package GenericObjectPool does not exist
[ERROR] /home/pengkw/opensource/dubbo-dubbo-2.4.10/dubbo-rpc/dubbo-rpc-redis/src/main/java/com/alibaba/dubbo/rpc/protocol/redis/RedisProtocol.java:[89,40] cannot access org.apache.commons.pool.PoolableObjectFactory
[ERROR] class file for org.apache.commons.pool.PoolableObjectFactory not found
[ERROR] final JedisPool jedisPool = new JedisPool(config, url.getHost(), url.getPort(DEFAULT_PORT),
[ERROR] -> [Help 1]

直接上解決方法：分別修改dubbo-rpc/dubbo-rpc-redis/pom.xml和dubbo-registry/dubbo-registry-redis/pom.xml文件，在dependencies下加入jar包依賴

<dependency>
    <groupId>commons-pool</groupId>
    <artifactId>commons-pool</artifactId>
    <version>1.6</version>
</dependency>

再次執行：
mvn clean install -Dmaven.test.skip
經過一段漫長的過程，終於看到了build success

好吧，至此整個源碼的編譯過程已經完成，本身沒有什麼難度，只是因爲缺少相關的jar和環境配置，導致一系列的問題。