java - 如果我从 Sun JDK 切换到 OpenJDK，我必须为哪些惊喜做好准备？

Question

如果我从 Sun JDK 切换到 OpenJDK，我需要为哪些惊喜做好准备？

什么经常出错？这有多困难？

当然，每个应用程序都可能有自己的问题，但我正在寻找问题的类，这是许多人在切换 JDK 时已经遇到的问题。

Answer 1

OpenJDK 不太可能出现任何问题。它现在被认为是 100% 兼容的。但我认为最好知道哪些部分必须重写，因此不使用与 SunJDK 相同的代码。

Wikipedia entry对此有一个很好的概述:

As of May 2008, the only part of the Class library that remains proprietary and closed-source (4% as of May 2007 for OpenJDK 7, and less than 1% as of May 2008 and OpenJDK 6) is the SNMP implementation.

Since the first May 2007 release, Sun Microsystems, with the help of the community, has released as free and open-source software or replaced with free and open-source alternatives almost all the encumbered code:

• All the audio engine code, including the software synthesizer, has been released as Open-source. The closed-source software synthesizer has been replaced by a new synthesizer developed specifically for OpenJDK called Gervill,

• All cryptography classes used in the Class library have been released as Open-source,

• The code that scales and rasterizes fonts has been replaced by FreeType

• The native color management system has been replaced by LittleCMS. There is a pluggable layer in the JDK, so that the commercial version can use the old color management system and OpenJDK can use LittleCMS.

• The anti-aliasing graphics rasterizer code has been replaced by the Open-sourced Pisces renderer used in the phoneME project. This code is fully functional, but still needs some performance enhancements,

• The JavaScript plugin has been open-sourced (the Rhino JavaScript engine itself was open-sourced from the beginning).