【Plugin Develop】 How to reset the order of build step from code level?

[icetree521]

Does anybody has experience on how to reset the order of newly added build step ? I found there is an getBuildersList().set method  but it is not working.

Here is my code. Any advice is appreciated. 

FreeStyleProject p = (FreeStyleProject) build.getProject();
ORIGIN_BUILDER = (CommandInterpreter) builder;
NEW_BUILDER = new Shell("echo hello");
p.getBuildersList().remove(ORIGIN_BUILDER);
p.getBuildersList().add(NEW_BUILDER);

p.getBuildersList().set(0, NEW_BUILDER);    // Not working.

p.save();