如果在JGit中不存在,如何打开创建它的存储库？

Question

想出了:

/**
 * Create a repo at the specified directory or open one if it already
 * exists. Return a {@link Git} object...
 *
 * @param p
 *            Path to the repo root (the dir that contains the .git folder)
 * @return a "Git" object to run porcelain commands on...
 * @throws GitterException
 *             if the specified path cannot be resolved to a directory, or
 *             the repository failed to be build (...) or created
 */
public static Git open(Path p) throws GitterException {
    if (!Files.isDirectory(p)) // default LinkOption is follow links
        throw new GitterException(p + " can't be resolved to a directory");
    Repository localRepo = null;
    try {
        localRepo = new FileRepository(Paths.get(p.toString(), ".git")
            .toFile()); // do I have to specify the .git folder ?
    } catch (IOException e) {
        throw new GitterException("Failed to build Repository instance", e);
    }
    try {
        localRepo.create();
    } catch (IllegalStateException e) {
        // ISE when the repo exists !
    } catch (IOException e) {
        throw new GitterException("Failed to create Repository instance", e);
    }
    return new Git(localRepo);
}

我错过了一些明显的东西吗 这样复杂吗？

跨setMustExist(布尔)在运行BaseRepositoryBuilder可以应用它呢？

Answer 1

我能找到的最短解决方案是始终调用create()并忽略已存在的异常.

static Git openOrCreate( File gitDirectory ) throws IOException {
  Repository repository = new FileRepository( gitDirectory );
  try {
    repository.create();
  } catch( IllegalStateException repositoryExists ) {
  }
  return new Git( repository );
}

该代码有其警告.这IllegalStateException似乎是一个可能会改变并破坏上述代码的实现细节.此外,它FileRepository驻留在内部包中,不属于公共JGit API.

以下是避免这些问题的解决方案:

static Git openOrCreate( File gitDirectory ) throws IOException, GitAPIException {
  Git git;
  FileRepositoryBuilder repositoryBuilder = new FileRepositoryBuilder();
  repositoryBuilder.addCeilingDirectory( gitDirectory );
  repositoryBuilder.findGitDir( gitDirectory );
  if( repositoryBuilder.getGitDir() == null ) {
    git = Git.init().setDirectory( gitDirectory.getParentFile() ).call();
  } else {
    git = new Git( repositoryBuilder.build() );
  }
  return git;
}

请注意,省略了异常处理,以便专注于片段的实际用途.

setMustExist无法按需创建存储库.如果在指定位置找不到存储库,则只会导致build()提升RepositoryNotFoundException.

Repository表示存储库本身,而Git充当工厂来创建在其包装的存储库上运行的命令.旁边的工厂方法有close(),它只是委托给Repository.close().

存储库维护一个递减的使用计数器close().您可以在关闭后通过Git或Repository自己的方法继续使用存储库,但如有必要,它将重新打开.为避免泄漏文件句柄,您不应在关闭后使用存储库.

可以找到有关如何使用JGit访问和初始化存储库的深入讨论

这里:http://www.codeaffine.com/2014/09/22/access-git-repository-with-jgit/和

这里:http://www.codeaffine.com/2015/05/06/jgit-initialize-repository/