由 Maven 构建

如何在我的应用程序中使用 Maven SCM？

创建 SCM 管理器

与丛 IOC

使用Plexus，使用 Maven SCM 非常容易，因为它在字段中注入所有依赖项，因此您只需编写最少的代码。

import org.apache.maven.scm.manager.ScmManager;

public class MyApp
{
    private ScmManager scmManager;

    public MyApp()
    {
        plexus = new Embedder();

        plexus.start();

        scmManager = (ScmManager) plexus.lookup( ScmManager.ROLE );
    }

    public ScmManager getScmManager()
    {
        return scmManager;
    }

没有 Plexus IOC

如果没有 Plexus，您必须在管理器中添加所有 SCM 提供程序，这将需要更多工作。您可以使用基本的 SCM 管理器或编写自己的：

import org.apache.maven.scm.manager.BasicScmManager;

public class MyApp
{
    private ScmManager scmManager;

    public MyApp()
    {
        scmManager = new BasicScmManager();

        //Add all SCM providers we want to use
        scmManager.setScmProvider( "git", new GitExeScmProvider() );
        scmManager.setScmProvider( "svn", new SvnExeScmProvider() );
        ...
    }

    public ScmManager getScmManager()
    {
        return scmManager;
    }

运行 SCM 命令

在调用命令之前，SCM 管理器需要一个ScmRepository。此对象包含有关 SCM 连接的所有信息。

    public ScmRepository getScmRepository( String scmUrl )
        throw Exception
    {
        ScmRepository repository;

        try
        {
            return getScmManager().makeScmRepository( scmUrl );
        }
        catch ( NoSuchScmProviderException ex )
        {
            throw new Exception( "Could not find a provider.", ex );
        }
        catch ( ScmRepositoryException ex )
        {
            throw new Exception( "Error while connecting to the repository", ex );
        }
    }

结帐命令

    public void checkOut( ScmRepository scmRepository, File workingDirectory )
        throws ScmException
    {
        if ( workingDirectory.exists() )
        {
            System.err.println( "The working directory already exist: '" + workingDirectory.getAbsolutePath() + "'." );

            return;
        }

        if ( !workingDirectory.mkdirs() )
        {
            System.err.println(
                "Error while making the working directory: '" + workingDirectory.getAbsolutePath() + "'." );

            return;
        }

        CheckOutScmResult result = scmManager.checkOut( scmRepository, new ScmFileSet( workingDirectory ) );

        checkResult( result );

        List checkedOutFiles = result.getCheckedOutFiles();

        System.out.println( "Checked out these files: " );

        for ( Iterator it = checkedOutFiles.iterator(); it.hasNext(); )
        {
            ScmFile file = (ScmFile) it.next();

            System.out.println( " " + file.getPath() );
        }
    }

更新命令

    public void update( ScmRepository scmRepository, File workingDirectory )
        throws ScmException
    {
        if ( !workingDirectory.exists() )
        {
            System.err.println( "The working directory doesn't exist: '" + workingDirectory.getAbsolutePath() + "'." );

            return;
        }

        UpdateScmResult result = scmManager.update( scmRepository, new ScmFileSet( workingDirectory ) );

        checkResult( result );

        List updatedFiles = result.getUpdatedFiles();

        System.out.println( "Updated these files: " );

        for ( Iterator it = updatedFiles.iterator(); it.hasNext(); )
        {
            ScmFile file = (ScmFile) it.next();

            System.out.println( " " + file.getPath() );
        }
    }

checkResult 方法

在每个示例命令代码中，我们使用checkResult方法，它不是必需的，但如果命令执行失败，它会很有用。

    public void checkResult( ScmResult result )
        throws Exception
    {
        if ( !result.isSuccess() )
        {
            System.err.println( "Provider message:" );

            System.err.println( result.getProviderMessage() == null ? "" : result.getProviderMessage() );

            System.err.println( "Command output:" );

            System.err.println( result.getCommandOutput() == null ? "" : result.getCommandOutput() );

            throw new Exception(
                "Command failed." + StringUtils.defaultString( result.getProviderMessage() ) );
        }
    }

示例代码

上面的代码可在此处获得：Maven SCM 客户端。