一、jgit是什么

     如果你想在一个 Java 程序中使用 Git ，有一个功能齐全的 Git 库，那就是 JGit 。 JGit 是一个用 Java 写成的功能相对健全的 Git 的实现，它在 Java 社区中被广泛使用。 JGit 项目由 Eclipse 维护。

二、引入jgit

<jgit.version>6.6.0.202305301015-r</jgit.version>

<dependency>
    <groupId>org.eclipse.jgit</groupId>
    <artifactId>org.eclipse.jgit</artifactId>
    <version>${jgit.version}</version>
</dependency>

三、操作简介

1、初始化git环境

#初始化git环境
 CredentialsProvider credential = GitUtils.createCredentialsProvider(cicdPropertiesInfo.getUserName(), cicdPropertiesInfo.getPassWord());
 Git git = GitUtils.getGit(cicdPropertiesInfo.getGitUrl(), credential, localFilePath);

2、创建新分支

 String targetBranchName = "release_" + System.currentTimeMillis();
 String test = GitUtils.createBranch(git, credential, targetBranchName);

3、checkout

GitUtils.checkout(git, credential, cicdPropertiesInfo.getBranchName());

4、分支融合

MergeResult mergeResult = GitUtils.mergeBranch(git, cicdPropertiesInfo.getBranchName(), targetBranchName);

5、代码提交

boolean jgitCommit = GitUtils.commitFiles(git, credential, "*", "jgit commit");

四、封装的工具类

import lombok.extern.slf4j.Slf4j;
import org.eclipse.jgit.api.*;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.SymbolicRef;
import org.eclipse.jgit.transport.*;
import org.eclipse.jgit.transport.RemoteRefUpdate.Status;

import java.io.File;
import java.io.IOException;
import java.util.List;
import java.util.stream.Collectors;

/**
 * Git工具类
 *
 * @author chentiefeng
 * @date 2021/2/10 14:02
 */
@Slf4j
public class GitUtils {

    /**
     * 提交文件到仓库 (包括新增的、更改的、删除的)
     *
     * @param git
     * @param credential
     * @param filePattern
     * @param commitMessage
     * @return
     * @throws GitAPIException
     * @throws IOException
     */
    public static boolean commitFiles(Git git, CredentialsProvider credential, String filePattern, String commitMessage) throws GitAPIException, IOException {
        //添加
        git.add().addFilepattern(filePattern).call();
        git.add().addFilepattern(filePattern).setUpdate(true).call();
        //提交
        git.commit().setMessage(commitMessage).call();
        //推送到远程
        Iterable<PushResult> pushResults = git.push().setCredentialsProvider(credential).call();
        printCommitPushResult(pushResults, git.getRepository().getBranch(), commitMessage);
        return true;
    }

    /**
     * 打印提交文件的日志
     *
     * @param results
     */
    private static void printCommitPushResult(Iterable<PushResult> results, String branchName, String commitMessage) {
        log.info("git add && git commit -m '{}'", commitMessage);
        log.info("git push");
        for (PushResult result : results) {
            RemoteRefUpdate remoteRefUpdate = result.getRemoteUpdate(GitBranchType.LOCAL.getPrefix() + branchName);
            if (Status.OK.equals(remoteRefUpdate.getStatus())) {
                log.info("remote: " + result.getMessages().substring(0, result.getMessages().length() - 1));
            } else {
                log.error("remote: " + result.getMessages());
            }
            log.info("To {}", result.getURI());
        }
    }

    /**
     * 删除分支
     *
     * @param git
     * @param credential
     * @param branchName
     * @return
     * @throws GitAPIException
     * @throws IOException
     */
    public static boolean removeBranch(Git git, CredentialsProvider credential, String branchName) throws GitAPIException, IOException {
        // master分支不能删除
        if ("master".equals(branchName)) {
            return false;
        }

        String oldBranch = git.getRepository().getBranch();
        //如果要删除的分支等于当前分支，切换到master
        if (oldBranch.equals(branchName)) {
            git.checkout().setName("master").call();
        }
        git.branchDelete().setBranchNames(GitBranchType.LOCAL.getPrefix() + branchName).setForce(true).call();
        git.branchDelete().setBranchNames(GitBranchType.REMOTE.getPrefix() + branchName).setForce(true).call();
        //推送到远程
        String branchFullName = GitBranchType.LOCAL.getPrefix() + branchName;
        RefSpec refSpec = new RefSpec(":" + branchFullName).setForceUpdate(true);
        Iterable<PushResult> results = git.push().setCredentialsProvider(credential).setRefSpecs(refSpec).call();
        printRemoveBranchResult(results, branchFullName, branchName);
        return true;
    }

    /**
     * 打印删除分支的日志
     *
     * @param results
     * @param branchFullName
     */
    private static void printRemoveBranchResult(Iterable<PushResult> results, String branchFullName, String branchName) {
        log.info("git push origin --delete {}", branchName);
        for (PushResult result : results) {
            RemoteRefUpdate remoteRefUpdate = result.getRemoteUpdate(branchFullName);
            if (Status.OK.equals(remoteRefUpdate.getStatus())) {
                log.info("remote: " + result.getMessages().substring(0, result.getMessages().length() - 1));
            } else {
                log.error("remote: " + result.getMessages());
            }
            log.info("To {}", result.getURI());
            log.info("- [deleted]    {}", branchName);
        }
    }

    /**
     * 创建分支
     *
     * @param git
     * @param branchName
     * @return
     * @throws GitAPIException
     * @throws IOException
     */
    public static String createBranch(Git git, CredentialsProvider credential, String branchName) throws GitAPIException, IOException {
        //如果本地存在分支,直接返回
        if (getBranches(git, GitBranchType.LOCAL).contains(branchName)) {
            return branchName;
        }
        //如果远端存在分支，则创建本地分支
        if (getBranches(git, GitBranchType.REMOTE).contains(branchName)) {
            String oldBranch = git.getRepository().getBranch();
            git.checkout().setName(branchName).setCreateBranch(true).call();
            git.checkout().setName(oldBranch).call();
            return branchName;
        }
        //新建分支
        git.branchCreate().setName(branchName).call();
        String oldBranch = git.getRepository().getBranch();
        git.checkout().setName(branchName).call();
        //推送到远程
        git.push().setCredentialsProvider(credential).call();
        git.checkout().setName(oldBranch).call();
        return branchName;
    }

    /**
     * 获取所有分支
     *
     * @param git
     * @param branchType 分支类型，分为本地分支和远程分支
     * @return
     * @throws GitAPIException
     * @throws IOException
     */
    public static List<String> getBranches(Git git, GitBranchType branchType) throws GitAPIException, IOException {
        if (GitBranchType.LOCAL.equals(branchType)) {
            List<Ref> refs = git.branchList().call();
            return refs.stream().map(ref -> ref.getName().substring(GitBranchType.LOCAL.getPrefix().length()))
                    .collect(Collectors.toList());
        } else {
            List<Ref> refs = git.getRepository().getRefDatabase().getRefs();
            return refs.stream().filter(item -> !(item instanceof SymbolicRef))
                    .filter(item -> item.getName().startsWith(GitBranchType.REMOTE.getPrefix()))
                    .map(ref -> ref.getName().substring(GitBranchType.REMOTE.getPrefix().length()))
                    .collect(Collectors.toList());
        }
    }

    /**
     * 获取git对象
     *
     * @param gitUrl              git的http路径
     * @param credentialsProvider 认证
     * @param localPath           本地路径
     * @return
     * @throws IOException
     * @throws GitAPIException
     */
    public static Git getGit(String gitUrl, CredentialsProvider credentialsProvider, String localPath) throws IOException, GitAPIException {
        if (new File(localPath).exists()) {
            return Git.open(new File(localPath));
        } else {
            return Git.cloneRepository().setCredentialsProvider(credentialsProvider).setURI(gitUrl)
                    .setDirectory(new File(localPath)).call();
        }
    }

    /**
     * 关闭git
     *
     * @param git
     */
    public static void closeGit(Git git) {
        git.close();
    }

    /**
     * 创建Git认证信息
     *
     * @param username
     * @param password
     * @return
     */
    public static CredentialsProvider createCredentialsProvider(String username, String password) {
        return new UsernamePasswordCredentialsProvider(username, password);
    }

    /**
     * 代码合并
     *
     * @param git
     * @param sourceBranchName
     * @param targetBranchName
     * @return
     * @throws Exception
     */
    public static MergeResult mergeBranch(Git git, String sourceBranchName, String targetBranchName) throws Exception {
        Ref refdev = git.checkout().setName(sourceBranchName).call(); //切换源头分支获取源头分支信息
        git.checkout().setName(targetBranchName).call();   //切换回被合并分支
        // git merge [sourceBranchName]
        MergeResult mergeResult = git.merge().include(refdev)  // 合并源头分支到目标分支
                .setCommit(true)           // 设置合并后同时提交
                .setFastForward(MergeCommand.FastForwardMode.NO_FF)// 分支合并策略，--ff代表快速合并， --no-ff代表普通合并
                .setMessage("Merge sourceBranchName into targetBranchName.")     //设置提交信息
                .call();
        return mergeResult;
    }

    /**
     * 拉代码
     *
     * @param git
     * @param credentialsProvider
     * @return
     * @throws Exception
     */
    public static PullResult pull(Git git, CredentialsProvider credentialsProvider, String branchName) throws Exception {
        PullResult call = git.pull().setCredentialsProvider(credentialsProvider).setRemoteBranchName(branchName).call();
        return call;
    }

    public static void checkout(Git git, CredentialsProvider credentialsProvider, String branchName) throws Exception {
        git.pull().setCredentialsProvider(credentialsProvider).setRemoteBranchName(branchName).call();
        boolean existBranch = false;
        //列出所有的分支名称，判断分支是否存在
        List<Ref> branchList = git.branchList().setListMode(ListBranchCommand.ListMode.ALL).call();
        for (Ref ref : branchList) {
            if (("refs/remotes/origin/" + branchName).equals(ref.getName())) {
                existBranch = true;
            }
        }
        if (!existBranch) {
            log.error("分支{}不存在，请确认", branchName);
            throw new RuntimeException(
                    "分支" + branchName + "不存在，请确认");
        }
        boolean existLocalBranch = false;
        branchList = git.branchList().call();
        for (Ref ref : branchList) {
            if (ref.getName().equals("refs/heads/" + branchName)) {
                existLocalBranch = true;
            }
        }
        if (existLocalBranch) {
            // 存在则切换本地分支
            git.checkout().setName(branchName).call();
        } else {
            // 不存在则切换为远程分支
            git.checkout().setCreateBranch(true).setName(branchName)
                    .setUpstreamMode(CreateBranchCommand.SetupUpstreamMode.TRACK)
                    .setStartPoint("origin/" + branchName).call();
        }


    }
}