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杨周 极狐GitLab 高级解决方案架构师
代码越写越标准是优良开发者的成长之路，但很多人对老我的项目感到有心无力，因为太不标准了，所有人停下来一起修复也要花费很长时间，而且一次改变太多难以确保可靠性，怎么办？
有的语言能够借助 Git diff 把本次批改的代码挑出来，实现增量扫描，但 Java 很难这么做。
有的人在继续集成里配置了标准扫描工具，但报错之后须要在成千上万行 log 里查找，升高了研发效率。
Checkstyle 是业界出名的开源扫描工具，可扫描 Sun、Google 等代码标准，提供Maven、Gradle 插件。本文以 Java 我的项目配置 Checkstyle 扫描工具为例，分享毁灭这些问题的方法：
1. 将代码标准问题显示在「合并申请页面」，大幅度提高研发效率；
2. 增量代码标准报告。
下文别离介绍「Java Maven 我的项目」和「Java Gradle 我的项目」的配置办法。
通过极狐GitLab CI 平滑落地 Java 增量代码标准Checkstyle Maven
在我的项目中引入 Checkstyle 插件，并下载代码标准：
$ vi pom.xml<plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-checkstyle-plugin</artifactId> <version>3.2.0</version> <configuration> <encoding>UTF-8</encoding> <consoleOutput>true</consoleOutput> <failsOnError>true</failsOnError> <violationSeverity>warning</violationSeverity> <configLocation>config/checkstyle/checkstyle.xml</configLocation> </configuration> </plugin>$ mkdir -p config/checkstyle/$ wget https://raw.githubusercontent.com/checkstyle/checkstyle/checkstyle-9.3/src/main/resources/google_checks.xml -O config/checkstyle/checkstyle.xml执行全量扫描命令，查看成果：
$ ./mvnw checkstyle:check[WARN] Demo.java:6:1: 短少 Javadoc 。 [MissingJavadocType][WARN] Demo.java:9:1: 行内含有制表符 tab 。 [FileTabCharacter][WARN] Demo.java:9:9: 'method def modifier' 缩进了8个缩进符，应为2个。 [Indentation]在极狐GitLab 继续集成中执行强制扫描：
$ vi .gitlab-ci.ymlcheckstyle: script: - ./mvnw checkstyle:check当扫描工具报错，继续集成退出，想看代码标准问题，须要到 log 中查找。很多继续集成产品只做到了这一步，但这升高了开发效率，因而极狐GitLab 更进一步——采集「代码品质报告」。
在我的项目中引入 violations-maven-plugin，它会将 Checkstyle 报告转换成极狐GitLab 规范格局。
$ vi pom.xml<plugin> <groupId>se.bjurr.violations</groupId> <artifactId>violations-maven-plugin</artifactId> <version>1.50.4</version> <executions> <execution> <phase>validate</phase> <goals> <goal>violations</goal> </goals> <configuration> <!-- Optional config --> <!-- 0 is disabled --> <maxReporterColumnWidth>0</maxReporterColumnWidth> <maxRuleColumnWidth>0</maxRuleColumnWidth> <maxSeverityColumnWidth>0</maxSeverityColumnWidth> <maxLineColumnWidth>0</maxLineColumnWidth> <maxMessageColumnWidth>30</maxMessageColumnWidth> <!-- Will create a CodeClimate JSON report. --> <codeClimateFile>gl-code-quality-report.json</codeClimateFile> <!-- Global configuration, remove if you dont want to report violations for the entire repo. --> <!-- INFO, WARN or ERROR --> <minSeverity>INFO</minSeverity> <!-- PER_FILE_COMPACT, COMPACT or VERBOSE --> <detailLevel>VERBOSE</detailLevel> <!-- Will fail the build if total number of found violations is higher --> <maxViolations>99999999</maxViolations> <!-- Will print violations found in diff --> <printViolations>true</printViolations> <!-- Diff configuration, remove if you dont want to report violations for files changed between specific revisions. --> <!-- Can be empty (ignored), Git-commit or any Git-reference --> <diffFrom></diffFrom> <!-- Same as above --> <diffTo></diffTo> <!-- INFO, WARN or ERROR --> <diffMinSeverity>INFO</diffMinSeverity> <!-- PER_FILE_COMPACT, COMPACT or VERBOSE --> <diffDetailLevel>VERBOSE</diffDetailLevel> <!-- Will fail the build if number of violations, in the diff within from/to, is higher --> <diffMaxViolations>99</diffMaxViolations> <!-- Will print violations found in diff --> <diffPrintViolations>true</diffPrintViolations> <!-- Where to look for Git --> <gitRepo>.</gitRepo> <!-- This is mandatory regardless of if you want to report violations between revisions or the entire repo. --> <violations> <violation> <parser>CHECKSTYLE</parser> <reporter>Checkstyle</reporter> <folder>.</folder> <pattern>.*/target/checkstyle-result\.xml$</pattern> </violation> </violations> </configuration> </execution> </executions></plugin>在极狐GitLab CI 中采集代码标准报告：
image: eclipse-temurin:8cache: paths: - /root/.m2stages: - lint - buildcheckstyle: allow_failure: true stage: lint script: - ./mvnw checkstyle:check artifacts: when: always untracked: truereport: stage: lint script: - ./mvnw validate needs: - job: checkstyle artifacts: true artifacts: reports: codequality: gl-code-quality-report.jsoncompile: stage: build script: - ./mvnw package -Dmaven.test.skip=true artifacts: untracked: true能够看到在开发人员频繁应用的「合并申请」页面，间接显示了「代码标准问题」，供开发人员自助修复以及揭示评审的共事留神，这样能够无效进步研发效率。
老我的项目第一次配置代码标准可能会呈现很多谬误（比方上图有 7746 个），没关系，先将标准合并进入骨干，下次批改代码发动合并申请时，极狐GitLab 将展现「增量代码品质报告」，而无需任何简单设置。比方下图就只有 5 个新问题了：
通过极狐GitLab CI 平滑落地 Java 增量代码标准 Checkstyle Gradle
「Java Gradle 我的项目」和「Java Maven 我的项目」的配置办法统一：
在我的项目中引入 Checkstyle 插件，并下载代码标准：
$ vi build.gradleplugins { id 'checkstyle'}checkstyle { toolVersion = '9.3' maxWarnings = 0 maxErrors = 0}$ mkdir -p config/checkstyle/$ wget https://raw.githubusercontent.com/checkstyle/checkstyle/checkstyle-9.3/src/main/resources/google_checks.xml -O config/checkstyle/checkstyle.xml执行全量扫描命令，查看成果：
$ ./gradlew check[WARN] Demo.java:6:1: 短少 Javadoc 。 [MissingJavadocType][WARN] Demo.java:9:1: 行内含有制表符 tab 。 [FileTabCharacter][WARN] Demo.java:9:9: 'method def modifier' 缩进了8个缩进符，应为2个。 [Indentation]在极狐GitLab 继续集成中执行强制扫描：
$ vi .gitlab-ci.ymlcheckstyle: script: - ./gradlew check同样，在我的项目中引入 violations-maven-plugin，它会将 Checkstyle 报告转换成极狐 GitLab 规范格局。
$ vi build.gradlebuildscript { repositories { maven { url 'https://plugins.gradle.org/m2/' } } dependencies { classpath "se.bjurr.violations:violations-gradle-plugin:1.52.2" }}task violations(type: se.bjurr.violations.gradle.plugin.ViolationsTask) { // // Optional config // maxReporterColumnWidth = 0 // 0 means "no limit" maxRuleColumnWidth = 60 maxSeverityColumnWidth = 0 maxLineColumnWidth = 0 maxMessageColumnWidth = 50 codeClimateFile = file('gl-code-quality-report.json') // Will create a CodeClimate JSON report. violationsFile = file('violations-file.json') // Will create a normalized JSON report. // // Global configuration, remove if you dont want to report violations for // the entire repo. // minSeverity = 'INFO' // INFO, WARN or ERROR detailLevel = 'VERBOSE' // PER_FILE_COMPACT, COMPACT or VERBOSE maxViolations = 99999999 // Will fail the build if total number of found violations is higher printViolations = true // Will print violations found in diff // // Diff configuration, remove if you dont want to report violations for // files changed between specific revisions. // // diff-properties can be supplied with something like: // // ./gradlew violations -PdiffFrom=e4de20e -PdiffTo=HEAD // // And in Travis, you could add: // // script: // - 'if [ "$TRAVIS_PULL_REQUEST" != "false" ]; then bash ./gradlew check -PdiffFrom=$TRAVIS_PULL_REQUEST_BRANCH -PdiffTo=$TRAVIS_BRANCH ; fi' // diffFrom = project.properties.diffFrom // Can be empty (ignored), Git-commit or any Git-reference diffTo = project.properties.diffTo // Same as above diffMinSeverity = 'INFO' // INFO, WARN or ERROR diffDetailLevel = 'VERBOSE' // PER_FILE_COMPACT, COMPACT or VERBOSE diffMaxViolations = 99 // Will fail the build if number of violations, in the diff within from/to, is higher diffPrintViolations = true // Will print violations found in diff gitRepo = file('.') // Where to look for Git // // This is mandatory regardless of if you want to report violations between // revisions or the entire repo. // // Many more formats available, see: https://github.com/tomasbjerre/violations-lib violations = [ ["CHECKSTYLE", buildDir.path, ".*/checkstyle/.*\\.xml\$", "Checkstyle"] ]}在极狐GitLab CI 中采集代码标准报告：
image: eclipse-temurin:8cache: paths: - /root/.m2stages: - lint - buildcheckstyle: allow_failure: true stage: lint script: - ./gradlew check artifacts: when: always untracked: truereport: stage: lint script: - ./gradlew violations needs: - job: checkstyle artifacts: true artifacts: reports: codequality: gl-code-quality-report.jsoncompile: stage: build script: - ./gradlew build -x check -x test artifacts: untracked: true残余步骤与「Java Gradle 我的项目」统一：开发人员频繁应用的「合并申请」页面，间接显示了「代码标准问题」，供开发人员自助修复以及揭示评审的共事留神，无效进步研发效率。
老我的项目第一次配置代码标准可能会呈现很多谬误（比方上图有 7746 个），没关系，先将标准合并进入骨干，下次批改代码发动合并申请时，极狐GitLab 将展现「增量代码品质报告」，而无需任何简单设置，比方下图只有 5 个新问题：
这样，咱们就通过极狐GitLab 平滑落地了 Java 增量代码标准，让我的项目代码越来越优雅。