1、下载 jacoco

官网地址：EclEmma - JaCoCo Java Code Coverage Library

2、拷贝 jar 包

下载好后，找到这两个文件，然后找到被测项目

3、启动 jacocoagent，监控被测项目

java -javaagent:jacocoagent.jar=includes=*,output=tcpserver,port=6300,address=localhost,append=true -jar jacoco-demo-1.0.0.jar 
#jacoco-demo-1.0.0.jar为被测项目jar包

$ java -javaagent:jacocoagent.jar=includes=*,output=tcpserver,port=6300,address=localhost,append=true -jar jacoco-demo-1.0.0.jar
16:23:53,451 |-INFO in ch.qos.logback.classic.LoggerContext[default] - This is logback-classic version 1.4.5
16:23:53,467 |-INFO in ch.qos.logback.classic.LoggerContext[default] - Could NOT find resource [logback-test.xml]
16:23:53,483 |-INFO in ch.qos.logback.classic.LoggerContext[default] - Found resource [logback.xml] at [jar:file:/E:/soft/jacoco/jacoco-0.8.10/lib/jacoco-demo-1.0.0.jar!/BOOT-INF/classes!/logback.xml]
16:23:53,499 |-INFO in ch.qos.logback.core.joran.spi.ConfigurationWatchList@4808bc9b - URL [jar:file:/E:/soft/jacoco/jacoco-0.8.10/lib/jacoco-demo-1.0.0.jar!/BOOT-INF/classes!/logback.xml] is not of type file
16:23:53,658 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - Processing appender named [stdout]
16:23:53,658 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - About to instantiate appender of type [ch.qos.logback.core.ConsoleAppender]
16:23:53,674 |-INFO in ch.qos.logback.core.model.processor.ImplicitModelHandler - Assuming default type [ch.qos.logback.classic.encoder.PatternLayoutEncoder] for [encoder] property
16:23:53,722 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - Processing appender named [ErrorFile]
16:23:53,722 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - About to instantiate appender of type [ch.qos.logback.core.rolling.RollingFileAppender]
16:23:53,738 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@1893960929 - No compression will be used
16:23:53,738 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@1893960929 - Will use the pattern c:/logs/error/error-%d{yyyy-MM-dd}.%i.log for the active file
16:23:53,770 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@2ca923bb - The date pattern is 'yyyy-MM-dd' from file name pattern 'c:/logs/error/error-%d{yyyy-MM-dd}.%i.log'.
16:23:53,770 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@2ca923bb - Roll-over at midnight.
16:23:53,786 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@2ca923bb - Setting initial period to Sun Aug 13 16:11:32 CST 2023
16:23:53,786 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@2ca923bb - SizeAndTimeBasedFNATP is deprecated. Use SizeAndTimeBasedRollingPolicy instead
16:23:53,786 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@2ca923bb - For more information see http://logback.qos.ch/manual/appenders.html#SizeAndTimeBasedRollingPolicy
16:23:53,794 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - This appender no longer admits a layout as a sub-component, set an encoder instead.
16:23:53,794 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - To ensure compatibility, wrapping your layout in LayoutWrappingEncoder.
16:23:53,794 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - See also http://logback.qos.ch/codes.html#layoutInsteadOfEncoder for details
16:23:53,794 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - Active log file name: c:/logs/error/error.log
16:23:53,794 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - File property is set to [c:/logs/error/error.log]
16:23:53,802 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - Processing appender named [AllFile]
16:23:53,802 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - About to instantiate appender of type [ch.qos.logback.core.rolling.RollingFileAppender]
16:23:53,802 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@333392524 - No compression will be used
16:23:53,802 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@333392524 - Will use the pattern c:/logs/all/all-%d{yyyy-MM-dd}.%i.log for the active file
16:23:53,802 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@1ebea008 - The date pattern is 'yyyy-MM-dd' from file name pattern 'c:/logs/all/all-%d{yyyy-MM-dd}.%i.log'.
16:23:53,802 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@1ebea008 - Roll-over at midnight.
16:23:53,802 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@1ebea008 - Setting initial period to Sun Aug 13 16:22:01 CST 2023
16:23:53,802 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@1ebea008 - SizeAndTimeBasedFNATP is deprecated. Use SizeAndTimeBasedRollingPolicy instead
16:23:53,802 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@1ebea008 - For more information see http://logback.qos.ch/manual/appenders.html#SizeAndTimeBasedRollingPolicy
16:23:53,802 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - This appender no longer admits a layout as a sub-component, set an encoder instead.
16:23:53,802 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - To ensure compatibility, wrapping your layout in LayoutWrappingEncoder.
16:23:53,802 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - See also http://logback.qos.ch/codes.html#layoutInsteadOfEncoder for details
16:23:53,802 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - Active log file name: c:/logs/all/all.log
16:23:53,802 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - File property is set to [c:/logs/all/all.log]
16:23:53,802 |-INFO in ch.qos.logback.classic.model.processor.RootLoggerModelHandler - Setting level of ROOT logger to INFO
16:23:53,802 |-INFO in ch.qos.logback.core.model.processor.AppenderRefModelHandler - Attaching appender named [stdout] to Logger[ROOT]
16:23:53,802 |-INFO in ch.qos.logback.core.model.processor.AppenderRefModelHandler - Attaching appender named [ErrorFile] to Logger[ROOT]
16:23:53,802 |-INFO in ch.qos.logback.core.model.processor.AppenderRefModelHandler - Attaching appender named [AllFile] to Logger[ROOT]
16:23:53,802 |-INFO in ch.qos.logback.core.model.processor.DefaultProcessor@72d6b3ba - End of configuration.
16:23:53,802 |-INFO in ch.qos.logback.classic.joran.JoranConfigurator@1787f2a0 - Registering current configuration as safe fallback point

16:23:54,405 |-INFO in ch.qos.logback.core.joran.spi.ConfigurationWatchList@64030b91 - URL [jar:file:/E:/soft/jacoco/jacoco-0.8.10/lib/jacoco-demo-1.0.0.jar!/BOOT-INF/classes!/logback.xml] is not of type file
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - Processing appender named [stdout]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - About to instantiate appender of type [ch.qos.logback.core.ConsoleAppender]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.ImplicitModelHandler - Assuming default type [ch.qos.logback.classic.encoder.PatternLayoutEncoder] for [encoder] property
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - Processing appender named [ErrorFile]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - About to instantiate appender of type [ch.qos.logback.core.rolling.RollingFileAppender]
16:23:54,422 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@540206885 - No compression will be used
16:23:54,422 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@540206885 - Will use the pattern c:/logs/error/error-%d{yyyy-MM-dd}.%i.log for the active file
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@4d23015c - The date pattern is 'yyyy-MM-dd' from file name pattern 'c:/logs/error/error-%d{yyyy-MM-dd}.%i.log'.
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@4d23015c - Roll-over at midnight.
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@4d23015c - Setting initial period to Sun Aug 13 16:11:32 CST 2023
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@4d23015c - SizeAndTimeBasedFNATP is deprecated. Use SizeAndTimeBasedRollingPolicy instead
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@4d23015c - For more information see http://logback.qos.ch/manual/appenders.html#SizeAndTimeBasedRollingPolicy
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - This appender no longer admits a layout as a sub-component, set an encoder instead.
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - To ensure compatibility, wrapping your layout in LayoutWrappingEncoder.
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - See also http://logback.qos.ch/codes.html#layoutInsteadOfEncoder for details
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - Active log file name: c:/logs/error/error.log
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[ErrorFile] - File property is set to [c:/logs/error/error.log]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - Processing appender named [AllFile]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderModelHandler - About to instantiate appender of type [ch.qos.logback.core.rolling.RollingFileAppender]
16:23:54,422 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@943659381 - No compression will be used
16:23:54,422 |-INFO in c.q.l.core.rolling.TimeBasedRollingPolicy@943659381 - Will use the pattern c:/logs/all/all-%d{yyyy-MM-dd}.%i.log for the active file
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@441cc260 - The date pattern is 'yyyy-MM-dd' from file name pattern 'c:/logs/all/all-%d{yyyy-MM-dd}.%i.log'.
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@441cc260 - Roll-over at midnight.
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@441cc260 - Setting initial period to Sun Aug 13 16:22:01 CST 2023
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@441cc260 - SizeAndTimeBasedFNATP is deprecated. Use SizeAndTimeBasedRollingPolicy instead
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP@441cc260 - For more information see http://logback.qos.ch/manual/appenders.html#SizeAndTimeBasedRollingPolicy
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - This appender no longer admits a layout as a sub-component, set an encoder instead.
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - To ensure compatibility, wrapping your layout in LayoutWrappingEncoder.
16:23:54,422 |-WARN in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - See also http://logback.qos.ch/codes.html#layoutInsteadOfEncoder for details
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - Active log file name: c:/logs/all/all.log
16:23:54,422 |-INFO in ch.qos.logback.core.rolling.RollingFileAppender[AllFile] - File property is set to [c:/logs/all/all.log]
16:23:54,422 |-INFO in ch.qos.logback.classic.model.processor.RootLoggerModelHandler - Setting level of ROOT logger to INFO
16:23:54,422 |-INFO in ch.qos.logback.classic.jul.LevelChangePropagator@73a00e09 - Propagating INFO level on Logger[ROOT] onto the JUL framework
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderRefModelHandler - Attaching appender named [stdout] to Logger[ROOT]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderRefModelHandler - Attaching appender named [ErrorFile] to Logger[ROOT]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.AppenderRefModelHandler - Attaching appender named [AllFile] to Logger[ROOT]
16:23:54,422 |-INFO in ch.qos.logback.core.model.processor.DefaultProcessor@26dcd8c0 - End of configuration.
16:23:54,422 |-INFO in org.springframework.boot.logging.logback.SpringBootJoranConfigurator@66e889df - Registering current configuration as safe fallback point


  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.0.2)

[INFO ] 2023-08-13 16:23:54.557 [main] com.ybw.JacocoDemoApplication - Starting JacocoDemoApplication using Java 17.0.4.1 with PID 11912 (E:\soft\jacoco\jacoco-0.8.10\lib\jacoco-demo-1.0.0.jar started by 魏先生 in E:\soft\jacoco\jacoco-0.8.10\lib)
[INFO ] 2023-08-13 16:23:54.557 [main] com.ybw.JacocoDemoApplication - No active profile set, falling back to 1 default profile: "default"
[INFO ] 2023-08-13 16:23:55.593 [main] o.s.b.w.e.tomcat.TomcatWebServer - Tomcat initialized with port(s): 8080 (http)
[INFO ] 2023-08-13 16:23:55.597 [main] o.a.coyote.http11.Http11NioProtocol - Initializing ProtocolHandler ["http-nio-8080"]
[INFO ] 2023-08-13 16:23:55.597 [main] o.a.catalina.core.StandardService - Starting service [Tomcat]
[INFO ] 2023-08-13 16:23:55.597 [main] o.a.catalina.core.StandardEngine - Starting Servlet engine: [Apache Tomcat/10.1.5]
[INFO ] 2023-08-13 16:23:55.673 [main] o.a.c.c.C.[Tomcat].[localhost].[/] - Initializing Spring embedded WebApplicationContext
[INFO ] 2023-08-13 16:23:55.688 [main] o.s.b.w.s.c.ServletWebServerApplicationContext - Root WebApplicationContext: initialization completed in 1042 ms
[INFO ] 2023-08-13 16:23:56.038 [main] o.a.coyote.http11.Http11NioProtocol - Starting ProtocolHandler ["http-nio-8080"]
[INFO ] 2023-08-13 16:23:56.054 [main] o.s.b.w.e.tomcat.TomcatWebServer - Tomcat started on port(s): 8080 (http) with context path ''
[INFO ] 2023-08-13 16:23:56.054 [main] com.ybw.JacocoDemoApplication - Started JacocoDemoApplication in 2.115 seconds (process running for 2.942)

参数描述

includes=*：这个代表了，启动时需要进行字节码插桩的包过滤，*代表所有的class文件加载都需要进行插桩。
- 你可以写成: includes=com.test.service.*；这个参数我们可以用来做maven多模块的覆盖率，比如我们只想查看service服务层的覆盖率，我们可以通过设置包路径的方式进行只统计当前包的覆盖率。
output=tcpserver：output主要四个参数
- file: At VM termination execution data is written to the file specified in the destfile attribute.（当jvm停止掉的时候产出dump文件，即服务挂了产出dump文件）
- tcpserver: The agent listens for incoming connections on the TCP port specified by the address and port attribute. Execution data is written to this TCP connection.（常用模式，将jacocoaget作为服务，每次通过cli包进行dump命令去获取dump包）
- tcpclient: At startup the agent connects to the TCP port specified by the address and port attribute. Execution data is written to this TCP connection.（将jacocoagent做为客户端，向指定ip和端口的服务推送dump信息）
- none: Do not produce any output.（不产出任何dump，dump个寂寞，忽略）
port=6300：这是jacoco开启的tcpserver的端口，请注意这个端口不能被占用。
address=localhost：这是对外开发的tcpserver的访问地址。
- 可以配置127.0.0.1,也可以配置为实际访问ip配置为127.0.0.1的时候，dump数据只能在这台服务器上进行dump，就不能通过远程方式dump数据。配置为实际的ip地址的时候，就可以在任意一台机器上(前提是ip要通，不通都白瞎)，通过ant xml或者api方式dump数据。
- 举个栗子：我如上配置了192.168.110.1:2014作为jacoco的tcpserver启动服务，
  那我可以在任意一台机器上进行数据的dump，比如在我本机windows上用api或者xml方式调用dump。如果我配置了127.0.0.1:2014作为启动服务器，那么我只能在这台测试机上进行dump，其他的机器都无法连接到这个tcpserver进行dump
- 如果不知道本机ip地址，可以使用0.0.0.0，这样ip地址会绑定主机ip。
append=true：是执行数据文件已经存在，则覆盖数据将附加到现有文件。

页面或接口调用

调用接口http://localhost:8080/user/getUser?id=1

4、cli 包 dump 生成 exec 文件（注意一定要测试完毕之后）

$ java -jar jacococli.jar dump --address localhost --port 6300 --destfile jacoco-demo.exec
[INFO] Connecting to localhost/127.0.0.1:6300.
[INFO] Writing execution data to E:\gitcode\mygit\learn\jacoco\jacoco-demo\target\jacoco-demo.exec.

--address localhost --port 6300 指向jacocoagent启动IP和端口
jacoco-demo.exec 为生成exec文件名

5、生成report

$ java -jar jacococli.jar report jacoco-demo.exec --classfiles E:/gitcode/mygit/learn/jacoco/jacoco-demo/target/classes --sourcefiles E:/gitcode/mygit/learn/jacoco/jacoco-demo/src/main/java --html html-report --xml report.xml --encoding=utf-8
[INFO] Loading execution data file E:\gitcode\mygit\learn\jacoco\jacoco-demo\target\jacoco-demo.exec.
[INFO] Analyzing 4 classes.

--sourcefiles 和 --classfiles 为本地被测项目源码和字节码路径。
--html 为生成报告目录。

6、查看覆盖率报告

表格

Element：元素；
Missed Instructions Cov：未覆盖字节码行数；
Missed Branches Cov：未覆盖的分支数；
Cxty：圈复杂度；
Lines：行；
Methods：方法；
Classes：类；

覆盖率标识

条件覆盖：红钻：表示未覆盖；黄钻：表示部分覆盖；绿钻：表示全部覆盖；
行覆盖：全覆盖（绿色），未覆盖（红色），半覆盖（黄色），无视（白色）

只调用http://localhost:8080/user/getUser?id=1，效果如下

调用如下接口

http://localhost:8080/user/getUser?id=1、http://localhost:8080/user/getUser?id=2、http://localhost:8080/user/getUser?id=3、http://localhost:8080/user/getUser?id=5

效果如下，覆盖率为100%：