echo %JAVA_HOME%
C:\Program Files\Java\jdk1.8.0_211


java -version
mvn -version   查看mvn 和 java信息 
set JAVA_HOME=D:\dugang\soft\openjdk17\jdk17
注意后面不要有空格， 执行mvn会报错
mvn -v
The JAVA_HOME environment variable is not defined correctly,
this environment variable is needed to run this program.

where java


echo %JAVA_HOME%
C:\Program Files\Java\jdk1.8.0_211

java -version
java version "1.8.0_211"
Java(TM) SE Runtime Environment (build 1.8.0_211-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.211-b12, mixed mode)

mvn -version
Apache Maven 3.8.4 (9b656c72d54e5bacbed989b64718c159fe39b537)
Maven home: D:\dugang\soft\mvn3
Java version: 1.8.0_211, vendor: Oracle Corporation, runtime: C:\Program Files\Java\jdk1.8.0_211\jre
Default locale: zh_CN, platform encoding: GBK
OS name: "windows 10", version: "10.0", arch: "amd64", family: "windows"

where java
C:\Program Files\Java\jdk1.8.0_211\jre\bin\java.exe