D:\>mvn -version
Usage: java [-options] class [args...]
(to execute a class)
or java [-options] -jar jarfile [args...]
(to execute a jar file)
where options include:
-d32 use a 32-bit data model if available
-d64 use a 64-bit data model if available
-server to select the "server" VM
The default VM is server.
-cp <class search path of directories and zip/jar files>
-classpath <class search path of directories and zip/jar files>
A ; separated list of directories, JAR archives,
and ZIP archives to search for class files.
-D<name>=<value>
set a system property
-verbose:[class|gc|jni]
enable verbose output
-version print product version and exit
-version:<value>
Warning: this feature is deprecated and will be removed
in a future release.
require the specified version to run
-showversion print product version and continue
-jre-restrict-search | -no-jre-restrict-search
Warning: this feature is deprecated and will be removed
in a future release.
include/exclude user private JREs in the version search
-? -help print this help message
-X print help on non-standard options
-ea[:<packagename>...|:<classname>]
-enableassertions[:<packagename>...|:<classname>]
enable assertions with specified granularity
-da[:<packagename>...|:<classname>]
-disableassertions[:<packagename>...|:<classname>]
disable assertions with specified granularity
-esa | -enablesystemassertions
enable system assertions
-dsa | -disablesystemassertions
disable system assertions
-agentlib:<libname>[=<options>]
load native agent library <libname>, e.g. -agentlib:hprof
see also, -agentlib:jdwp=help and -agentlib:hprof=help
-agentpath:<pathname>[=<options>]
load native agent library by full pathname
-javaagent:<jarpath>[=<options>]
load Java programming language agent, see java.lang.instrument
-splash:<imagepath>
show splash screen with specified image
有关更多详细信息，请参见http://www.oracle.com/technetwork/java/javase/documentation/index.html。
D：> java 用法：java [-options]类[args ...] （执行一个类）
从用户文件夹提供适当的版本。在其他文件夹中不起作用。
环境变量设置正确。 MAVEN_HOME D：\ apache-maven-3.3.9 M2 D：\ apache-maven-3.3.9 \ bin 路径：％M2％
C:\Users\P1321000>mvn -version
Apache Maven 3.3.9 (bb52d8502b132ec0a5a3f4c09453c07478323dc5; 2015-11-11T00:41:47+08:00)
Maven home: D:\apache-maven-3.3.9\bin\..
Java version: 1.8.0_191, vendor: Oracle Corporation
Java home: C:\Program Files\Java\jdk1.8.0_191\jre
Default locale: en_US, platform encoding: Cp1252
OS name: "windows 10", version: "10.0", arch: "amd64", family: "dos"