C:\Users\Lilibo>java -version java version "1.6.0_23" Java(TM) SE Runtime Environment (build 1.6.0_23-b05) Java HotSpot(TM) Client VM (build 19.0-b09, mixed mode, sharing)
C:\Users\Lilibo>java Usage: java [-options] class [args...] (to execute a class) or java [-options] -jar jarfile [args...] (to execute a jar file) where options include: -client to select the "client" VM -server to select the "server" VM -hotspot is a synonym for the "client" VM [deprecated] The default VM is client. -cp -classpath A ; separated list of directories, JAR archives, and ZIP archives to search for class files. -D = set a system property -verbose[:class|gc|jni] enable verbose output -version print product version and exit -version: require the specified version to run -showversion print product version and continue -jre-restrict-search | -jre-no-restrict-search include/exclude user private JREs in the version search -? -help print this help message -X print help on non-standard options -ea[: ...|: ] -enableassertions[: ...|: ] enable assertions -da[: ...|: ] -disableassertions[: ...|: ] disable assertions -esa | -enablesystemassertions enable system assertions -dsa | -disablesystemassertions disable system assertions -agentlib: [= ] load native agent library , e.g. -agentlib:hprof see also, -agentlib:jdwp=help and -agentlib:hprof=help -agentpath: [= ] load native agent library by full pathname -javaagent: [= ] load Java programming language agent, see java.lang.instrument -splash: show splash screen with specified image
2、进入/etc/目录(cd /etc/)使用vi工具编辑profile文件(使用 vi profile 命令进入编辑器命令模式，输入"i"开始插入内容，将光标移动至目标位置，输入完毕之后按Esc退出编辑模式回到命令模式，命令模式下输入":wq!"保存退出)，在末尾输入如下内容(Linux系统中的分隔符为":")：
appuser@usm:~> java -version java version "1.6.0_17" Java(TM) SE Runtime Environment (build 1.6.0_17-b04) Java HotSpot(TM) 64-Bit Server VM (build 14.3-b01, mixed mode) appuser@usm:~>
appuser@usm:~> java 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 -classpath A : separated list of directories, JAR archives, and ZIP archives to search for class files. -D = set a system property -verbose[:class|gc|jni] enable verbose output -version print product version and exit -version: require the specified version to run -showversion print product version and continue -jre-restrict-search | -jre-no-restrict-search include/exclude user private JREs in the version search -? -help print this help message -X print help on non-standard options -ea[: ...|: ] -enableassertions[: ...|: ] enable assertions -da[: ...|: ] -disableassertions[: ...|: ] disable assertions -esa | -enablesystemassertions enable system assertions -dsa | -disablesystemassertions disable system assertions -agentlib: [= ] load native agent library , e.g. -agentlib:hprof see also, -agentlib:jdwp=help and -agentlib:hprof=help -agentpath: [= ] load native agent library by full pathname -javaagent: [= ] load Java programming language agent, see java.lang.instrument -splash: show splash screen with specified image appuser@usm:~>
appuser@usm:~> javac Usage: javac where possible options include: -g Generate all debugging info -g:none Generate no debugging info -g:{lines,vars,source} Generate only some debugging info -nowarn Generate no warnings -verbose Output messages about what the compiler is doing -deprecation Output source locations where deprecated APIs are used -classpath Specify where to find user class files and annotation processors -cp Specify where to find user class files and annotation processors -sourcepath Specify where to find input source files -bootclasspath Override location of bootstrap class files -extdirs Override location of installed extensions -endorseddirs Override location of endorsed standards path -proc:{none,only} Control whether annotation processing and/or compilation is done. -processor [, , ...]Names of the annotation processors to run; bypasses default discovery process -processorpath Specify where to find annotation processors -d Specify where to place generated class files -s Specify where to place generated source files -implicit:{none,class} Specify whether or not to generate class files for implicitly referenced files -encoding Specify character encoding used by source files -source Provide source compatibility with specified release -target Generate class files for specific VM version -version Version information -help Print a synopsis of standard options -Akey[=value] Options to pass to annotation processors -X Print a synopsis of nonstandard options -J Pass directly to the runtime system appuser@usm:~>