| 知乎专栏 |
参数 说明 -l 输出主类全名或jar路径 -q 只输出LVMID -m 输出JVM启动时传递给main()的参数 -v 输出JVM启动时显示指定的JVM参数
neo@MacBook-Pro-M2 ~> jps 6560 Jps 6273 Launcher 6274 TestThread 88034 Eclipse 6404 XMLServerLauncher 97828 org.eclipse.equinox.launcher_1.6.400.v20210924-0641.jar 1176 2891 98015 BootLanguageServerBootApp neo@MacBook-Pro-M2 ~> jps -m 6273 Launcher /Applications/IntelliJ IDEA CE.app/Contents/plugins/java/lib/jps-builders.jar:/Applications/IntelliJ IDEA CE.app/Contents/plugins/java/lib/jps-builders-6.jar:/Applications/IntelliJ IDEA CE.app/Contents/plugins/java/lib/jps-javac-extension.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/util.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/util-8.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/util_rt.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/annotations.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/3rd-party-rt.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/protobuf.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/jps-model.jar:/Applications/IntelliJ IDEA CE.app/Contents/plugins/java/lib/javac2.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/forms_rt.jar:/Applications/IntelliJ IDEA CE.app/Contents/plugins/java/lib/aether-dependency-resolver.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/idea_rt.jar:/Applications/IntelliJ IDEA CE.ap 6274 TestThread 6562 Jps -m 88034 Eclipse 6404 XMLServerLauncher 97828 org.eclipse.equinox.launcher_1.6.400.v20210924-0641.jar -configuration /Users/neo/Library/Application Support/Code/User/globalStorage/redhat.java/1.17.0/config_mac -data /Users/neo/Library/Application Support/Code/User/workspaceStorage/c0c3760503bc4a3db6b66b0155e50c5b/redhat.java/jdt_ws 1176 2891 98015 BootLanguageServerBootApp neo@MacBook-Pro-M2 ~> jps -l 6273 org.jetbrains.jps.cmdline.Launcher 6274 cn.netkiller.TestThread 88034 Eclipse 6564 jdk.jcmd/sun.tools.jps.Jps 6404 org.eclipse.lemminx.XMLServerLauncher 97828 /Users/neo/.vscode/extensions/redhat.java-1.17.0-darwin-arm64/server/plugins/org.eclipse.equinox.launcher_1.6.400.v20210924-0641.jar 1176 2891 98015 org.springframework.ide.vscode.boot.app.BootLanguageServerBootApp
查看包中的文件列表 jar -tf package.war/package.jar
$ /srv/java/bin/jar -tf mis.netkiller.cn-0.0.1.war |more META-INF/ META-INF/MANIFEST.MF WEB-INF/ WEB-INF/jsp/ WEB-INF/jsp/include/ WEB-INF/jsp/system/ WEB-INF/jsp/banner/
包类依赖分析器
[net@netkiller lib]$ jdeps jersey-client-1.18.1.jar
jersey-client-1.18.1.jar -> not found
jersey-client-1.18.1.jar -> /usr/java/jdk1.8.0_73/jre/lib/rt.jar
com.sun.jersey.api.client (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client.async jersey-client-1.18.1.jar
-> com.sun.jersey.api.client.config jersey-client-1.18.1.jar
-> com.sun.jersey.api.client.filter jersey-client-1.18.1.jar
-> com.sun.jersey.client.impl jersey-client-1.18.1.jar
-> com.sun.jersey.client.impl.async jersey-client-1.18.1.jar
-> com.sun.jersey.client.proxy jersey-client-1.18.1.jar
-> com.sun.jersey.client.urlconnection jersey-client-1.18.1.jar
-> com.sun.jersey.core.header not found
-> com.sun.jersey.core.provider not found
-> com.sun.jersey.core.reflection not found
-> com.sun.jersey.core.spi.component not found
-> com.sun.jersey.core.spi.component.ioc not found
-> com.sun.jersey.core.spi.factory not found
-> com.sun.jersey.core.util not found
-> com.sun.jersey.spi not found
-> com.sun.jersey.spi.inject not found
-> com.sun.jersey.spi.service not found
-> java.io
-> java.lang
-> java.lang.annotation
-> java.lang.reflect
-> java.net
-> java.util
-> java.util.concurrent
-> java.util.logging
-> javax.ws.rs.core not found
-> javax.ws.rs.ext not found
com.sun.jersey.api.client.async (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client jersey-client-1.18.1.jar
-> java.lang
-> java.util.concurrent
com.sun.jersey.api.client.config (jersey-client-1.18.1.jar)
-> com.sun.jersey.core.util not found
-> java.lang
-> java.util
com.sun.jersey.api.client.filter (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client jersey-client-1.18.1.jar
-> com.sun.jersey.core.util not found
-> java.io
-> java.lang
-> java.net
-> java.nio.charset
-> java.security
-> java.util
-> java.util.logging
-> java.util.regex
-> java.util.zip
-> javax.ws.rs not found
-> javax.ws.rs.core not found
com.sun.jersey.client.impl (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client jersey-client-1.18.1.jar
-> com.sun.jersey.core.header not found
-> java.io
-> java.lang
-> java.net
-> java.util
-> java.util.concurrent.atomic
-> javax.ws.rs.core not found
com.sun.jersey.client.impl.async (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client jersey-client-1.18.1.jar
-> com.sun.jersey.api.client.async jersey-client-1.18.1.jar
-> java.lang
-> java.util.concurrent
com.sun.jersey.client.proxy (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client jersey-client-1.18.1.jar
-> com.sun.jersey.api.client.async jersey-client-1.18.1.jar
-> java.lang
-> java.util.concurrent
com.sun.jersey.client.urlconnection (jersey-client-1.18.1.jar)
-> com.sun.jersey.api.client jersey-client-1.18.1.jar
-> com.sun.jersey.core.header not found
-> com.sun.jersey.spi not found
-> java.io
-> java.lang
-> java.lang.reflect
-> java.net
-> java.security
-> java.util
-> java.util.logging
-> javax.net.ssl
-> javax.ws.rs.core not found
com.sun.ws.rs.ext (jersey-client-1.18.1.jar)
-> com.sun.jersey.core.spi.factory not found
-> java.lang
-> javax.ws.rs.core not found
JShell，即 Java Shell。从java9开始，java开始引入了 REPL（Read-Eval-Print Loop，读取-求值-输出 循环）工具
neo@MacBook-Pro ~ % jshell | Welcome to JShell -- Version 12 | For an introduction type: /help intro jshell>
jshell> /help | Type a Java language expression, statement, or declaration. | Or type one of the following commands: | /list [<name or id>|-all|-start] | list the source you have typed | /edit <name or id> | edit a source entry | /drop <name or id> | delete a source entry | /save [-all|-history|-start] <file> | Save snippet source to a file | /open <file> | open a file as source input | /vars [<name or id>|-all|-start] | list the declared variables and their values | /methods [<name or id>|-all|-start] | list the declared methods and their signatures | /types [<name or id>|-all|-start] | list the type declarations | /imports | list the imported items | /exit [<integer-expression-snippet>] | exit the jshell tool | /env [-class-path <path>] [-module-path <path>] [-add-modules <modules>] ... | view or change the evaluation context | /reset [-class-path <path>] [-module-path <path>] [-add-modules <modules>]... | reset the jshell tool | /reload [-restore] [-quiet] [-class-path <path>] [-module-path <path>]... | reset and replay relevant history -- current or previous (-restore) | /history [-all] | history of what you have typed | /help [<command>|<subject>] | get information about using the jshell tool | /set editor|start|feedback|mode|prompt|truncation|format ... | set configuration information | /? [<command>|<subject>] | get information about using the jshell tool | /! | rerun last snippet -- see /help rerun | /<id> | rerun snippets by ID or ID range -- see /help rerun | /-<n> | rerun n-th previous snippet -- see /help rerun | | For more information type '/help' followed by the name of a | command or a subject. | For example '/help /list' or '/help intro'. | | Subjects: | | intro | an introduction to the jshell tool | keys | a description of readline-like input editing | id | a description of snippet IDs and how use them | shortcuts | a description of keystrokes for snippet and command completion, | information access, and automatic code generation | context | a description of the evaluation context options for /env /reload and /reset | rerun | a description of ways to re-evaluate previously entered snippets
介绍信息
jshell> /help intro | | intro | ===== | | The jshell tool allows you to execute Java code, getting immediate results. | You can enter a Java definition (variable, method, class, etc), like: int x = 8 | or a Java expression, like: x + x | or a Java statement or import. | These little chunks of Java code are called 'snippets'. | | There are also the jshell tool commands that allow you to understand and | control what you are doing, like: /list | | For a list of commands: /help
使用 jlink 定自己的 jre
jlink --module-path jmods --add-modules java.desktop --output /tmp/jre-16.0.2
查看输出结果
neo@MacBook-Pro-Neo ~ % ll /tmp/jre-16.0.2 total 8 drwxr-xr-x 4 neo wheel 128B 8 31 15:08 bin drwxr-xr-x 5 neo wheel 160B 8 31 15:08 conf drwxr-xr-x 8 neo wheel 256B 8 31 15:08 include drwxr-xr-x 7 neo wheel 224B 8 31 15:08 legal drwxr-xr-x 38 neo wheel 1.2K 8 31 15:08 lib drwxr-xr-x 3 neo wheel 96B 8 31 15:08 man -rw-r--r-- 1 neo wheel 93B 8 31 15:08 release
查看 release 文件
neo@MacBook-Pro-Neo ~ % cat /tmp/jre-16.0.2/release JAVA_VERSION="16.0.2" MODULES="java.base java.datatransfer java.xml java.prefs java.desktop"