macOS，当前文件夹

Java 13在macOS Mojave…

如果所有的.jar文件都在同一个文件夹中，使用cd将其设置为当前工作目录。与pwd核实。

对于-classpath，首先必须列出应用程序的JAR文件。使用冒号:作为分隔符，附加星号*以获得同一文件夹中的所有其他JAR文件。最后，将类的完整包名与main方法一起传递。

例如，对于一个名为my_app.jar的JAR文件中的一个应用程序，在一个名为com的包中一个名为app的类中有一个主方法。例如，在同一个文件夹中放置一些需要的罐子:

java -classpath my_app.jar:* com.example.App

我知道的唯一方法是单独做，例如:

setenv CLASSPATH /User/username/newfolder/jarfile.jar:jarfile2.jar:jarfile3.jar:.

希望有帮助!

简写形式:如果你的main在一个jar中，你可能需要一个额外的“-jar pathTo/yourJar/YourJarsName.jar”显式声明来让它工作(即使“YourJarsName.jar”在类路径中) (或者，回答5年前提出的原始问题:你不需要显式地重新声明每个jar，但看起来，即使在java6中，你也需要重新声明自己的jar…)

长形式: (我已经明确说明了这一点，我希望即使是java的闯入者也可以使用它)

像这里的许多人一样，我使用eclipse导出JAR:(File-> export ->'可运行的JAR文件')。eclipse (Juno)提供了三个“库处理”选项:

opt1: "Extract required libraries into generated JAR"
opt2: "Package required libraries into generated JAR"
opt3: "Copy required libraries into a sub-folder next to the generated JAR"

通常我会使用opt2 (opt1肯定会破坏)，但是我正在使用的一个jar中的本机代码，当您选择该选项时，我发现eclipse利用了方便的“jarinjar”技巧。即使在意识到我需要opt3之后，然后找到这个StackOverflow条目，我仍然花了一些时间来弄清楚如何在eclipse之外启动我的main，所以这里是对我有用的，因为它对其他人很有用……

如果你将罐子命名为fooBarTheJarFile.jar 和所有设置导出到目录:“/theFully/qualifiedPath/toYourChosenDir”。

(意味着“导出目的地”字段将读取:“/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile.jar”)

当你点击finish后，你会发现eclipse将所有的库放在一个名为“fooBarTheJarFile_lib”的文件夹中，就像这样:

/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile.jar
/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile_lib/SomeOtherJar01.jar
/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile_lib/SomeOtherJar02.jar
/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile_lib/SomeOtherJar03.jar
/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile_lib/SomeOtherJar04.jar

然后，您可以从系统上的任何地方启动:

java -classpath "/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile_lib/*" -jar  /theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile.jar   package.path_to.the_class_with.your_main.TheClassWithYourMain

(对于Java新手来说:` package.path_to.the_class_with. path `。your_main'是声明的包路径，你可以在' classwithyourmain .java'文件的顶部找到，该文件包含'main(String[] args){…}'你希望在java之外运行)

要注意的陷阱:在你声明的类路径上的jar列表中有'fooBarTheJarFile.jar'是不够的。您需要显式地声明'-jar'，并重新声明该jar的位置。

例如:

 java -classpath "/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile.jar;/theFully/qualifiedPath/toYourChosenDir/fooBarTheJarFile_lib/*"  somepackages.inside.yourJar.leadingToTheMain.TheClassWithYourMain

用相对路径重申:

cd /theFully/qualifiedPath/toYourChosenDir/;
BREAKS:  java -cp "fooBarTheJarFile_lib/*"                                package.path_to.the_class_with.your_main.TheClassWithYourMain    
BREAKS:  java -cp ".;fooBarTheJarFile_lib/*"                              package.path_to.the_class_with.your_main.TheClassWithYourMain   
BREAKS:  java -cp ".;fooBarTheJarFile_lib/*"   -jar                       package.path_to.the_class_with.your_main.TheClassWithYourMain   
WORKS:   java -cp ".;fooBarTheJarFile_lib/*"   -jar  fooBarTheJarFile.jar package.path_to.the_class_with.your_main.TheClassWithYourMain   

(使用Java版本“1.6.0_27”;通过OpenJDK 64位服务器虚拟机安装在ubuntu 12.04上)

使用Java 6或更高版本，类路径选项支持通配符。注意事项:

使用直引号(") 使用*，而不是*.jar

窗户

lib/*" my.package.MainClass . java -cp "Test.jar

Unix

java -cp "Test.jar:lib/*" my.package.MainClass .jar:lib/*

这类似于Windows，但使用:而不是;。如果你不能使用通配符，bash允许以下语法(其中lib是包含所有Java存档文件的目录):

Java -cp "$(printf %s: lib/*.jar)"

(注意，使用类路径与-jar选项不兼容。参见:从命令提示符执行带有多个类路径库的jar文件)

理解通配符

从类路径文档中:

Class path entries can contain the basename wildcard character *, which is considered equivalent to specifying a list of all the files in the directory with the extension .jar or .JAR. For example, the class path entry foo/* specifies all JAR files in the directory named foo. A classpath entry consisting simply of * expands to a list of all the jar files in the current directory. A class path entry that contains * will not match class files. To match both classes and JAR files in a single directory foo, use either foo;foo/* or foo/*;foo. The order chosen determines whether the classes and resources in foo are loaded before JAR files in foo, or vice versa. Subdirectories are not searched recursively. For example, foo/* looks for JAR files only in foo, not in foo/bar, foo/baz, etc. The order in which the JAR files in a directory are enumerated in the expanded class path is not specified and may vary from platform to platform and even from moment to moment on the same machine. A well-constructed application should not depend upon any particular order. If a specific order is required then the JAR files can be enumerated explicitly in the class path. Expansion of wildcards is done early, prior to the invocation of a program's main method, rather than late, during the class-loading process itself. Each element of the input class path containing a wildcard is replaced by the (possibly empty) sequence of elements generated by enumerating the JAR files in the named directory. For example, if the directory foo contains a.jar, b.jar, and c.jar, then the class path foo/* is expanded into foo/a.jar;foo/b.jar;foo/c.jar, and that string would be the value of the system property java.class.path. The CLASSPATH environment variable is not treated any differently from the -classpath (or -cp) command-line option. That is, wildcards are honored in all these cases. However, class path wildcards are not honored in the Class-Path jar-manifest header.

注意:由于java 8中的一个已知错误，windows示例必须在条目前使用反斜杠，后面带星号:https://bugs.openjdk.java.net/browse/JDK-8131329

简单回答:java -classpath lib/*:。my.package.Program

Oracle提供了关于在Java 6和Java 7的类路径中使用通配符的文档，在“理解类路径通配符”一节中。(在我写这篇文章的时候，这两页的内容是一样的。)以下是此次会议的重点总结:

In general, to include all of the JARs in a given directory, you can use the wildcard * (not *.jar). The wildcard only matches JARs, not class files; to get all classes in a directory, just end the classpath entry at the directory name. The above two options can be combined to include all JAR and class files in a directory, and the usual classpath precedence rules apply. E.g. -cp /classes;/jars/* The wildcard will not search for JARs in subdirectories. The above bullet points are true if you use the CLASSPATH system property or the -cp or -classpath command line flags. However, if you use the Class-Path JAR manifest header (as you might do with an ant build file), wildcards will not be honored.

是的，我的第一个链接与得分最高的答案中提供的链接相同(我没有希望超越它)，但这个答案并没有提供更多的解释。由于现在Stack Overflow不鼓励这种行为，我想我应该对此进行扩展。

java命令的参数顺序也很重要:

c:\projects\CloudMirror>java Javaside -cp "jna-5.6.0.jar;.\"
Error: Unable to initialize main class Javaside
Caused by: java.lang.NoClassDefFoundError: com/sun/jna/Callback

与

c:\projects\CloudMirror>java -cp "jna-5.6.0.jar;.\" Javaside
Exception in thread "main" java.lang.UnsatisfiedLinkError: Unable