java 即使jar文件在工作目录中也找不到类
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Cannot find class even when jar file is in working directory
提问by Michael Sandler
I am struggling to get my Java program to run on AIX. I used Eclipse on Windows to create a runnable Jar file, jRams.jarbelow. I kept on getting a class not found error, until finally I put all the external libraries in the same directory.
我正在努力让我的 Java 程序在 AIX 上运行。我在 Windows 上使用 Eclipse 创建了一个可运行的 Jar 文件，jRams.jar如下所示。我不断收到未找到类的错误，直到最后我将所有外部库都放在同一目录中。
$ ls
JAXB2_20081030.jar
JAXB2_20110601.jar
activation.jar
asjava.jar
commons-beanutils-1.8.3.jar
commons-beanutils-bean-collections-1.8.3.jar
commons-beanutils-core-1.8.3.jar
commons-codec-1.5.jar
commons-collections-3.2.1.jar
commons-configuration-1.6.jar
commons-digester-2.1.jar
commons-jxpath-1.3.jar
commons-lang-2.6.jar
commons-logging-1.1.1.jar
commons-logging-adapters-1.1.1.jar
commons-logging-api-1.1.1.jar
jRams.jar
jaxb-api.jar
jaxb-impl.jar
jaxb-xjc.jar
jaxb1-impl.jar
jremote.jar
jsr173_1.0_api.jar
log4j-1.2.16.jar
netty-3.2.4.Final.jar
$
Still, I get the class not found error.
尽管如此，我还是收到了未找到类的错误。
$ java -jar jRams.jar
The java class is not found: com.jbase.jremote.JRemoteException
jremote.jardefinitely contains JRemoteException. Why isn't this working?
jremote.jar肯定包含JRemoteException。为什么这不起作用？
UPDATE
更新
Thank you for your straight-to-the-point answers. I now understand the nature of a java application and a manifest file far better.
感谢您的直截了当的回答。我现在更好地理解了 Java 应用程序和清单文件的性质。
Turns out my ftp client was transferring in ASCII mode and not Binary, so the jar files were corrupt. I have learned a great deal, nonetheless.
结果我的 ftp 客户端以 ASCII 模式传输而不是二进制模式，所以 jar 文件已损坏。尽管如此，我还是学到了很多东西。
回答by aioobe
When using the -jaroption, you need to specify which jar-files should be on your class path in the manifest file. Just having the required jar files in the same directory won't do it.
使用该-jar选项时，您需要指定清单文件中的类路径上应包含哪些 jar文件。仅将所需的 jar 文件放在同一目录中是行不通的。
Add a line in your manifest that says:
在清单中添加一行内容：
Class-Path: JAXB2_20081030.jar:JAXB2_20110601.jar:....:netty-3.2.4.Final.jar
or skip the -jaroption and launch using
或跳过该-jar选项并使用
java -cp JAXB2_20081030.jar:....:netty-3.2.4.Final.jar:jRams.jar pkg.JRamsMain
and it should work fine.
它应该可以正常工作。
(Note that on *nix systems, as opposed to Windows machines, the jar files in the class paths should be separated using :instead of ;.)
（请注意，在 *nix 系统上，与 Windows 机器相反，类路径中的 jar 文件应使用:代替来分隔;。）
Further reading:
进一步阅读：
回答by duffymo
You need to add all those JARs to the runtime CLASSPATHby adding the -classpathparameter. AIX requires you to separate the JARs using :
您需要CLASSPATH通过添加-classpath参数将所有这些 JAR 添加到运行时。AIX 要求您使用:
回答by Bitmap
You will have to specify the full path(if libraries not in the same directory as jRams) or just the names of the jar file in a manifest file (If all dependency jars are in the same folder). Alternative specify the path to all the dependent jarsusing -cpargument.
您必须指定完整路径（如果库与 不在同一目录中jRams）或仅在清单文件中指定 jar 文件的名称（如果所有依赖 jar 都在同一文件夹中）。替代方法使用参数指定所有依赖jar的路径-cp。
Example(This assume every dependency is in the same directory you are executing java command from):
示例（假设每个依赖项都在您从中执行 java 命令的同一目录中）：
java -cp commons-collections-3.2.1.jar; jaxb-impl.jar; etc.. ;jRams.jar package_to_class.MyMainClass.java
java -cp commons-collections-3.2.1.jar; jaxb-impl.jar; etc.. ;jRams.jar package_to_class.MyMainClass.java
Where package_to_classis example: com.myproj.example.
package_to_class示例在哪里：com.myproj.example。
EDITED.
已编辑。
