.jar错误 - 无法找到或加载主类 [英] .jar error - could not find or load main class

问题描述

我尝试将HelloWorld放在.jar文件中并运行它，但它不起作用。我创建了java文件并输入了程序，然后在cmd中写道：

I tried to put HelloWorld in a .jar file and running it, but it doesn't work. I created the java file and typed in the program, and then wrote in cmd:

javac HelloWorld.java
java HelloWorld

并且有效。然后我输入

echo Main-Class: HelloWorld >manifest.txt
jar cvfm HelloWorld.jar manifest.txt HelloWorld.class

并获得输出

added manifest
adding: HelloWorld.class(in = 426) (out= 288)(deflated 32%)

然后我输入

java -jar HelloWorld.jar
HelloWorld.jar

并且第一行有效，而第二行给了我一个错误：

and the first line worked, while the second line gave me an error:

Error: Could not find or load main class path\HelloWorld.jar

当我尝试用64位jre7 \ bin中的java.exe文件打开它时，我得到的输出（在一个快速关闭的窗口中） ，jdk1.7.0_51 \ bin，jdk1.7.0_51 \ jre \ bin，以及32位jre7 \ bin。我已经卸载并重新安装了我的jre和jdk并重新创建了我的.class和.jar文件，但问题仍然存在。我在win8上。

which is the same output I got (in a rapidly closing window) when I tried to open it with the java.exe file in 64 bit jre7\bin, jdk1.7.0_51\bin, jdk1.7.0_51\jre\bin, as well as 32 bit jre7\bin. I've uninstalled and reinstalled both my jre and jdk and recreated my .class and .jar files, but the problem persists. I'm on win8.

编辑：我试图像aetheria那样建议，但没有运气。我把HelloWorld.java放在path \comcom \stackoverflow \ user \ blrp中，编译它，然后输入

I tried to do as aetheria suggested, but no luck. I put HelloWorld.java in path\com\stackoverflow\user\blrp, compiled it, and it worked by entering

java com.stackoverflow.user.blrp.HelloWorld

在路径中。然后我创建了清单和jar：

in path. I then created the manifest and jar by:

(echo Manifest-Version: 1.0
echo Class-Path: .
echo Main-Class: com.stackoverflow.user.blrp.HelloWorld) >manifest.txt
jar cvfm HelloWorld.jar manifest.txt com\stackoverflow\user\blrp\HelloWorld.class

并获得输出

added manifest
adding: com/stackoverflow/user/blrp/HelloWorld.class(in = 454) (out= 312)(deflat
ed 31%)

但是，java -jar HelloWorld.jar工作且HelloWorld.jar没有（同样的错误）。我也尝试过不做包装的东西，只是清单中的Class-Path，结果相同。

but still, java -jar HelloWorld.jar worked and HelloWorld.jar didn't (same error). I also tried not doing the package thing, just the Class-Path in manifest, same result.

（另外，我在使用问题提出问题之前解决了问题一个.bat文件，但让那个jar工作仍然很好。）

(Also, I solved the problem prior to asking the question by use of a .bat file, but it'd still be sweet to get that jar working.)

推荐答案

感谢jbaliuka的建议。我打开注册表编辑器（通过在cmd中键入regedit）并转到HKEY_CLASSES_ROOT> jarfile> shell> open>命令，然后打开（默认）并更改值

Thanks jbaliuka for the suggestion. I opened the registry editor (by typing regedit in cmd) and going to HKEY_CLASSES_ROOT > jarfile > shell > open > command, then opening (Default) and changing the value from

C：\Program Files\Java\jre7\bin\javaw.exe-jar％1％*

到

C：\Program Files\Java \ jre7 \ bin \ java。 exe-jar％1％*

（我刚删除了javaw.exe中的w。）之后你必须要正确单击一个jar - >打开 - >选择默认程序 - >导航到您的java文件夹并打开\ jre7\bin\java.exe（或您java文件夹中的任何其他java.exe文件）。如果它不起作用，请尝试切换到javaw.exe，用它打开一个jar文件，然后切换回来。

(I just removed the w in javaw.exe.) After that you have to right click a jar -> open with -> choose default program -> navigate to your java folder and open \jre7\bin\java.exe (or any other java.exe file in you java folder). If it doesn't work, try switching to javaw.exe, open a jar file with it, then switch back.

我对编辑注册表一无所知除了它是危险的，所以你可能想要在做这个之前备份它（在顶部栏，文件>导出）。

I don't know anything about editing the registry except that it's dangerous, so you might wanna back it up before doing this (in the top bar, File>Export).

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