Java在命令提示符下运行程序:找不到或加载主类

Question

我正在尝试学习如何在Windows中仅使用命令行进行编译和运行.这是从根开始的目录树:

D:
 ActivityOne
     - classes
         - com
           -wat
             -sampleapp
                -students
                    StudentE.class
                 StudentMasterList.class (Main)
     - src
         -com
           -wat
             -sampleapp
                -students
                    StudentE.java
                 StudentMasterList.java (Main)

问题是我现在对如何运行程序感到困惑.我尝试了两件事,两件事都返回了不同的错误.

第一次尝试:

java -classpath classes StudentMasterList

回:

Error: Could not find or load main class StudentMasterList

第二次尝试:

java -classpath classes/com/wat/sampleapp StudentMasterList

回:

Exception in thread "main" java.lang.NoClassDefFoundError: StudentMasterList (wrongname: com/wat/sam
pleapp/StudentMasterList)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

我在下次尝试后感到困惑,对于我应该如何运行主类的任何帮助？

更新:我应该在该ActivityOne级别运行所有命令.

Answer 1

正确的方法是

java -classpath D:\ActivityOne\classes com.wat.sampleapp.StudentMasterList

换句话说,您将顶级目录添加到类路径,然后使用Java类的完全限定名称.