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Java Java Objects Harnessing the Power of Objects Exceptions

Posted by Sayan Karmakar
Sayan Karmakar
636 Points

Example.java

Error: Could not find or load main class Example.java
I don't understand why this is happening. Please help!

Mihai Craciun
Mihai Craciun
13,520 Points
Mihai Craciun
Mihai Craciun
13,520 Points

Reason #1 - you made a mistake with the classname argument

The first likely cause is that you may have provided the wrong class name. (Or ... the right class name, but in the wrong form.)

Reason #2 - the application's classpath is incorrectly specified

The second likely cause is that the class name is correct, but that the java command cannot find the class. To understand this, you need to understand the concept of the "classpath" (check Oracle Documentation)

Reason #3 - the class has been declared in the wrong package

It occasionally happens that someone puts a source code file into the the wrong folder in their source code tree, or they leave out the package declaration. If you do this in an IDE, the IDE's compiler will tell you about this immediately. Similarly if you use a decent Java build tool, the tool will run javac in a way that will detect the problem. However, if you build your Java code by hand, you can do it in such a way that the compiler doesn't notice the problem, and the resulting ".class" file is not in the place that you expect it to be.