Getting Started with Java-class HelloWorld is public and should be declared in a file named Helloworld.java

Started to learn Java, set up a good environment, notepad++ a new Java file, create a new HelloWorld class,

 Public class helloworld{    publicstaticvoid  main (string[] args)    {        System.out.println ("Hello world!" );    }}

Save the file named Firstjava.java, and then go to the command line to start compiling, but there is an error at compile time, "class HelloWorld is public, should be declared in a file named Helloworld.java".

Solution: In fact, the hint has been very obvious, Java source code filename is wrong, should be consistent with the class of the declaration, the Firstjava.java will be changed to Helloworld.java on it.

Getting Started with Java-class HelloWorld is public and should be declared in a file named Helloworld.java