Java Tutorial/Language/Main
Содержание
Display all command-line arguments.
<source lang="java">
class CommandLine {
public static void main(String args[]) { for (int i = 0; i < args.length; i++) System.out.println("args[" + i + "]: " + args[i]); }
}</source>
New parameter for main method
<source lang="java">
public class Main {
public static void main(String... args) { for (String arg : args) { System.out.println(arg); } }
}</source>
The Method main
- A special method called main provides the entry point to an application.
- An application can have many classes and only one of the classes needs to have the method main.
- This method allows the class containing it to be invoked.
The signature of the method main is as follows.
<source lang="java">
public class MainClass {
public static void main(String[] args) { }
}</source>
All arguments must be passed as strings. For instance, to pass two arguments, "1" and "mode" when running the Test class, you type this:
java Test 1 mode
Throw Exception through main method
<source lang="java">
public class MainClass {
public static void main(String[] args) throws Throwable { try { throw new Throwable(); } catch (Exception e) { System.err.println("Caught in main()"); } }
}</source>