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thru.
Asked: 2020-10-01 07:45:30 +0800 CST 2020-10-01 07:45:30 +0800 CST

Static methods definition? JAVA

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I have a problem defining a static method in a class, see if you can help me:

public boolean checkcmd(String in, String cmd, String ... arg)
{
	...
	check.a(); // esta linea
	...
}
class check
{
	static void a()
	{
		...
	}
}

The error I get is "Unreachable code", on the marked line.

Thank you very much!

java

1 Answers

  1. Best Answer

    The compiler detects that the method, at some point, is going to terminate somehow or that there is no way to continue execution, so code written after that end point will not be executed . This generates the "Unreachable code".

    Examples:

    1. Deliberately throw an exception:

      public void x() {
    throw new UnsupportedOperationException("no ejecutar");
    //el código después de este throws no se puede ejecutar
    System.out.println("x");
}

    2. Return a value, or simply return if it is a method void:

      public void x() {
    return;
    //el código después de este return no se puede ejecutar
    System.out.println("x");
}

    3. Have an infinite loop:

      public void x() {
    while (true) {
        /* funcionalidad */
    }
    //el código después de un bucle infinito
    System.out.println("x");
}

    There are cases where it is a bit more difficult to detect (but not impossible). Example:

    public int duplicar(int a) {
    if (a >= 0) {
        return a * 2;
    } else {
        throw new IllegalArgumentException("solo para numeros positivos");
    }
    //la sentencia de abajo genera Unreachable code
    System.out.println("Código inalcanzable!");
}

    That said, we need your full code to detect the unreachable code.

    That the method called inside your instance method is a static method is not associated with the problem .

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