Re: unable to understand some code

From:

Jeff Higgins <jeff@invalid.invalid>

Newsgroups:

comp.lang.java.programmer

Date:

Wed, 25 Mar 2015 08:11:47 -0400

Message-ID:

<meu8mo$abv$1@dont-email.me>

On 03/25/2015 02:56 AM, Vish wrote:

public class Test
{
     private final static Class<?>[] TEST_CLASSES = new Class[]{};
     private static final String DEFAULT_OS = "window";
     private static final String DEFAULT_BROWSER = "firefox";

     public static void main(String[] args)
     {
         if (args.length > 0) {
             for (int i = 0; i < args.length && args[i].split("=").length == 2; i++) {
                 String key = args[i].split("=")[0];
                 String value = args[i].split("=")[1];
                 System.setProperty(key, value);
             }
         }

         System.out.println("window: " + System.getProperty("window", DEFAULT_OS));

         List<String> testSuites = new ArrayList<String>();

        ----
        some other code
        ----
    }

    I am not able to understand below things from above code, Please help me to understand the below

    1. Mentioned inside the for loop, (i < args.length && args[i].split("=").length == 2), what does mean "args[i].split("=").length == 2"

    2. String key = args[i].split("=")[0];
        String value = args[i].split("=")[1];
in 2nd point seems like array 1st and 2nd index for [0] and [1] but confusing

      What does mean args[i].split("=")[0]; and args[i].split("=")[1]; I am confused with [0] and [1] written in the end

Look in the Javadoc for the documentation for java.lang.String
split(String regex) method.

Arrays have a public int field (length) which holds the count of the
array's entries.

== is the Java equality operator.

Java array indexes are zero based.

package scratch;

public class Test {

   public static void main(String[] args) {

     System.out.println(args.length + " : number of Strings contained by
args\n");

     for(String arg : args) {
       System.out.println(arg);
       String[] temp;
       temp = arg.split("=");
       int count = temp.length;
       System.out.println(count + " : number of Strings contained by temp");
       if(temp.length == 2) {
         System.out.println("String array temp contains two entries");
       }
       else {
         System.out.println("String array temp does not contain two
entries");
       }
       for(String s : temp) {
         System.out.println(s);
       }
       System.out.println();
     }

   }

}