charTest

/*

    modemnoise.blogspot.com
    Simple program to print out the Printable characters in ASCII.

    Print int value, character and hex value
    Test if Java identifier and legal start of
    java identifier

*/
class chartest {

    public static void main(String[] args) {

        System.out.println();
        System.out.println("Int\tChar\tHex\tJava\tJavStart");
        System.out.println("----------------------------------------");

        // Loop through the printable charaters of the ASCII table
        // Printable character go from 33 == '!' to 126 == '~'
        for (int i = 33; i < 127; i++){

            // Example of some formatting argumentss and flags
            // 1$ references 1st attribute 2$ the second etc
            // 04d formats an integral value 4 chars wide with 0s padding to left
            // 04X formats a hex value in uppercase 4 chars wide with 0s padding to left
            // 04x would do the same as above but with lowercase hex
            // Note the 0x in the example below is printed data not reference to attribute
            System.out.printf("%1$04d\t%1$c\t0x%1$04X\t", i);

            // Outer if using the Character wrapper class to test
            // if character can be used in a Java identifier
            if (Character.isJavaIdentifierPart(i)){

                System.out.print("y\t");

                // Nested if using the Character wrapper class to test
                // if character can be used to start a Java identifier
                // Nested as no point testing if not a legal character
                // for Java identifier.
                if (Character.isJavaIdentifierStart(i)){
                    System.out.print("y");
                } //inner if

            } //outer if

            // new line after each iteratiion of loop
            System.out.println();
        }//for

    }   //main
}//class