string to string array conversion in java

Question

To start you off on your assignment, String.split splits strings on a regular expression and this expression may be an empty string:

String[] ary = "abc".split("");

Yields the array:

(java.lang.String[]) [, a, b, c]

Getting rid of the empty 1st entry is left as an exercise for the reader :-)

Note: In Java 8, the empty first element is no longer included.

String strName = "name";
String[] strArray = new String[] {strName};
System.out.println(strArray[0]); //prints "name"

The second line allocates a String array with the length of 1. Note that you don't need to specify a length yourself, such as:

String[] strArray = new String[1];

instead, the length is determined by the number of elements in the initalizer. Using

String[] strArray = new String[] {strName, "name1", "name2"};

creates an array with a length of 3.

Assuming you really want an array of single-character strings (not a char[] or Character[])

1. Using a regex:

public static String[] singleChars(String s) {
    return s.split("(?!^)");
}

The zero width negative lookahead prevents the pattern matching at the start of the input, so you don't get a leading empty string.

2. Using Guava:

import java.util.List;

import org.apache.commons.lang.ArrayUtils;

import com.google.common.base.Functions;
import com.google.common.collect.Lists;
import com.google.common.primitives.Chars;

// ...

public static String[] singleChars(String s) {
    return
        Lists.transform(Chars.asList(s.toCharArray()),
                        Functions.toStringFunction())
             .toArray(ArrayUtils.EMPTY_STRING_ARRAY);
}

I guess there is simply no need for it, as it won't get more simple than

String[] array = {"name"};

Of course if you insist, you could write:

static String[] convert(String... array) {
   return array;
}

String[] array = convert("name","age","hobby"); 

[Edit] If you want single-letter Strings, you can use:

String[] s = "name".split("");

Unfortunately s[0] will be empty, but after this the letters n,a,m,e will follow. If this is a problem, you can use e.g. System.arrayCopy in order to get rid of the first array entry.