string to string array conversion in java

Question

I have a string = "name"; I want to convert into a string array. How do I do it? Is there any java built in function? Manually I can do it but I'm searching for a java built in function.

I want an array where each character of the string will be a string. like char 'n' will be now string "n" stored in an array.

Answer 1

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.

Answer 2

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.

Answer 3

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.

Answer 4

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);
}

Answer 5

String data = "abc";
String[] arr = explode(data);

public String[] explode(String s) {
    String[] arr = new String[s.length];
    for(int i = 0; i < s.length; i++)
    {
        arr[i] = String.valueOf(s.charAt(i));
    }
    return arr;
}

Answer 6

In java 8, there is a method with which you can do this: toCharArray():

String k = "abcdef";
char[] x = k.toCharArray();

This results to the following array:

[a,b,c,d,e,f]

Answer 7

Simply use the .toCharArray() method in Java:

String k = "abc";
char[] alpha = k.toCharArray();

This should work just fine in Java 8.

Answer 8

String array = array of characters ?

Or do you have a string with multiple words each of which should be an array element ?

String[] array = yourString.split(wordSeparator);

Answer 9

Convert it to type Char?

http://www.javadb.com/convert-string-to-character-array

Answer 10

You could use string.chars().mapToObj(e -> new String(new char[] {e}));, though this is quite lengthy and only works with java 8. Here are a few more methods:

string.split(""); (Has an extra whitespace character at the beginning of the array if used before Java 8) string.split("|"); string.split("(?!^)"); Arrays.toString(string.toCharArray()).substring(1, string.length() * 3 + 1).split(", ");

The last one is just unnecessarily long, it's just for fun!

Answer 11

An additional method:

As was already mentioned, you could convert the original String "name" to a char array quite easily:

String originalString = "name";
char[] charArray = originalString.toCharArray();

To continue this train of thought, you could then convert the char array to a String array:

String[] stringArray = new String[charArray.length];
for (int i = 0; i < charArray.length; i++){
    stringArray[i] = String.valueOf(charArray[i]);
}

At this point, your stringArray will be filled with the original values from your original string "name". For example, now calling

System.out.println(stringArray[0]);

Will return the value "n" (as a String) in this case.

Answer 12

Splitting an empty string with String.split() returns a single element array containing an empty string. In most cases you'd probably prefer to get an empty array, or a null if you passed in a null, which is exactly what you get with org.apache.commons.lang3.StringUtils.split(str).

import org.apache.commons.lang3.StringUtils;

StringUtils.split(null)       => null
StringUtils.split("")         => []
StringUtils.split("abc def")  => ["abc", "def"]
StringUtils.split("abc  def") => ["abc", "def"]
StringUtils.split(" abc ")    => ["abc"]

Another option is google guava Splitter.split() and Splitter.splitToList() which return an iterator and a list correspondingly. Unlike the apache version Splitter will throw an NPE on null:

import com.google.common.base.Splitter;

Splitter SPLITTER = Splitter.on(',').trimResults().omitEmptyStrings();

SPLITTER.split("a,b,   c , , ,, ")     =>  [a, b, c]
SPLITTER.split("")                     =>  []
SPLITTER.split("  ")                   =>  []
SPLITTER.split(null)                   =>  NullPointerException

If you want a list rather than an iterator then use Splitter.splitToList().

Answer 13

here is have convert simple string to string array using split method.

String [] stringArray="My Name is ABC".split(" ");

Output

stringArray[0]="My";
stringArray[1]="Name";
stringArray[2]="is";
stringArray[3]="ABC";

Answer 14

/**
 * <pre>
 * MyUtils.splitString2SingleAlphaArray(null, "") = null
 * MyUtils.splitString2SingleAlphaArray("momdad", "") = [m,o,m,d,a,d]
 * </pre>
 * @param str  the String to parse, may be null
 * @return an array of parsed Strings, {@code null} if null String input
 */
public static String[] splitString2SingleAlphaArray(String s){
    if (s == null )
        return null;
    char[] c = s.toCharArray();
    String[] sArray = new String[c.length];
    for (int i = 0; i < c.length; i++) {
        sArray[i] = String.valueOf(c[i]);
    }
    return sArray;
}

Method String.split will generate empty 1st, you have to remove it from the array. It's boring.

Answer 15

Based on the title of this question, I came here wanting to convert a String into an array of substrings divided by some delimiter. I will add that answer here for others who may have the same question.

This makes an array of words by splitting the string at every space:

String str = "string to string array conversion in java";
String delimiter = " ";
String strArray[] = str.split(delimiter);

This creates the following array:

// [string, to, string, array, conversion, in, java]

Source

Tested in Java 8