String to Char Conversion in Java

Sometimes we have to convert String to the character array in java programs or convert a string to char from specific index.

String to char Java

String class has three methods related to char. Let’s look at them before we look at a java program to convert string to char array.

• char[] toCharArray(): This method converts string to character array. The char array size is same as the length of the string.
• char charAt(int index): This method returns character at specific index of string. This method throws StringIndexOutOfBoundsException if the index argument value is negative or greater than the length of the string.
• getChars(int srcBegin, int srcEnd, char dst[], int dstBegin): This is a very useful method when you want to convert part of string to character array. First two parameters define the start and end index of the string; the last character to be copied is at index srcEnd-1. The characters are copied into the char array starting at index dstBegin and ending at dstBegin + (srcEnd-srcBegin) - 1.

Let’s look at a simple string to char array java program example.

package com.journaldev.string;

public class StringToCharJava {

    public static void main(String[] args) {
        String str = "journaldev";
        
        //string to char array
        char[] chars = str.toCharArray();
        System.out.println(chars.length);
        
        //char at specific index
        char c = str.charAt(2);
        System.out.println(c);
        
        //Copy string characters to char array
        char[] chars1 = new char[7];
        str.getChars(0, 7, chars1, 0);
        System.out.println(chars1);
        
    }

}

Consclusion

In above program, toCharArray and charAt usage is very simple and clear. In getChars example, first 7 characters of str will be copied to chars1 starting from its index 0. That’s all for converting string into char java program.