Java/strings/ReverseString.java at master · debugmm/Java · GitHub

41 lines (35 loc) · 959 Bytes

package strings;

/** Reverse String using different version */

public class ReverseString {

public static void main(String[] args) {

assert reverse("abc123").equals("321cba");

assert reverse2("abc123").equals("321cba");

}

/**

* easiest way to reverses the string str and returns it

* @param str string to be reversed

* @return reversed string

public static String reverse(String str) {

return new StringBuilder(str).reverse().toString();

}

/**

* second way to reverses the string str and returns it

* @param str string to be reversed

* @return reversed string

public static String reverse2(String str) {

if (str == null || str.isEmpty()) {

return str;

}

char[] value = str.toCharArray();

for (int i = 0, j = str.length() - 1; i < j; i++, j--) {

char temp = value[i];

value[i] = value[j];

value[j] = temp;

}

return new String(value);

}

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