输出：

Reverse of the given string is : sediuG avaJ

8. 使用 Byte 数组

package net.javaguides.corejava.string;
/**
 * 
 * @author Ramesh Fadatare
 *
 */
public class ReverseStringUsingByteArray {
    // Function to reverse a string in Java using byte array
    public static String reverse(String str) {
        // return if string is null or empty
        if (str == null || str.equals(""))
            return str;
        // convert string into bytes
        byte[] bytes = str.getBytes();
        // start from the two end points l and h of the given string
        // and increment l & decrement h at each iteration of the loop
        // until two end-points intersect (l >= h)
        for (int l = 0, h = str.length() - 1; l < h; l++, h--) {
            // Swap values at l and h
            byte temp = bytes[l];
            bytes[l] = bytes[h];
            bytes[h] = temp;
        }
        // convert byte array back into the string
        return new String(bytes);
    }
    public static void main(String[] args) {
        String str = "Java Guides";
        // String is immutable
        str = reverse(str);
        System.out.println("Reverse of the given string is : " + str);
    }
}

输出：

Reverse of the given string is : sediuG avaJ

9. 使用 substring() 方法

package net.javaguides.corejava.string;
/**
 * 
 * @author Ramesh Fadatare
 *
 */
public class UsingSubStringFunction {
    // Function to reverse a string in Java using recursion
    private static String reverse(String str) {
        // base case: if string is null or empty
        if (str == null || str.equals(""))
            return str;
        // last character + recurse for remaining string
        return str.charAt(str.length() - 1) + reverse(str.substring(0, str.length() - 1));
    }
    public static void main(String[] args) {
        String str = "javaguides";
        // string is immutable
        str = reverse(str);
        System.out.println("Reverse of the given string is : " + str);
    }
}

输出：

Reverse of the given string is : sediugavaj

10. 使用递归

package net.javaguides.corejava.string;
/**
 * 
 * @author Ramesh Fadatare
 *
 */
public class UsingRecursion {
    static int i = 0;
    // Recursive function to reverse a string in Java using static variable
    private static void reverse(char[] str, int k) {
        // if we have reached the end of the string
        if (k == str.length)
            return;
        // recurse for next character
        reverse(str, k + 1);
        if (i <= k) {
            char temp = str[k];
            str[k] = str[i];
            str[i++] = temp;
        }
    }
    public static String reverse(String str) {
        // base case: if string is null or empty
        if (str == null || str.equals(""))
            return str;
        // convert string into a character array
        char[] A = str.toCharArray();
        // reverse character array
        reverse(A, 0);
        // convert character array into the string
        return String.copyValueOf(A);
    }
    public static void main(String[] args) {
        String str = "Java Guides";
        // string is immutable
        str = reverse(str);
        System.out.println("Reverse of the given string is : " + str);
    }
}

输出：

Reverse of the given string is : sediuG avaJ

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