Java将字符串反转的7种方法

//方法1 递归方法

public static String reverse1(String s) {

  int length = s.length();

  if(length <= 1){

    return s;

    }

  String left = s.substring(0, length / 2);

  String right = s.substring(length / 2, length);

  return reverse1(right) + reverse1(left);

}

//方法2 通过 charAt(int index)返回char值进行字符串拼接

public static String reverse2(String s) {

  int length = s.length();

  String reverse = "";

  for(int i = 0; i < length; i++)

  reverse = s.charAt(i) + reverse;

  return reverse;

}

//方法3 把字符串转换成字符数组倒叙拼接然后返回值

public static String reverse3(String s) {

  char[] array = s.toCharArray();

  String reverse = "";

  for(int i = array.length - 1; i >= 0; i--)

  reverse += array[i];

  return reverse;

}

//方法4 调用StringBuffer中的reverse方法

public static String reverse4(String s) {

  return new StringBuffer(s).reverse().toString();

}

//方法5 把字符串转换成字符数组首位对调位置

public static String reverse5(String orig) {

  char[] s = orig.toCharArray();

  intn = s.length - 1;

  int halfLength = n / 2;

  for(int i = 0; i <= halfLength; i++) {

  chartemp = s[i];

  s[i] = s[n - i];

  s[n - i] = temp;

  }

  return new String(s);

}

//方法6

public static String reverse6(String s) {

  char[] str = s.toCharArray();

  int begin = 0;

  int end = s.length() - 1; 

  while(begin < end) {

  str[begin] = (char) (str[begin] ^ str[end]);

  str[end] = (char) (str[begin] ^ str[end]);

  str[begin] = (char) (str[end] ^ str[begin]);

  begin++;

  end--;  }

return new String(str);

}

//方法7

import java.util.Stack;

public class StringReverse {   

public static String reverse7(String s) {

  char[] str = s.toCharArray();

  Stack<Character> stack = new Stack<Character>();

  for (int i = 0; i < str.length; i++)

  stack.push(str[i]);

  String reversed = "";

  for (int i = 0; i < str.length; i++)

  reversed += stack.pop();

  return reversed;

}

}