JAVA 实现字符串倒序

递归实现字符串倒序

public class reverseString {
public static void main(String[] args) {
String str = "Hello World";
System.out.println(getReverseString(str));
System.out.println(getReverseStringByStack(str));
}

/**
* 通过JAVA 栈的方式实现字符串倒序
* @param str
* @return
*/
private static String getReverseStringByStack(String str) {
char[] stringArray = str.toCharArray();
Stack<Character> stack = new Stack<Character>();
for(int i = 0 ; i < stringArray.length ; i ++) {
stack.push(stringArray[i]);
}
String reserved="";
while (!stack.isEmpty()) {
reserved += stack.pop().toString();
}
return reserved;
}
/**
* 采用递归的方式
* @param str
* @return
*/
private static String getReverseString(String str) {
int length = str.length();
if (length <= 1) {
return str;
}
String a = str.substring(0, length / 2);
String b = str.substring(length / 2, length);
return getReverseString(b) + getReverseString(a);
}
}