典型字符串处理代码

package com.arithmetic;public class StringApi {// 判断字符串是否是一条回文public static boolean isPalindrome(String s) {int N = s.length();for (int i = 0; i < N/2; i++) {if (s.charAt(i) != s.charAt(N-1-i)) {return false;}}return true;}// 提取文件名和扩展名public static void getFileName(String fileName) {int dot = fileName.indexOf(".");String baseName = fileName.substring(0,dot);String extendName = fileName.substring(dot + 1, fileName.length());System.out.println("文件名：" + baseName);System.out.println("扩展名：" + extendName);}// 检查一个字符串数组的元素是否按照字母表元素排序public static boolean isSorted(String[] a) {for (int i = 1; i < a.length; i++) {if (a[i-1].compareTo(a[i]) > 0) {return false;}}return true;}public static void main(String[] args) {String a = "ABCDDCBA";System.out.println(isPalindrome(a));String fileName = "软件回文测试系统文档.docx";getFileName(fileName);String[] arr = {"ab","abce","abc","ddd"};boolean sorted = isSorted(arr);System.out.println(sorted);}}