1 package FileDemo; 2  3 import java.io.IOException; 4  5 public class CutStringTest { 6  7     /** 8      * @param args 9      * @throws IOException10      */11     public static void main(String[] args) throws IOException {12 13         String str = "ab你好cd谢谢";14         /*byte buf[]=str.getBytes("GBK");15         for(byte ch:buf){16             System.out.println(Integer.toBinaryString(ch));17         }*/18         int len = str.getBytes("gbk").length;19         for (int x = 0; x < len; x++) {20             System.out.println("截取" + (x + 1) + "字节结果时："21                     + cutStringByByte(str, x + 1));22         }23         String str1 = "ab你好cd杮";24         int len1 = str.getBytes("gbk").length;25         for (int x = 0; x < len1; x++) {26             System.out.println("截取" + (x + 1) + "字节结果时："27                     + cutStringByU8(str1, x + 1));28         }29     }30 31     // 使用UTF-8编码表进行截取字符串，一个汉字对应三个负数，一个英文字符对应一个正数32     private static String cutStringByU8(String str, int len) throws IOException {33 34         byte[] buf = str.getBytes("utf-8");35         int count = 0;36         for (int x = len - 1; x >= 0; x--) {37             if (buf[x] < 0) {38                 count++;39             } else {40                 break;41             }42         }43         if (count % 3 == 0) {44             return new String(buf, 0, len, "utf-8");45         } else if (count % 3 == 1) {46             return new String(buf, 0, len - 1, "utf-8");47         } else {48             return new String(buf, 0, len - 2, "utf-8");49         }50     }51 52     // 使用GBK编码表进行字符串的截取，一个英文字符对应码表一个正数，一个汉字对应两个负数53     public static String cutStringByByte(String str, int len)54             throws IOException {55         byte[] buf = str.getBytes("gbk");56         int count = 0;57         for (int x = len - 1; x >= 0; x--) {58             if (buf[x] < 0) {59                 count++;60             } else {61                 break;62             }63         }64         if (count % 2 == 0) {65             return new String(buf, 0, len, "gbk");66         } else {67             return new String(buf, 0, len - 1, "gbk");68         }69     }70 71 }