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廖雪峰Java9正则表达式-1正则表达式入门-2正则表达式匹配规则
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正则表达式的匹配规则：
- 从左到右按规则匹配
| 匹配规则及示例 | 可以匹配 | 不能匹配 |
|---|---|---|
| "abc" | "abc" | 不能匹配："ab", "Abc", "abcd" |
| 特殊字符需要转义，如"a&c"，注意Java的字符串需要再加一个转义符 | "a&c" | "ab", "abc", "a&cd" |
| 非ascii字符用"\u####"表示一个unicode字符，如"a\u548cc" | "a和c" | "a与c","a&c","abc" |
| . 可以匹配任意一个字符："a.c" | "abc", "a&c" | "ac", "abbc" |
| \d 可以匹配一个数字："00\d" | "007", "008" | "00A", "0077" |
| \D可以匹配一个非数字："00\D" | "00A", "00#" | "001" |
| \w可以匹配一个字母、数字或下划线："java\w" | "javac", "java8", "java_", | "java#", "java " |
| \s可以匹配一个空白字符："A\sB" | "A B" "A B"，tab键也算空白字符 | "AB" "A B" |
| \W可以匹配一个非字母、数字或下划线："java\W" | "java!", "java " | "javac", "java8", "java_" |
| \S可以匹配一个非空白字符："A\SB" | "A&B", "ABB" | "A B","A B"tab键也算空白字符 |
| 修饰符 可以匹配 前的任意个字符："A\d*"，先匹配字母A，再匹配任意多个数字 | "A", "A1", "A007" | "AB" |
| 修饰符+可以匹配+前的至少一个字符："A\d+"，先匹配字母A，再匹配至少1个数字 | "A1","A007" | "A", "AB" |
| 修饰符?可以匹配0个或1个字符："A\d?"，先匹配字母A，再匹配0个或1个数字 | "A","A1" | "A12","AB" |
| 修饰符{n}可以匹配n个字符："\d{6}" | "123456", "999999" | "12345","1234567", "12345A" |
| 修饰符{m,n}，可以匹配m-n个字符"\d{3,5}" | "123", "12345" | "12","12345", "123A5" |
| 修饰符{n,}可以匹配至少n个字符:"\d{3,}" | "123", "1234", "123456789" | "12","123A" |
| ^和\(匹配开头和结尾："^A\d{3}\)" | "A001", "A999" | "B001", "A0001" |
| [...]可以匹配范围内的字符: "[abc]1" | "a1", "b1", "c1" | "ab1", "x1" |
| "[a-f]1" | "a1", "b1", "f1" | "g1", "ab1" |
| "[a-f0-9]{6}" | "1a2b3c", "ffffff", "ff0102" | "abc12", "A0000F" |
| [^...] 在中括号内表示非，"[ 0-9]{6} 6位非数字字符串 | "abcdef", "$$$$$$", "A-B-C-" | "1a2b3c", "A0000F" |
| AB|CD可以匹配AB或CD；如"java|php" | "java", "php" | "C++", "jphp" |
| "learn\s(java|php)" | "learn java", "learn php" | "learn C++", "learn python" |
| "learn\sjava|php" | "learn java", "php" | "learn java", "learn php" |
package com.testRegex;
public class Telephone {
public static Boolean invaildTel(String s) {
return s.matches("\\d{3,4}\\-\\d{6,8}");
}
}
package com.testRegex;
import static org.junit.Assert.*;
import org.junit.Test;
public class TelephoneTest {
@Test
public void testInvaildTel() {
assertTrue(Telephone.invaildTel("010-123456"));
assertTrue(Telephone.invaildTel("010-12345678"));
assertTrue(Telephone.invaildTel("0123-123456"));
assertTrue(Telephone.invaildTel("0123-12345678"));
assertTrue(Telephone.invaildTel("123-123456"));
assertTrue(Telephone.invaildTel("123-12345678"));
assertFalse(Telephone.invaildTel("010#123456"));
assertFalse(Telephone.invaildTel("010X12345678"));
assertFalse(Telephone.invaildTel("01-12345678"));
assertFalse(Telephone.invaildTel("01234-12345678"));
assertFalse(Telephone.invaildTel("01A-12345678"));
assertFalse(Telephone.invaildTel("0123-12345"));
assertFalse(Telephone.invaildTel("0123-12345X"));
assertFalse(Telephone.invaildTel("0123-123456789"));
assertFalse(Telephone.invaildTel("0123-12345678X"));
}
}
匹配QQ号，非0开头的5到11位数字字符串
package com.testList;
public class QQ {
public static Boolean isVaildQQ(String s){
return s.matches("^[1-9]\\d{4,10}$");
}
}
package com.testList;
import org.junit.Test;
import static org.junit.Assert.*;
public class QQTest {
@Test
public void isVaildQQ() {
assertTrue(QQ.isVaildQQ("10000"));
assertTrue(QQ.isVaildQQ("99999"));
assertTrue(QQ.isVaildQQ("1234567890"));
assertTrue(QQ.isVaildQQ("9999999999"));
assertFalse(QQ.isVaildQQ("00001"));
assertFalse(QQ.isVaildQQ("099999"));
}
}
电话号码优化，区号必须以0开头，电话号码不能以0开头
package com.testList;
public class Phone{
public static boolean isVaildPhone(String s){
return s.matches("^0\\d{2,3}(\\-|\\s)[1-9]\\d{6,7}$");
}
}
package com.testList;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import static org.junit.Assert.*;
public class PhoneTest {
@Test
public void testIsVaildPhone(){
assertTrue(Phone.isVaildPhone("012-12345678"));
assertTrue(Phone.isVaildPhone("012 12345678"));
assertTrue(Phone.isVaildPhone("0123 1234567"));
assertTrue(Phone.isVaildPhone("0123-1234567"));
assertTrue(Phone.isVaildPhone("012 12345678"));
assertFalse(Phone.isVaildPhone("123-12345678"));
assertFalse(Phone.isVaildPhone("123-0123456"));
assertFalse(Phone.isVaildPhone("023-0123456"));
assertFalse(Phone.isVaildPhone("023-01234567"));
}
}
