java正则学习笔记三

/**
 * Greedy 数量词 
    X? X，一次或一次也没有 
    X* X，零次或多次 
    X+ X，一次或多次 
    X{n} X，恰好 n 次 
    X{n,} X，至少 n 次 
    X{n,m} X，至少 n 次，但是不超过 m 次 
 */
public static void main(String[] args) {
    //demo1();
    //demo2();
    //demo3();
    //demo4();
    //demo5();
    String regex = "[abc]{5,15}";
    System.out.println("abcba".matches(regex));
    System.out.println("abcbaabcabbabab".matches(regex));
    System.out.println("abcb".matches(regex));
    System.out.println("abcbaabaabcbaaba".matches(regex));
}

public static void demo5() {
    String regex = "[abc]{5,}";
    System.out.println("abcba".matches(regex));
    System.out.println("abcbaabcabbabab".matches(regex));
    System.out.println("abcb".matches(regex));
    System.out.println("abcbaaba".matches(regex));
}

public static void demo4() {
    String regex = "[abc]{5}";
    System.out.println("abcba".matches(regex));
    System.out.println("abcbaabcabbabab".matches(regex));
    System.out.println("abcb".matches(regex));
    System.out.println("abcbaaba".matches(regex));
}

public static void demo3() {
    String regex = "[abc]+";
    System.out.println("".matches(regex));
    System.out.println("a".matches(regex));
    System.out.println("aaaaabbbbccccc".matches(regex));
}

public static void demo2() {
    String regex = "[abc]*";
    System.out.println("".matches(regex));
    System.out.println("abc".matches(regex));
    System.out.println("a".matches(regex));
}

public static void demo1() {
    String regex = "[abc]?";
    System.out.println("a".matches(regex));
    System.out.println("b".matches(regex));
    System.out.println("c".matches(regex));
    System.out.println("d".matches(regex));
    System.out.println("".matches(regex));
}

}

java正则学习笔记三

原文：http://blog.51cto.com/357712148/2133865