正则表达式在Java中的命名组

据我了解,该java.regex软件包不支持命名组(http://www.regular-expressions.info/named.html),所以有人可以将我指向具有此名称的第三方库吗?

我看过jregex,但是它的最新版本是2002年,它在java5下对我不起作用(承认我只是短暂地尝试过)。

回答:

每个名称只能具有一个命名组(你并不总是可以控制!),并且不能将它们用于正则表达式内递归。

注意:你可以在Perl和PCRE正则表达式中找到真正的正则表达式递归示例,如Regexp Power,PCRE规范和带有平衡括号的匹配字符串幻灯片中所述)

例:

String:

"TEST 123"

RegExp::

"(?<login>\\w+) (?<id>\\d+)"

Access

matcher.group(1) ==> TEST

matcher.group("login") ==> TEST

matcher.name(1) ==> login

Replace

matcher.replaceAll("aaaaa_$1_sssss_$2____") ==> aaaaa_TEST_sssss_123____

matcher.replaceAll("aaaaa_${login}_sssss_${id}____") ==> aaaaa_TEST_sssss_123____

public final class Pattern

implements java.io.Serializable

{

[...]

/**

* Parses a group and returns the head node of a set of nodes that process

* the group. Sometimes a double return system is used where the tail is

* returned in root.

*/

private Node group0() {

boolean capturingGroup = false;

Node head = null;

Node tail = null;

int save = flags;

root = null;

int ch = next();

if (ch == '?') {

ch = skip();

switch (ch) {

case '<': // (?<xxx) look behind or group name

ch = read();

int start = cursor;

[...]

// test forGroupName

int startChar = ch;

while(ASCII.isWord(ch) && ch != '>') ch=read();

if(ch == '>'){

// valid group name

int len = cursor-start;

int[] newtemp = new int[2*(len) + 2];

//System.arraycopy(temp, start, newtemp, 0, len);

StringBuilder name = new StringBuilder();

for(int i = start; i< cursor; i++){

name.append((char)temp[i-1]);

}

// create Named group

head = createGroup(false);

((GroupTail)root).name = name.toString();

capturingGroup = true;

tail = root;

head.next = expr(tail);

break;

}

以上是 正则表达式在Java中的命名组 的全部内容, 来源链接: utcz.com/qa/429709.html

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