optimization « Operation « Java Regex Q&A

1.	Development
2.	find
3.	group
4.	Match
5.	matcher
6.	number
7.	Operation
8.	parse
9.	Pattern
10.	replace
11.	validation
12.	word

Java Regex Q&A » Operation » optimization

1. Regex optimisation - escaping ampersands in java stackoverflow.com

I need to replace all & in a String that isnt part of a HTML entity. So that the String "This & entites > & <" will return "This & entites ...

2. Regex optimization question stackoverflow.com

As a personal learning exercise, I wrote this regex to split a unary string into parts whose length is increasing powers of two (see also on ideone.com):

...

3. Regex speed in Java stackoverflow.com

Some example wallclock times for a large number of strings:

.split("[^a-zA-Z]"); // .44 seconds
.split("[^a-zA-Z]+"); // .47 seconds
.split("\\b+"); // 2 seconds

Any explanations for the dramatic increase? I can imagine the [^a-zA-Z] pattern being ...

4. Java regular expression optimization tips stackoverflow.com

I am new to Java Regular expression. We are using a pattern for matching a string. We are using this for validating a text field and it meets our requirements. But ...

5. Optimizing several RegEx in Java Code stackoverflow.com

The below mentioned RegEx perform very poorly on a very large string or more than 2000 Lines. Basically the Java String is composed of PL/SQL script. 1- Replace each occurrence of ...

6. Java regular expression optimization - help needed coderanch.com

Hi All, I am new to Java Regular expression. We are using a pattern for matching a string. We are using this for validating a text field and it meets our requirements. But there is a performance issue in the matching. pattern :([a-zA-Z0-9]+[ ]?(([_\-][a-zA-Z0-9 ])*)?[_\-]?)+ 1. Input text should start with a-zA-Z0-9. 2. Space(single) is allowed between words 3. "_" and ...

7. Regex Optimization forums.oracle.com

Hi, The way your going about writing and testing your RegEx seems a 'small' bit convoluted, especially for the task you've outlined. Really the RegEx should be quite short. The following link gives a good example of a RegEx tester and all the info you need to write more efficient RegEx's! [http://java.sun.com/docs/books/tutorial/essential/regex/index.html] Good luck.