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Regex for IP and string

Im using this regex online test site.
Here is the regex im using:
\{"ip":"(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$","iphone":"admin/ios","dev":\{"action":"CUS","from":"REG","CUSA":"ADVERT"\}\}
And im trying to match it to:
{"ip":"192.168.50.5","iphone":"admin/ios","dev":{"action":"CUS","from":"REG","CUSA":"ADVERT"}}
When i run the test, it doesn't match, I need it to match on the site above for validation reasons.

A different perspective: it seems that it is already pretty hard to come up with a regex that initially works for you. What does this tell you about how hard will it be in the future to maintain this regex; and maybe extend it?!
What I am saying is: regexes are a good tool; but sometimes overrated. This looks like a string in JSON format. Wouldn't it be better to just take it as that, and use a garden-variety JSON parser instead of trying to build your own regex?
You see, what will be more robust over time - your self baked regex; or some standard library that millions of people are using?
One place to read about JSON parsers would be this question here.

This will be enough for your context.
"ip":"(\d+).(\d+).(\d+).(\d+)"
Edit:
Regex is not for structured data processing, most of the time you need a solution that just works. When sample data changed and doesn't match anymore, you update the regex string to match it again.
Since you want to get four numbers inside a quote pair after a key called "ip", this regex will definitely do it.
If you want something else, please provide more context. Thanks!

How to search for a string and append to each occurance in Java

Currently I am working on a project and I am trying to see which String method would be most appropriate to use or how to approach this. I am trying to prepend a string to each occurrence of this specific string. For example, I am extracting HTML and for each /img/image1.png I find I want to append a url to it.
However, there are images that are already like that for example www.anylink.com/img/image2.png which do not need appending but are in the string in which I pulled. I looked at replaceAll() method but not sure if this allows for appending in replacement and also not sure if I need regex to search for instances where only /img/ exists(no url) and not the full url since only local hosted images I want to append to. I am looking for some suggestions as I am not sure how to begin this code after research.
Thank you.

I think that the method replaceAll() in String is enough for what you need.
You just need to write the correct regular expression.
If you write some examples, I can suggest the regex.
For example something like:
System.out.println("<div><img src=\"/test/this.png\" /></div>".replaceAll("src=\"/(.*)\"", "src=\"www.google.com$1\""));

Java Regex for Finding a Pattern and Getting Value in It?

I am working on a plugin. I will parse HTML files. I have a naming convention like that:
<!--$include="a.html" -->
or
<!--$include="a.html"-->
is similar
According to this pattern(similar to server side includes) I want to search an HTML file.
Question is that:
Find that pattern and get value (a.html at my example, it is variable)
It should be like:
while(!notFinishedWholeFile){
fileName = findPatternFunc(htmlFile)
replaceFunc(fileName,something)
}
PS: Using regex at Java or implementing it different(as like using .indexOf()) I don't know which one is better. If regex is good at this situation by performence I want to use it.
Any ideas?

You mean like this?
<!--\$include=\"(?<htmlName>[a-z-_]*).html\"\s?-->

Read a file into a string then
str = str.replaceAll("(?<=<!--\\$include=\")[^\"]+(?=\" ?-->)", something);
will replace the filenames with the string something, then the string can be written back to the file.
(Note: this replaces any text inside the double quotes, not just valid filenames.)
If you want only want to replace filenames with the html extension, swap the [^\"]+ for [^.]+.html.
Using regex for this task is fine performance wise, but see e.g.
How to use regular expressions to parse HTML in Java? and Java Regex performance etc.

I have used that pattern:
"<!--\\$include=\"(.+)(.)(html|htm)\"-->"

Java String quote delimiter

Is there any way in Java to use a special delimiter at the start and the end of a String to avoid having to backslash all of the quotes within that String?
i.e. not have to do this:
String s = "Quote marks like this \" are just the best, here are a few more \" \" \""

No, there is no such option. Sorry.

No - there's nothing like C#'s verbatim string literals or Groovy's slashy strings, for example.
On the other hand, it's the kind of feature which may be included in the future. It's not like it would require any fundamental changes in the type system. I'd be hugely surprised for it to make it into Java 7 this late in the day though, and I haven't seen any suggestions that it'll be in Java 8... so you're in for a long wait :(

The only way to achive this is to put your strings in some other file and read it from Java. For instance a resource bundle.

Its not possible as of now, May be NOT in future also.
if you can give us what and why you are loookng for this kind of feature we can defnitely Suggest some more alternatives

Need a little help on this regular expression

I have a Java string which looks like this, it is actually an XML tag:
"article-idref="527710" group="no" height="267" href="pc011018.pct" id="pc011018" idref="169419" print-rights="yes" product="wborc" rights="licensed" type="photo" width="322" "
Now I want to remove the article-idref="52770" segment by using regular expression, I came up with the following one:
trimedString.replaceAll("\\article-idref=.*?\"","");
but it doesn't seem to work, could anybody give me an idea on where I got wrong in my regular expression? I need this to be represented as a String in my Java class, so probably HTMLParser won't help me a lot here.
Thanks in advance!

Try this:
trimedString.replaceAll("article-idref=\"[^\"]*\" *","");

I corrected the regular expression by adding quotes and a word boundary (to prevent false matches). Also, in case you didn't, remember to reassign to your string after the replacement:
trimmedString = trimmedString.replaceAll("\\barticle-idref=\".*?\"", "");
See it working at ideone.
Also since this is from an XML document it might be better to use an XML parser to extract the correct attributes instead of a regular expression. This is because XML is quite a complex data format to parse correctly. The example in your question is simple enough. However a regular expression could break on a more complex case, such as a document that includes XML comments. This could be an issue if you are reading data from an untrusted source.

if you are sure the article-idref is allways at the beginning try this:
// removes everything from the beginning to the first whitespace
trimedString = trimedString.replaceFirst("^\\s","");
Be sure to assign the result to trimedString again, since replace does not midify the string itself but returns another string.