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parsing a string using string tokenizer twice

I am getting input string as below from some procedure
service:jmx:t3://10.20.30.40:9031/jndi/weblogic.management.mbeanservers.runtime
I want to parse it in java and get out
t3
10.20.30.40
9031
into separate strings
I think I can use string tokenizer but I have to tokenize 2 times ?Any better way to handle this?

Use the JMXServiceUrl class. It will parse the URL for you. No need to battle with regex or String splits.
String url = "service:jmx:t3://10.20.30.40:9031/jndi/weblogic.management.mbeanservers.runtime";
JMXServiceURL jmxServiceURL = new JMXServiceURL(url);
System.out.println(jmxServiceURL.getHost());
System.out.println(jmxServiceURL.getPort());
System.out.println(jmxServiceURL.getProtocol());
Prints
10.20.30.40
9031
t3

If it's only a somehow composed String and you can ignorie performance, I would prefer a readable solution (more than regex ;-)) like this:
int pos_1 = input.indexOf("//");
String s1 = input.substring(0, pos_1);
String input_2 = input.substring(pos_1 + 2);
int pos_2 = input_2.indexOf(":");
String s2 = input_2.substring(0, pos_2);
...

Regex is a good approach. You should find the pattern for your string and group with parenthesis what you want. Maybe this could be enough for you:
service\\:jmx\\:(?<groupName01>[a-z0-9]+)\\://(?<groupName02>[0-9\\.]+)\\:(?<groupName03>[o-9]+)
See Java Regex
If you use java earlier from 7, do not use ?<groupName> in the pattern. It will be grouped by number.

Do a simple string split
String s = "service:jmx:t3://10.20.30.40:9031/jndi/weblogic.management.mbeanservers.runtime";
String tokens[] = s.split("[:/]");
System.out.println(tokens[2]);
System.out.println(tokens[5]);
System.out.println(tokens[6]);

Extract text from string Java

With this string "ADACADABRA". how to extract "CADA" From string "ADACADABRA" in java.
and also how to extract the id between "/" and "?" from the link below.
http://www.youtube-nocookie.com/embed/zaaU9lJ34c5?rel=0
output should be: zaaU9lJ34c5
but should use "/" and "?" in the process.

and also how to extract the id between "/" and "?" from the link below.
http://www.youtube-nocookie.com/embed/zaaU9lJ34c5?rel=0
output should be: zaaU9lJ34c5
Should be :
String url = "http://www.youtube-nocookie.com/embed/zaaU9lJ34c5?rel=0";
String str = url.substring(url.lastIndexOf("/") + 1, url.indexOf("?"));

String s = "ADACADABRA";
String s2 = s.substring(3,7);
Here 3 specifies the beginning index, and 7 specifies the stopping point.
The string returned contains all the characters from the beginning index, up to, but not including, the ending index.

I'm not entirely sure what you mean by extract, so I've provided the code to remove it from the String, I'm not certain if this is what you want.
public static void main (String args[]){
String string = "ADACADABRA";
string = string.replace("CADA", "");
System.out.println(string);
}

This is untested but something like this may help for the youtube part:
String youtubeUrl = "http://www.youtube-nocookie.com/embed/zaaU9lJ34c5?rel=0";
String[] urlParts = youtubeUrl.split("/");
String videoId = urlParts[urlParts.length - 1];
videoId = videoId.substring(0, videoId.indexOf("?"));
Extracting CADA from the string makes no sense. You will need to specify how you have determined that CADA is the string to extract.
E.g. is it because it is the middle 4 characters? Is it because you are stripping off 3 characters each side? Are you just looking for the String "CADA"? Is it characters 3,7 of the String? Is it the first 4 of the last 7 characters of a String? Is it because it contains 2 vowels and 2 consanants? I could go on..

String regex = "CADA";
Pattern p = Pattern.compile(regex, Pattern.MULTILINE);
Matcher m = p.matcher(originalText);
while (m.find()) {
String outputThis = m.group(1);
}
Use this tool http://www.regexplanet.com/advanced/java/index.html

Probably, you don't take in account the fact of java.lang.String immutability. That's why you need to assign the result of substringing to a new variable.

How to extract a url from a string in Java?

I have a string containing a short-code which looks like the one below:
some text...
[video url="http://www.example.com/path/to/my/video.ext"]
...some more text...
I want to be able to first check if the string contains that short-code and second extract the URL from it in Java (specifically Android).

use this regex for checking and grabbing url:
\[\w+\s+url="(?<urllink>)[^"]*"\s*]
and get gorup named urllink

try as:
String str = "[video url=\"http://www.example.com/path/to/my/video.ext\"]";
if (str.contains("url=\""))
{
int indexoff = str.indexOf("url=\"");
int indexofff = str.indexOf("\"]");
String strurl = str.substring(indexoff, indexofff - indexoff);
strurl = strurl.Replace("url=\"", ""); //get url string here
}

Android provides several function for this purpose. SOme of this are:
http://hc.apache.org/httpcomponents-client-ga/httpclient/apidocs/org/apache/http/client/utils/URLEncodedUtils.html
http://developer.android.com/reference/org/apache/http/client/utils/URLEncodedUtils.html

String url = "whatever"
Boolean myBool = url.contains("ate");
String contains. Not sure what extract url means, but the string class has lots of useful functions.

A powerful and maintainable manner it to Java URL.class, then, you can mix with Regex

Need to Trim Java String

I need help in trimming a string url.
Let's say the String is http://myurl.com/users/232222232/pageid
What i would like returned would be /232222232/pageid
Now the 'myurl.com' can change but the /users/ will always be the same.

I suggest you use substring and indexOf("/users/").
String url = "http://myurl.com/users/232222232/pageid";
String lastPart = url.substring(url.indexOf("/users/") + 6);
System.out.println(lastPart); // prints "/232222232/pageid"
A slightly more sophisticated variant would be to let the URL class parse the url for you:
URL url = new URL("http://myurl.com/users/232222232/pageid");
String lastPart = url.getPath().substring(6);
System.out.println(lastPart); // prints "/232222232/pageid"
And, a third approach, using regular expressions:
String url = "http://myurl.com/users/232222232/pageid";
String lastPart = url.replaceAll(".*/users", "");
System.out.println(lastPart); // prints "/232222232/pageid"

string.replaceAll(".*/users(/.*/.*)", "$1");

String rest = url.substring(url.indexOf("/users/") + 6);

You can use split(String regex,int limit) which will split the string around the pattern in regex at most limit times, so...
String url="http://myurl.com/users/232222232/pageid";
String[] parts=url.split("/users",1);
//parts={"http://myurl.com","/232222232/pageid"}
String rest=parts[1];
//rest="/232222232/pageid"
The limit is there to prevent strings like "http://myurl.com/users/232222232/users/pageid" giving answers like "/232222232".

You can use String.indexOf() and String.substring() in order to achieve this:
String pattern = "/users/";
String url = "http://myurl.com/users/232222232/pageid";
System.out.println(url.substring(url.indexOf(pattern)+pattern.length()-1);

Problem in replacing special characters in a String in java

I got a String as response from server which is like the below:
hsb:\\\10.217.111.33\javap\Coventry\
Now I want to parse this string in such a way that I need to replace all \ with /.
Also I need to remove the first part of the String which is hsb:\\\
So, my resultant string should be of like this :
10.217.111.33/javap/coventry/
Can anyone help me by providing sample java code for this problem.

Here you have a "dirty" startup "solution":
String s = "hsb:\\\\\\10.217.111.33\\javap\\Coventry\\";
String w = s.replace('\\', '/');
String x = w.replace("hsb:///", "");

String result = yourString.substring(7);
result = result.replaceAll("\\\\", "/");