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Splitting string with similar starting pattern

So, I've been trying to split something I'm reading from a file. But everything that I've tried does not give me only the part that I want.
What I have as string is this:
Scenario:
Bunch of stuf here
Just typing stuff for the example...
Scenario:
More stuff here
A lot more stuff here
XX123
I want to get everything from 'Scenario:' to 'XX123'
Like this:
Scenario:
More stuff here
A lot more stuff here
XX123
The file that I'm reading from have a lot of those 'Scenarios:' and using Pattern from java doesn't give me only the part that I want. Instead it gives from the first 'Scenario:' it finds until 'XX123'
I also tried to use StringUtils.substringBetween, same result.
Thanks in advance

The old-fashioned way to do it would look something like this:
String inputText;
String END_MARKER = "XXX123";
int indexOfEnd = inputText.indexOf(END_MARKER);
// search in reverse
int indexOfScenario = inputText.lastIndexOf("Scenario", indexOfEnd);
String result = inputText.substring(indexOfScenario,
indexOfEnd + END_MARKER.length());

How to replace xml empty tags using regex

I have a lot of empty xml tags which needs to be removed from string.
String dealData = dealDataWriter.toString();
someData = someData.replaceAll("<somerandomField1/>", "");
someData = someData.replaceAll("<somerandomField2/>", "");
someData = someData.replaceAll("<somerandomField3/>", "");
someData = someData.replaceAll("<somerandomField4/>", "");
This uses a lot of string operations which is not efficient, what can be better ways to avoid these operations.

I would not suggest to use Regex when operating on HTML/XML... but for a simple case like yours maybe it is ok to use a rule like this one:
someData.replaceAll("<\\w+?\\/>", "");
Test: link
If you want to consider also the optional spaces before and after the tag names:
someData.replaceAll("<\\s*\\w+?\\s*\\/>", "");
Test: link

Try the following code, You can remove all the tag which does not have any space in it.
someData.replaceAll("<\w+/>","");

Alternatively to using regex or string matching, you can use an xml parser to find empty tags and remove them.
See the answers given over here: Java Remove empty XML tags

If you like to remove <tagA></tagA> and also <tagB/> you can use following regex. Please note that \1 is used to back reference matching group.
// identifies empty tag i.e <tag1></tag> or <tag/>
// it also supports the possibilities of white spaces around or within the tag. however tags with whitespace as value will not match.
private static final String EMPTY_VALUED_TAG_REGEX = "\\s*<\\s*(\\w+)\\s*></\\s*\\1\\s*>|\\s*<\\s*\\w+\\s*/\\s*>";
Run the code on ideone

Java: reading a string in a particular format

I am not posting any code I am struck with. I am trying this in Java:
Issue:
I have words like:
,xxxx-1223
yyyyy,xxdd-345
$,xxxxr-7
sdsdsdd-18
so what ever format I have I should be able to read the last one:
xxxx-1223
xxdd-345
xxxxr-7
sdsdsdd-18
what so may be the words, all I need to to get the words as shown.

Use String#lastIndexOf(int) to find where the last comma occurs, and use String#substring(int) to get the rest of the string that follows.
String input = /* whatever */;
int lastComma = input.lastIndexOf(',');
String output = input.substring(lastComma + 1);

String[] str=yourWord.split(",");
String output=str[str.length-1];

You can use this Regex: -
(\\w+-\\d+)$
Or this specific problem can simply be solved using String.split() or String.substring(int) methods

Add exact number of spaces to start of string using java.util.Formatter

I am using Formatter to output Java code to a file. I want to add a specific number of spaces to the start of each line. My problem is I cannot find a way to do this "neatly". The standard options seem to only allow adding a minimum number of spaces but not a specific number of spaces.
As a work around, I am currently doing the following:
out.format("%7s%s", "", "My text"); but I'd like to do it with only two arguments like this out.format("%7s", "My text");.
Does anyone know if there is a way to do this using the standard Formatter options?

I'm not exactly sure what you want here:
out.format("xxx%10sxxx", "My text");
// prints: xxx My textxxx
While:
out.format("xxx%-10sxxx", "My text");
// prints: xxxMy text xxx
As far as I know, there is no way to do the old C-style formatting to specify the size in an argument like "%*s" because then you could pass in (str.length() + 7).
I'm afraid that your way seems to the the most "neat". If you can explain why you don't like it maybe we can find a better workaround.

You can prepend text into your string.
Another way to reapet any string which you can use this code:-
String str = "abc";
String repeated = StringUtils.repeat(str, 3);
here StringUtils is org.apache.commons.lang3.StringUtils class.

Use Commons Lang
String line = "Hello World!";
int numberOfSpaces = 2;
String lineWithSpacePadding = StringUtils.leftPad(line, line.length() + numberOfSpaces);

Java regular expression for extracting the data between tags

I am trying to a regular expression which extracs the data from a string like
<B Att="text">Test</B><C>Test1</C>
The extracted output needs to be Test and Test1. This is what I have done till now:
public class HelloWorld {
public static void main(String[] args)
{
String s = "<B>Test</B>";
String reg = "<.*?>(.*)<\\/.*?>";
Pattern p = Pattern.compile(reg);
Matcher m = p.matcher(s);
while(m.find())
{
String s1 = m.group();
System.out.println(s1);
}
}
}
But this is producing the result <B>Test</B>. Can anybody point out what I am doing wrong?

Three problems:
Your test string is incorrect.
You need a non-greedy modifier in the group.
You need to specify which group you want (group 1).
Try this:
String s = "<B Att=\"text\">Test</B><C>Test1</C>"; // <-- Fix 1
String reg = "<.*?>(.*?)</.*?>"; // <-- Fix 2
// ...
String s1 = m.group(1); // <-- Fix 3
You also don't need to escape a forward slash, so I removed that.
See it running on ideone.
(Also, don't use regular expressions to parse HTML - use an HTML parser.)

If u are using eclipse there is nice plugin that will help you check your regular expression without writing any class to check it.
Here is link:
http://regex-util.sourceforge.net/update/
You will need to show view by choosing Window -> Show View -> Other, and than Regex Util
I hope it will help you fighting with regular expressions

It almost looks like you're trying to use regex on XML and/or HTML. I'd suggest not using regex and instead creating a parser or lexer to handle this type of arrangement.

I think the bestway to handle and get value of XML nodes is just treating it as an XML.
If you really want to stick to regex try:
<B[^>]*>(.+?)</B\s*>
understanding that you will get always the value of B tag.
Or if you want the value of any tag you will be using something like:
<.*?>(.*?)</.*?>