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Java parsing last part of a string

I have three strings.
0:0:0-0:0:1
0:0:0-3:0:0-1:2:0
0:0:0-3:0:0-3:2:0-3:2:1
I am trying to do an exercise where I am parsing the string to output only the last part after the -, i.e. respectively:
0:0:1
1:2:0
3:2:1
I have tried of doing it by getting all the characters from the end of the string up until -5, but that won't always work (if the numbers are more then 1 integer). lastStateVisited is my string
lastStateVisited = lastStateVisited.substring(lastStateVisited.length() - 5);
I thought of splitting the string in an array and getting the last element of the array, but it seems inefficient.
String[] result = lastStateVisited.split("[-]");
lastStateVisited = result[result.length - 1];
What is a way I could do this? Thanks

Try this:
String l = "your-string";
int temp = l.lastIndexOf('-');
String lastPart = l.substring(temp+1);

Since your requirement concentrate around your need of acquiring the sub-string from the end till - appears first time.
So why not first get the index of last - that appeared in string. And after than extract the sub-string from here till end. Good option. :)
String str = "0:0:0-3:0:0-3:2:0-3:2:1";
String reqStr = str.substring(str.lastIndexOf('-')+1);
reqStr contains the required string. You can use loop with this part of code to extract more such strings.

Finding multiple substrings using boundaries in Java

Alright so here is my problem. Basically I have a string with 4 words in it, with each word seperated by a #. What I need to do is use the substring method to extract each word and print it out. I am having trouble figuring out the parameters for it though. I can always get the first one right, but the following ones generally have problems.
Here is the first piece of the code:
word = format.substring( 0 , format.indexOf('#') );
Now from what I understand this basically means start at the beginning of the string, and end right before the #. So using the same logic, I tried to extract the second word like so:
wordTwo = format.substring ( wordlength + 1 , format.indexOf('#') );
//The plus one so I don't start at the #.
But with this I continually get errors saying it doesn't exist. I figured that the compiler was trying to read the first # before the second word, so I rewrote it like so:
wordTwo = format.substring (wordlength + 1, 1 + wordLength + format.indexOf('#') );
And with this it just completely screws it up, either not printing the second word or not stopping in the right place. If I could get any help on the formatting of this, it would be greatly appreciated. Since this is for a class, I am limited to using very basic methods such as indexOf, length, substring etc. so if you could refrain from using anything to complex that would be amazing!

If you have to use substring then you need to use the variant of indexOf that takes a start. This means you can start look for the second # by starting the search after the first one. I.e.
wordTwo = format.substring ( wordlength + 1 , format.indexOf('#', wordlength + 1 ) );
There are however much better ways of splitting a string on a delimiter like this. You can use a StringTokenizer. This is designed for splitting strings like this. Basically:
StringTokenizer tok = new StringTokenizer(format, "#");
String word = tok.nextToken();
String word2 = tok.nextToken();
String word3 = tok.nextToken();
Or you can use the String.split method which is designed for splitting strings. e.g.
String[] parts = String.split("#");
String word = parts[0];
String word2 = parts[1];
String word3 = parts[2];

You can go with split() for this kind of formatting strings.
For instance if you have string like,
String text = "Word1#Word2#Word3#Word4";
You can use delimiter as,
String delimiter = "#";
Then create an string array like,
String[] temp;
For splitting string,
temp = text.split(delimiter);
You can get words like this,
temp[0] = "Word1";
temp[1] = "Word2";
temp[2] = "Word3";
temp[3] = "Word4";

Use split() method to do this with "#" as the delimiter
String s = "hi#vivek#is#good";
String temp = new String();
String[] arr = s.split("#");
for(String x : arr){
temp = temp + x;
}
Or if you want to exact each word... you have it already in arr
arr[0] ---> First Word
arr[1] ---> Second Word
arr[2] ---> Third Word

I suggest that you've a look at the Javadoc for String before you proceed further.
Since this is your homework, I'll give you a couple of hints and maybe you can solve it yourself:
The format for subString is public void subString(int beginIndex, int endIndex). As per the javadoc for this method:
Returns a new string that is a substring of this string. The substring
begins at the specified beginIndex and extends to the character at
index endIndex - 1. Thus the length of the substring is
endIndex-beginIndex.
Note that if you've to use this method, understand that you'll have to shift your beginIndex and endIndex each time because in your situation, you'll have multiple words that are separated by #.
However if you look closely, there's another method in String class that might be helpful to you. That's the public String[] split(String regex) method. The javadoc for this one states:
Splits this string around matches of the given regular expression.
This method works as if by invoking the two-argument split method with
the given expression and a limit argument of zero. Trailing empty
strings are therefore not included in the resulting array.
The split() method looks pretty interesting for your case. You can split your String with the delimiter that you have as the parameter to this method, get the String array and work with that.
Hope this helps you to understand your problem and get started towards a solution :)

Since this is a home work, it may be better to have try to write it your self. But I will give a clue.
Clue:
The indexOf method has another overload: int indexOf(int chr,
int fromIndex) which find the first character chr in the string
from the fromIndex.
http://docs.oracle.com/javase/1.4.2/docs/api/java/lang/String.html
From this clue, the program will look something like this:
Find the index of the first '#' from the start of the string.
Extract the word from 0th character to that index.
Find the index of the first '#' from the character AFTER the first '#'.
Extract the word from the first '#' that index.
... Just do it until you get 4 words or the string ends.
Hope this helps.

I don't know why you're forced to use String#substring, but as others have mentioned, it seems like the wrong method for the kind of functionality you need.
String#split(String regex) is what you would use for such a problem, or, if your input sequence is something you don't control, I would suggest you look at the overloaded method String#split(String regex, int limit); this way you can impose a limit on the amount of matches you make, controlling your resulting array.

Getting a displayed line from a large string

What I want to do is to measure the data of a line on a large string. I am not sure if any has tried this but I have a string which looks like this.
String a =
"This is
kinda
my String"
which would display on android textview as
This is
kinda
my String
Now what I want to achieve is being able get the length of the second line "kinda".
The purpose for this is to be able to set my paging for a book project.
I hope I was clear enough. Thanks for any advice or ideas shared.

Should just be:
a.split("\n")[1].length()

You can use the String function split(String regex)
To split on a "\n"(newline) then use it as a tuple/array and call for any word you want.

Split based on new line indicator.
String lines[] = a.split("\\r?\\n");
int length =0;
if(lines.length >1)
{
length = lines[1].length();
}

I haven't used java in years that being said I'd imagine something like this
String[] temp; //Let's make an array of strings
temp = a.split("\n"); //Split the large string by carriage return
int length = temp[1].length(); //get the length of the 2nd string
Assuming those are \n separating your lines...

How to get perticular digits from the string in android?

I have one String = GETMSG_m_m_5556 from this I want to read only 5556, means I want to read all the digits after last "_". The string has not fixed length of numbers it may be like, GETMSG_m_m_9898786589 OR GETMSG_m_m_98987865. So how can I read the numbers after "_"?
Can anyone suggest me the write way.? It may be foolish question but I am stuck on this. I cant get any idea about this.
Thanks in advance.

String digits = sampleString.subString(sampleString.lastIndexOf("_"),sampleString.lenght);
Get the last index of the char '_' in your string and make a required substring to get the numbers .see string.subString()

You can use the string.split() function and take last string.
String[] separated = yourString.split("_");
// Now choose the last array value

You can try using StringTokenizer
StringTokenizer st = new StringTokenizer(String);
while (st.hasMoreTokens()) {
String s = st.nextToken();
if (s.startsWith("_")) {
....
}}

String Manipulation in java

I have one array of strings. I want to get each of string, divide it in to 3 parts (number-string-number), and put each part in another array. At last I want to have 3 arrays which two of them store numbers and one of them stores strings. The number of spaces between numbers and strings are not fixed.
the format of the strings in the first array is:
-2.2052 dalam -2.7300
-3.0511 dan akan -0.1116
It will be great if you help me with a sample code.

Here's the algorithm you could implement :
Create your 3 output arrays. They should all have the same length as the original string array
iterate through your original array.
for each string, find the index of the first space character and the index of the last space character. (look into the javadoc of the String class for methods doing that)
extract the substring before the first space, the substring between the first and last space, and the substring after the last space. The javadoc should help you.
Convert the first and third substring into an int (see the javadoc for Double for how to do it)
store the doubles and the string into the ouput arrays.

You can use indexOf and lastIndexOf to achieve this. Try following:
String arrayWithStringAndNumber[] = new String[2];
arrayWithStringAndNumber[0] = "-2.2052 dalam -2.7300";
arrayWithStringAndNumber[1] = "-3.0511 dan akan -0.1116";
String numArray1[] = new String[2];
String numArray2[] = new String[2];
String strArray[] = new String[2];
String temp;
for (int i = 0; i < arrayWithStringAndNumber.length; i++) {
temp = arrayWithStringAndNumber[i];
numArray1[i]=temp.substring(0,temp.indexOf(" "));
numArray2[i]=temp.substring(temp.lastIndexOf(" ")+1);
strArray[i]=temp.substring(temp.indexOf(" ")+1,temp.lastIndexOf(" "));
}
Make sure all arrays are of same length.
For num arrays use type whatever you want. I think you may need double and then you can easily parse the value to fit in it.
Hope this helps.

You can use indexOf(int ch) and lastIndexOf(int ch) of String object to find the first and last whitespace character and divide the string using these two indexes. You can also trim the middle string part if needed.
So:
String[] input; // given
Double[] firstNumbers = new Double[input.length];
String[] middleParts = new String[input.length];
Double[] secondNumbers = new Double[input.length];
for(int i = 0; i < input.length; i++) {
String line = input[i];
int firstWhitespace = line.indexOf(" ");
int lastWhitespace = line.lastIndexOf(" ");
String firstNumber = line.substring(0, firstWhitespace);
String middlePart = line.substring(firstWhitespace, lastWhitespace+1);
String secondNumber = line.substring(lastWhitespace+1, line.length());
// parse numbers to double, add to an array
firstNumbers[i] = Double.parseDouble(firstNumber);
middleParts[i] = middlePart;
secondNumbers[i] = Double.parseDouble(secondNumber);
}

Usually every programming language has functions for operating on strings data. Common set of functions is
length (or len) - to get length of string
find (or indexOf or somthing like this) - to find position of character of substring
substring (or substr) - to get substring of N characters from postion P
often
left/right - to get substring of N characters from left or right string's side
Trim/leftTrim/rightTrim - to trim from left and/or right string's side all space-characters or given as function parameter character.
Always as you need to operate on strings data, try to read documentation or google. You always will find information at Internet. Good luck!