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Why doesn't Integer.parseInt work on a substring?

This conversion is not working, I am getting an exception,
not sure why
String str = "Draw: 1";
int draw = 0;
String temp;
temp = str.substring(5,7);
draw= Integer.parseInt(temp);
System.out.println(draw);

Because you're trying to parse " 1", notice the space. Adding a trim() should solve it.
temp = str.substring(5,7).trim();

Extract last number after decimal

I am getting a piece of JSON text from a url connection and saving it to a string currently as such:
...//setting up url and connection
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String str = in.readLine();
When I print str, I correctly find the data {"build":{"version_component":"1.0.111"}}
Now I want to extract the 111 from str, but I am having some trouble.
I tried
String afterLastDot = inputLine.substring(inputLine.lastIndexOf(".") + 1);
but I end up with 111"}}
I need a solution that is generic so that if I have String str = {"build":{"version_component":"1.0.111111111"}}; the solution still works and extracts 111111111 (ie, I don't want to hard code extract the last three digits after the decimal point)

If you cannot use a JSON parser then you can this regex based extraction:
String lastNum = str.replaceAll("^.*\\.(\\d+).*", "$1");
RegEx Demo
^.* is greedy match that matches everything until last DOT and 1 or more digits that we put in group #1 to be used in replacement.

Find the start and the end indexes of the String you need and substring(start, end) :
// String str = "{"build":{"version_component":"1.0.111"}};" cannot compile without escaping
String str = "{\"build\":{\"version_component\":\"1.0.111\"}}";
int start = str.lastIndexOf(".")+1;
int end = str.lastIndexOf("\"");
String substring = str.substring(start,end);

just use JSON api
JSONObject obj = new JSONObject(str);
String versionComponent= obj.getJSONObject("build").getString("version_component");
Then just split and take the last element
versionComponent.split("\\.")[2];

Please, your can try the following code :
...
int index = inputLine.lastIndexOf(".")+1 ;
String afterLastDot = inputLine.substring(index, index+3);

With Regular Expressions (Rexp),
You can solve your problem like this ;
Pattern pattern = Pattern.compile("111") ;
Matcher matcher = pattern.matcher(str) ;
while(matcher.find()){
System.out.println(matcher.start()+" "+matcher.end());
System.out.println(str.substring(matcher.start(), matcher.end()));
}

Number format issue, newbie project

I am trying to write a program that loads a movie data base file, and then splits up that information into the movie title, year, and all of the associated actors. I split up all of the info, but I am having issues converting the year, which is in a string, to an int. The format of the year string is (****) with the * being a year, such as 1999. When I try to use parse I get a number format exception. I have tried replacing the parentheses, but it just gave me more errors! Any ideas?
public class MovieDatabase {
ArrayList<Movie> allMovie = new ArrayList<Movie>();
//Loading the text file and breaking it apart into sections
public void loadDataFromFile( String aFileName) throws FileNotFoundException{
Scanner theScanner = new Scanner(aFileName);
theScanner = new Scanner(new FileInputStream("cast-mpaa.txt"));
while(theScanner.hasNextLine()){
String line = theScanner.nextLine();
String[] splitting = line.split("/" );
String movieTitleAndYear = splitting[0];
int movieYearIndex = movieTitleAndYear.indexOf("(");
String movieYear = movieTitleAndYear.substring(movieYearIndex);
System.out.println(movieYear);
//this is where I have issues
int theYear = Integer.parseInt(movieYear);
String movieTitle = movieTitleAndYear.substring(0, movieYearIndex);
ArrayList<Actor> allActors = new ArrayList<Actor>();
for ( int i = 1; i < splitting.length; i++){
String[] names = splitting[i].split(",");
String firstName = names[0];
Actor theActor = new Actor(firstName);
ArrayList<Actor> allActor = new ArrayList<Actor>();
allActor.add(theActor);
}
Movie theMovie = new Movie(movieTitle, theYear, allActors);
allMovie.add(theMovie);
}
theScanner.close();
}
output:
(1967)
Here is the errors I am getting:
Exception in thread "main" java.lang.NumberFormatException: For input string: "(1967)"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:481)
at java.lang.Integer.parseInt(Integer.java:527)
at MovieDatabase.loadDataFromFile(MovieDatabase.java:27)

You have brackets around the numbers. You could either correct your file or you could remove brackets using:
String str = "(1967)";
System.out.println(str.substring(1, str.length()-1));
Output:
1967
In your code, you used:
int movieYearIndex = movieTitleAndYear.indexOf("(");
String movieYear = movieTitleAndYear.substring(movieYearIndex);
So if my movieTitleAndYear string is "hi (1947)", indexOf will give me index of "(" as 3 and substring will start reading string from index 3 which includes "(". One way you could avoid opening bracket is to change your substring line to:
String movieYear = movieTitleAndYear.substring(movieYearIndex + 1);//but still you have closing bracket.
If you are sure it's always going to be of four digit, then you could do something like:
String movieYear = movieTitleAndYear.substring(movieYearIndex + 1, movieYearIndex + 5);

You need to add indexof for ")".
Code snippet:
int movieYearOpenBracesIndex = movieTitleAndYear.indexOf("(");
int movieYearCloseBracesIndex = movieTitleAndYear.indexOf(")");
String movieYear = movieTitleAndYear.substring(movieYearOpenBracesIndex + 1, movieYearCloseBracesIndex);
System.out.println(movieYear);
This will give the exact year. e.g. 1967

Your substring call currently gets a year enclosed by brackets, e.g., (1967). You can avoid this by calling the substring variant that accepts an endIndex, and just get the year's four digits:
String movieYear =
movieTitleAndYear.substring(movieYearIndex + 1, // to get rid of "("
movieYearIndex + 5 // to get rid of ")"
);

regex to match and replace two characters between string

I have a string String a = "(3e4+2e2)sin(30)"; and i want to show it as a = "(3e4+2e2)*sin(30)";
I am not able to write a regular expression for this.

Try this replaceAll:
a = a.replaceAll("\) *(\\w+)", ")*$1");

You can go with this
String func = "sin";// or any function you want like cos.
String a = "(3e4+2e2)sin(30)";
a = a.replaceAll("[)]" + func, ")*siz");
System.out.println(a);

this should work
a = a.replaceAll("\\)(\\s)*([^*+/-])", ") * $2");

String input = "(3e4+2e2)sin(30)".replaceAll("(\\(.+?\\))(.+)", "$1*$2"); //(3e4+2e2)*sin(30)

Assuming the characters within the first parenthesis will always be in similar pattern, you can split this string into two at the position where you would like to insert the character and then form the final string by appending the first half of the string, new character and second half of the string.
string a = "(3e4+2e2)sin(30)";
string[] splitArray1 = Regex.Split(a, #"^\(\w+[+]\w+\)");
string[] splitArray2 = Regex.Split(a, #"\w+\([0-9]+\)$");
string updatedInput = splitArray2[0] + "*" + splitArray1[1];
Console.WriteLine("Input = {0} Output = {1}", a, updatedInput);

I did not try but the following should work
String a = "(3e4+2e2)sin(30)";
a = a.replaceAll("[)](\\w+)", ")*$1");
System.out.println(a);

How to print newline when it find \n in a string variable value?

Good Morning,
I had a string value like
Name:Anilbabu\nPlace:Pamarru\nAge::22\n
while printing that string variable.. I don't want to see "\n" in output, Instead, I want to have new line printed like,
Name:Anilbabu
Place:Pamarru
Age:22
Please help me friends, Please give solution in Java.
Thank you.

Use StringTokenizer
StringTokenizer strings = new StringTokenizer(input, "\\n");
while (strings.hasMoreTokens()){
System.out.println(strings.nextToken());
}
OR
use :
System.out.print(input.replace("\\n", "\n"));

Like this
String str = "Name:Anilbabu\nPlace:Pamarru\nAge::22\n"; // the String.
System.out.print(str); // Print the String
Outputs
Name:Anilbabu
Place:Pamarru
Age:22

do like this
String input = "Name:Anilbabu\nPlace:Pamarru\nAge::22\n";
String[] result = input.split("[\\n]");
for (int i = 0; i < result.length; i++) {
System.out.println(result[i]);
}
Output
Name:Anilbabu
Place:Pamarru
Age::22

Just print the value
System.out.println("Name:Anilbabu\nPlace:Pamarru\nAge::22\n");
or Assign it to a variable and then print
String st ="Name:Anilbabu\nPlace:Pamarru\nAge::22\n";
System.out.println(st);