I am new in java. I executed a java program using eclipse. the program contain two java file. when i try to run it using terminal in Ubuntu. Two files are not linking. it shows error. i am attaching all the data.
It shows the following error
regex2string.java:83: error: cannot find symbol str = randomstr.nextString(2000); ^ symbol: variable randomstr location: class regex2string 1 error
I made a web app to test the ServletContextListener in tomcat according to the book head first servlets and jsps and used the code
out.println("test context attributes set by listener<br>"); Dog dog = (Dog) getServletContext().getAttribute("dog"); out.println("Dog's breed is: "+dog.getBreed());
in the listener class.But the output is showing the first line only and the second println() is not showing any output whereas my Dog class compiled successfully and I didn't see any NullPointerException as expected in the book but somehow it seems like the problem is in the 2nd line of code only but I don't know what.
I also tried to add a 4th line at the end with println() only but with a simple text even that is not running but when I put that same line after the 1st line, the output is shown.I am unable to see what has gone wrong in the 2nd line of code.
I want to access variable of java file into jsp Page. So I tried to do this but it does not work.
Problem : when I am trying to access "getName" method of java class into jsp file it displaying error, i already imported "Ajaxmethod.java" file in to "success.jsp" I want to access "getName" method in to jsp file without creating object of class.
Ajaxmethod.java package a.b; public class Ajaxmethod implements Action{ public String name; public String getName() { return name; }
So say I write up a program like a dice roll game, which I see on the forums here. It's all written and good to go and when I hit Run it does what I want it to do, no errors..What do I do with those .class and .java files? Do I compile it somehow into an app I can put on the google play store? What is the NEXT STEP after the program is all written?
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data.
Here is the base Product class that must be used to create the objects for the array.
public class Product { public String pName; public String stringName; public double price; public int quanity;
[Code] .....
And then here is the data from the text file that i must extract to use to create product objects.
These continue for about 40-50 entries, they are not separated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name separated with spaces, then price after a comma, then quantity after the second comma.....
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data. Here is the base Product class that must be used to create the objects for the array.
public class Product { public String pName; public String stringName; public double price; public int quanity;
[Code]...
these continue for about 40-50 entries, they are not seperated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name seperated with spaces, then price after a comma, then quanity after the second comma.....
I am working on a project that requires me to build a database with random access file, representing products, the base product contains a name (about 30 characters), a price (double), and a quantity (integer). I have worked on this project for probably 15+ hours and have tried so many things and feel like I've barley made any progress...
The part i am really struggling with is taking the data from the text file and creating an object array with it using the product class. Once ive accomplished that, i have to use that data to create a random access file with the data.
Here is the base Product class that must be used to create the objects for the array.
public class Product { public String pName; public String stringName; public double price; public int quanity; //Constructor public Product( String pName, double price, int quanity )
[code]....
and then here is the data from the text file that i must extract to use to create product objects.
Dill Seed,938,34
Mustard Seed,100,64
Coriander Powder,924,18
Turmeric,836,80
Cinnamon (Ground Korintje),951,10
Cinnamon (Ground) Xtra Hi Oil (2x),614,31
Cinnamon (Ground) High Oil (1X),682,19
these continue for about 40-50 entries, they are not separated by a blank line though i had to add those so it would display correctly, each entry is on its own line with name separated with spaces, then price after a comma, then quanity after the second comma.....
I need to write a program that will create an inventory file as a random access file. The problem that I am having is that among the things I need to add to the random access file is a "car name". Since random access files are byte based I don't know how I could possibly write and then read a string value.
I'm given a task to generate an API (a jar file) where the access of a certain database is provided through the API. basic functionality: Client sends a query through the API to server and the Server responds with data.Since its and API, do I have to implement the code or is it enough if i gave just interfaces? what are the OOP concepts to focus on when designing a good API.
I am having hard time to grasp the concept of java as i am beginner. according to different sources found in internet, only one class is written in one source file. and all those class can be accessed through the main class. my question is
1.can we access one class present in one source file, through another class present in another source file [not through the class containing main method]?
2.can we create more than 1 class in same source file?is there special way to do it? i do get error always when i try to do so 3.can multiple classes contain main method? or should there be only single class containing it?
I'm trying to access class file which is inside the package and package is inside the jar file but I can't access that class file inside my source file . All files are on desktop .
I have a random access file stream. I have below code I want to written data that is currently pointed by pointer till the end and display that data on System.out Stream but it is not working my code is
//Create a Random Access File java.io.RandomAccessFile random=new java.io.RandomAccessFile("D:/input.txt","rw"); //Position the pointer to a seek try { random.seek(300); long pointer=random.getFilePointer(); System.out.println("Current Pointer is:"+pointer); int a; while((a=random.read())!=-1) { System.out.println(a); }
Where am I wrong? Although it is returning actual position of pointer in pointer using
I am creating a read/write, RandomAccessFile that I will use to store several student ID and gpa score. What I don't understand is how I should go about retrieving a particular set of data.
public class ReadWrite { static Scanner keyboard = new Scanner(System.in); static String fileName = "Stu.dat"; static RandomAccessFile raf; public static void main(String [] args) throws FileNotFoundException, IOException {
I'm trying to save a picture from byte arrays using RandomAccessFile. The file appears but doesn't open (like its corrupted).
I'm using the bittorent protocol which gives a SHA-1 hash that I compare all the bytes with to verify the data. All the bytes pass the hash check and all the hashes are checked. So I'm pretty sure I'm getting all the bytes correctly.
Is there anything I can do that could tell what's going wrong?
public RUBTClient(final TorrentInfo2 tInfo, final String outFileName) { ... this.outFileName = outFileName; File destined = new File(outFileName); try { destined_file = new RandomAccessFile(destined, "rw"); destined_file.setLength(tInfo.file_length); } catch (FileNotFoundException e1) {
I'm trying to write data for three products to a random access file, but I have a problem. Each product has a code and a price. After writing them to my file, I want to get to the second field or product. I do this by getting the length for each record, and multiplying it by the field number I want to go to. I use the result for the seek() method of the RandomAccessFile object. It is giving me an EOFException, but when I use 0 for the seek method i get the data for the first poduct or field.
Java Code:
public static void main(String[] args) { final int RECORD_LENGTH = 16; try(RandomAccessFile productsOutput = new RandomAccessFile("C:UsersalfonsoDesktopBinaryTestRandom.ran", "rw")) { String[] codes = {"java", "jsps", "txtp"}; double[] prices = {49.5, 19.9, 29.9}; for(int i = 0; i < codes.length; i++) {