I have the following code which always gives me java heap space error because of line number 65 due to string buffer append method in this line, I don't know why?
/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
import samy.*;
import java.util.Scanner;
public class InfixToPostfix {
OrderedList list = new OrderedList();
Scanner input = new Scanner(System.in);
public StringBuffer postfix = new StringBuffer();
Due to compatibility reasons, I need to be able to store a random C buffer inside of a Java String. THis means that the Java String should contain the exact same buffer information (i.e. byte sequence) as the original C buffer. How would I do that?
All the functions I found will always somehow code/decode the C buffer, and modify its content depending on the selected encoding.
I need to do this inside JNI. Following is what I have:
Java Code:
unsigned char* cBuffer=getCBuffer();
// Transfer the C buffer to s: jstring s=NULL; if (env->EnsureLocalCapacity(2) >= 0) { jbyteArray bytes = env->NewByteArray(signalLength); if (bytes != NULL)
So I have this file in which has a few sentences on a single line. What I need to be able to do is read the file and then take each word and create a token out of it. Then what it does is it selects the first letter of every 5th word, uppercase it, and then allow me to use append it via a stringbuffer object to create a word out of it.
I know I'll need to use a string tokenizer but I'm not sure how to do so in a way that makes each word separate and how to tell it to only hit the 1st letter of every 5th word.
Here's what I've come up with so far, but I'm currently at a loss at what to do and my textbook/documentation is just not working.
Java Code:
String line; // The line we read from the file. char letter; // The first letter of each 5th word. String sw; // The completed string. public static void main (String [] args)throws IOException {
I am having a bit of difficulty understanding/Using FileWriter. Now by my understanding in the API FileWriter allows to use write at the end of your file, if you have text in there already, correct?
I have a file with people info in it. And I created a GUI which allows people to input that data.
Java Code:
File file = new File("People.txt"); FileWriter fw = new FileWriter(file); People p = new People(firstName, lastName, email, sex)); fw.append(p); fw.close() mh_sh_highlight_all('java');
Now, I keep getting an error on the fw.append(p)
Java Code:
The method append(CharSequence) in the type Writer is not applicable for the arguments(People) mh_sh_highlight_all('java');
i am having a below piece of code in my worker thread. In my output i am getting xml records from the database. I'm sending this output to a input stream & finally to a sax parser.My query is, before sending to the parser i need to store the input stream in buffer. The buffer should store 1000 records. For every 1000 records the parser should be called from buffer.
while (orset.next()) { output = orset.getString("xmlrecord"); writeCount++; InputStream in = new ByteArrayInputStream(output.getBytes("UTF-8")); InputStream inputStream = new ByteArrayInputStream(output.getBytes("UTF-8")); Reader reader = new InputStreamReader(inputStream,"UTF-8");
I'm writing a simple application, that provides a Swing GUI to a bounded-buffer problem. The application is composed by:
- Main.java: it creates a map of four threads (four instances of the class MyThread). Also it creates a shared database (an instance of the class Database) between the four threads.
- MyThread.java: it's an extension of Thread, and it shows a Swing GUI associated to this thread. Each thread is associated a GUI.
- GUI.java
- Database.java: it's an extension of ArrayList and and it can contain a maximum of five elements. An element is an instance of the class User. Also it implements put() and extract() method consistent with the algorithm of bounded-buffer problem.
- DatabaseException.java: it's a simple message.
- User.java
public class Main { public static void main(String[] args) { Database db = new Database(); Map<String, Thread> tdg_m = new HashMap(); for (int i = 1; i <= 4; i++) { tdg_m.put("T" + i, new MyThread(db));
[Code] .....
The issue is the following. When the database is full, and i try to put an element, the GUI freezes. The same problem occurs when I try to extract an element from the empty database.
Normally I would just implement a circular buffer and be happy but there's a fundamental problem with that.OK, so I'm working on a piece of cheap Android hardware that's being used for demo purposes. One of the problems, primarily because it's cheap (imo) is that the screen input is not clean and is interfering with the UI experience. Specifically when gliding your finger, the result is quite non linear.
I know that's not the best drawing but it sort of explains the problem to a degree. In reality, it's probably a bit smoother than that, but there is still noisy data getting in, and the problem is it causes the UI to be jittery at times.
I would like to smooth this using something like a Circular Buffer. Now I figured the best way to do this would be to store the last 4 float inputs and then effectively calculate the next value based on an average, so say our input was this:10, 15, 20, 25 and 35 is the current input.
15 - 10 = 5 20 - 15 = 5 25 - 20 = 5
Then for the next value, 35 - 25 = 10. 10 + (3 * 5) = 25 / 4 = 6.25...Then adding 6.25 to the previous value resulting in this: 10 15 20 25 31.25 which would appear theoretically smoother. However I'm struggling to work out in my head the best way to implement such a function.
How can I write a method that takes a string with duplicates letters and returns the same string which does not contain duplicates. For example, if you pass it radar, it will return rad. Also i would like to know how can I Write a method that takes as parameters the secret word and the good guesses and returns a string that is the secretword but has dashes in the places where the player has not yet guessed that letter. For example, if the secret word is radar and the player has already guessed the good guesses letters r and d, the method will return r-d-r.
I am currently trying to make a calculator in Java. I want to use the String split method to tokenize the string of characters inputted. I thought I was using the String split method wrongly, because I had surrounded the characters I wanted to delimit with square brackets. However, when I removed the square brackets, the code threw an exception when I pressed the equal button. The exception was a PatternSyntaxException exception. Am I using the String split method wrongly? And why is the exception thrown? Here is my code:
import javax.swing.*;//import the packages needed for gui import java.awt.*; import java.awt.event.*; import java.util.Arrays; import java.util.List; import static java.lang.Math.*; public class CalculatorCopy { public static void main(String[] args) {
i am trying to write a class method which will take in a string and returns a string which is the reversed version of that string. it compiles fine but when i try to run it it states Main method not found in class StringReverse,please define the main method as public static void main(String[]args). I am new to java and cannot figure out
import javax.swing.JOptionPane; public class StringReverse { public String reverseString(String str){ JOptionPane.showInputDialog(null,"Please enter word"); char c = str.charAt(str.length()-1); if(str.length() == 1) return Character.toString(c); return c + reverseString(str.substring(0,str.length()-1));}}
Code a Java method that accepts a String array and a String. The method should return true if the string can be found as an element of the array and false otherwise. Test your method by calling it from the main method which supplies its two parameters (no user input required). Use an array initialiser list to initialise the array you pass. Test thoroughly.
public class test { public static void main(String[] args) { Printhelloworld(); String[] verbs = {"go", "do", "some", "homework"}; printArrays(verbs);
So I'm creating a class which when given three inputs uses them as sides of a triangle and tells ther user what type of triangle it is, or if the input is invalid, tells them why it is invalid. I'm readin the input as a string and then trying to split it into a string array, from there checking to see if it has 3 elements.. in which the data is good at that point, and then converting them to ints and checking to see if they're negative ansd finally checking to see if they can work as sides of a triangle ie a+b >c, a+c >b , b+c >a.
I'm trying to split it into an array of strings but am getting an error, and can't seem to figure out why as this should be working from what I've read of the string.split method online.
import java.util.*; public class TriangleTest{ private int sideA; private int sideB; private int sideC; public static void main(String[] args){ TriangleTest triangle = new TriangleTest("3 4 5");
I have a csv file and I want to insert the csv file into the database columns consist of date, description1, description2, amount1, amount2, narration.. but the problem is the narration is coming in second line in csv file due to which the data is not getting inserted into the database. So how to append the narration into the first line,I have enclosed the demo format of csv file and a code to read the csv file..
myFile.csv file:
20-5-2013,"Cash Rec. From abc","pymt",-500.00,, "Cash rec. from abc office",
20-5-2013,"Cash Rec. From xyz","rcpt",-5100.00,, "Cash rec. from xyz office",
How to output text to a file, so I had to do my own research on google, but the results I found were confusing. I finally got my code to write to a file, but I cannot figure out how to append a new line. I know what part of the code is incorrect, but I don't know how to fix it. here is what I have right now:
import java.io.IOException; import java.nio.file.Files; import java.nio.file.Paths; import java.util.Scanner; public class highscore { public static void main(String[] args) throws IOException {
[Code] ....
I can see the last two lines are telling the program to overwrite the first input with the second. Of course if I pick a different file name for the second output, I get another file with the second input, but I need to learn how to append as well.
I know how to append text to a File using the true argument but I would like to be able to append to a certain line In the file.Basically I've made a simple html page with Image links to different sites. I'm trying to make an app that will take a new site as Input and append It to the html file before the </body> tags.
I'm using one method to take input from the user and append some text to it, then I am trying to return the value of the variable and use another method to print it out. But for some reason whenever I try doing this I can't print out anything and I only get a "null" output. Why this is happening?
package Homework3; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class Homework3 {
I am building a little application for personal use where I can track my finance. Now, what I would like to get is an always visible JTable "footer" OR horizontal space field attached to the bottom of the window. The idea is that scrolling down/up wouldn't affect it's visibility(like JTable header). Might a picture tell a thousand words: see attachment.
I am wondering, maybe JTable OR TableModel class has a property to solve this problem(I haven't found any)? Or shall I make another ScrollPane/JPanel? Which path of search shall I pursue?
