I saw code like this.
Set<String> set = new HashSet<String>(){{ add("Hello"); }};
I can understand that it is a HashSet with one element "Hello" in it. I don't understand this syntax. Why there are double curly braces?
While analyzing the thread dumps for a performance issue in our java ee web application, I see many thread dumps stuck on a closing brace of a while loop. Here is the code block of a third party library bitronix (version 1.3.3 SNAPSHOT)
public XAResourceHolderState findXAResourceHolderState(XAResource xaResource) throws BitronixSystemException {
Iterator it = resources.iterator();
while (it.hasNext()) {
XAResourceHolderState xaResourceHolderState = (XAResourceHolderState) it.next();
if (xaResourceHolderState.getXAResource() == xaResource)
return xaResourceHolderState;
}
return null;
}
The thread dumps indicate that many threads are stuck in RUNNABLE state on line number 07. What could be the possible reasons on why a thread could get stuck on a closing brace of a while loop? The iterator of the while loop is a custom implementation.
I have read some on this but I'm trying to understand a code and the following part confuses me
if( thisCount == bestCount )
bestCandidates.add( candidate );
else if( thisCount > bestCount ) {
bestCount = thisCount;
bestCandidates.clear();
bestCandidates.add( candidate );
}
}
What I find confusing is this: If I am not mistaken the need for curly braces occurs when using more than one statement and if you use else statements.
So I wonder if I have missunderstood about the else statement and that you dont need curly braces around a one statement if statement that is followed by an else statement...
program to accept string
import java.util.Scanner;
public class accept_string{
public static void main(String[] args)
[code]...
I wrote this program.actually I copy it from webpage this website.Its very cool to wrote programs in java.but I did not understand meaning of string,scanner......
At this moment in time my program compiles and runs as I want it to, but when I look at my code I see that my While Loops braces are placed inside my Try Block. When I move these braces outside of the Try Block, next to the WhileLoop, the program doesn't run like I want it to.
Likewise, when I place the While(answerIsCorrect) inside the Try Block, it doesn't work like I want it to either.
Also, my problem is on Lines 17 and 18.
import javax.swing.*;
import java.util.Random;
public class SwingInputExample
{
public static void main(String args[])
{
int firstNumber=0;
int secondNumber=0;
int correctAnswer=0;
String studentGuess = null;
[Code] ....
i created a class and a constructor for the class. then i used getters and setters.in the setters i'm trying to write a line that will be -
if (num < 0|| num>120) {
dont change value and do nothing
}
else{
num1 = num
}
how can i do this ? i tried to put an empty curly braces but it gives me an error.
what is meaning of Open Source in programming lenguages?
I want to ask this question reagrding this context that if some company or some products that says "This is open source" all codes are available Then it it mean..
1)We can reuse,re produce,distribute this code,modify and sell it for commercial purpose?
I know there is license also attach with a OpenSource.
But What exactly meaning of OpenSource?
this is my code :
String name = "Mohan";
String is a immutable class and where these character stored when we assign some character. How the logics are working inside the String class.
@Override
@SuppressWarnings("unchecked")
public TableCell<S, T> call(TableColumn<S, T> p) {
TableCell<S, T> cell = new TableCell<S, T>() {
@Override
public void updateItem(Object item, boolean empty) {
if (item == getItem()) {
return;
}
The line in the code above TableCell<S, T> cell = new TableCell<S, T>() {
I don't understand how curly braces follow an assignment statement?What does the line of code mean?
I have written the code to read the line from file and save first string as word and and remaining string as meaning..
E.g.: innovation a new method, idea, product, etc.
word = innovation
meaning = a new method, idea, product, etc.
In my code there is no error and have a mistake what it is means first assigning word is ok and while saving meaning ..it saves like
{
a a new a new method } like that
Java Code:
import java.io.BufferedReader;
import java.io.FileReader;
public class Dil{
public static void main(String[] arg)throws Exception
{
BufferedReader in;
[Code] ......
I'm having some trouble with a code I am writing for class. I had an 2 errors like this before this one and fixed it by changing int avgRe, avgMiles =0; to double. Now I am getting this error and am stuck on what I need to change. Here is the code:
import java.io.*;
import java.util.*;
import java.text.*;
public class Reimbursement_3_09 {
static Toolkit tools = new Toolkit();
public static void main (String [] args) throws Exception {
[Code] ....
This is my error:
[code=Java]
Reimbursement_3_09.java:33: error: incompatible types: possible lossy conversion from double to int
summary (outFile, totalAmount, ctrMiles, ctrMilesgt0, avgRe, avgMiles);
^
Some messages have been simplified; recompile with -Xdiags:verbose to get full output 1 error
how can i compare two double values is this correct
Java Code:
public boolean isEqualToD(double s_src, double s_compareTo)
{
boolean flag = false;
try
{
if(s_src == s_compareTo)
{
flag = true;
[code]...
Okey so i want to make an array like this
km = miles
10 6.214
15 9.321
20 12.428
and so on its a converter between km and miles and i have no clue how to do this...
Java Code:
double Compact=30.50;
double Full=40.50;
double discount=.07;
double FullDiscount= 37.67;
double CompactDiscount= 28.37; mh_sh_highlight_all('java');
My question is how do I configure this so that when / if I need to change the discount value, it automatically adjusts the % discount off of the Full or Compact?
All I can get to work is simply hardcoding it and assigning the discount value, i'm probably just messing up the syntax.
ScriptEngineManager mgr = new ScriptEngineManager();
ScriptEngine engine = mgr.getEngineByName("js");
String expres = calc.getText().toString();
calc.setText(expres);
try {
calc.setText(((double)engine.eval(expres)) + "");
} catch (Exception e) {
}
This line: calc.setText(((double)engine.eval(expres)) + "");
*The error message for this line: Cannot cast from object to Double
I am trying to convert the double 4270571936.0000000000d to a hex string using Double.toHexString() and the answer I'm getting is 0x1.fd17834p31, what does p stands for?
The answer I'm expecting to get is 0x41efd17834000000 so not sure why it won't give me the correct answer?
The following floating point Double to hex calculator shows the write answer right Floating Point to Hex Converter
I have a jsf page.i need to confirm one filed only contain double value.how to validate this? I checked and found there is a validateDoubleRange,but its not suitable for this.
View Replies View Related//Students Full Name
firstName = JOptionPane.showInputDialog("Enter student " +
"first name.");
lastName = JOptionPane.showInputDialog("Enter student " +
"last name.");
// Get test grade (numbers)
[b]test1 = JOptionPane.showInputDialog("Enter test1 grade")[/b];
The line in bold is where that error comes up. I know it something simple but I can't remember. I declared both firstName and lastName as Strings and then the test1 I declared as double. I had a similar error in a previous assignment where I had a integer(age) input and then i had an output statement asking for a name all I needed to do was put keyboard.nextLine(); after my age input and I was fine.
I need to understand the java Conversion.
I have a char[] containing ASCII characters that need to be converted into int value and double value.
The int value are always stored in 1 char size like 'j'. I extracted it succesffully by converting the char in a ascii bytearray and then used: Integer.parseInt(sb.toString().replace("0x", ""), 16);
How can I get the Value as double when i used the char[] with size 2 or 4 ?
Example : final char[] charValue = { 'u', ' ', '}','+' }; what is the associate Double value ?
Example : final char[] charValue = { 'T', ' ' }; what is the associate Double value ?
Example : final char[] charValue = { 'T', ' ' }; what is the associate int value ?
I am making a program where the user types in how many students, the student name and the student result. My problem is typing in a dobule name for instance: Tom Tom.
I have tried both:
String name = input.Next(); -> Only works with one name.
and
String name = input.nextLine(); -> Skips right trough and ask me to type result again.
Here is my code:
Java Code:
import java.util.Scanner;
public class c5e8 {
public static void main(String[]args){
Scanner input = new Scanner (System.in);
int highestResult = 0;
String highestName = " ";
[Code] ....
What is the difference between float and double?
View Replies View RelatedI am trying to understand a question:
R2 (x,y) -- Make the Point class code that implements a corresponding abstraction to a given point in R2. You should explicitly provide the manufacturer's code P (double x, double y) for the Point class. And code for the methods, whose definitions are:
- public double getXCoordinate ();
- public double getYCoordinate ();
- public setXYCoordinates (double x, double y);
- public moveTo (double x, double y);
- public printAtts ();
I have a real number. example:
double number = 1.95842175;
I want to split it into 2 integers:
int a1 = 1;
and
it a2 = 95 (2 numbers after '.')
How?
I am working with a java program that uses binary and sequential search. i have those two methods working. In the program i also need to return the price of parallel arrays. This is my code so far:inventory class:
//FileName: InventoryData.java
//Prog: Brock Paston
//Purp: To load and search through arrays with binary and sequnetial search.
package stu.paston.program6;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Scanner;
[code]....
I'm trying to sort 10 inputted numbers (double precision) using the Array.sort() method. I can get the 10 numbers inputted, but the output is ten 0.0s; now (and this how I know I am learning some things) I'm fairly certain that the variable number is not storing the numbers inputted by the user otherwise I wild be seeing the program work correctly.
So my question is why isn't number storing the inputs?
import javax.swing.JOptionPane;
import java.util.Arrays;
public class KrisFrench3 {
public static void main(String[] args) {
double[] number = new double[10];
for(int i = 1; i <= i; i++) {
[Code] .....
I've been programming for a while, but I never made executables... just ran it from the compiler. Now, however, I really want to have an icon for one of my programs that would be conveniently located and clickable. So, I made a jar file, both in Eclipse and BlueJ. When I run this file in command line, it works fine (with "java -jar ..."). In case of Eclipse, this worked with both "jar" and "Executable jar" options. However, when I double click the icon, nothing happens. First I was getting "can't find main class" error, but that was an easy fix with the manifest file. But now, nothing seems to happen at all. Could this be because the program is supposed to run in the command line or whatever the compiler offers and there is nothing to force the computer to open one of those windows?
View Replies View Related