Size Of Java Boolean Type In Memory
Jun 13, 2013I searched everywhere but i didn't found anything about the real size of primitive boolean type used by java.
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Using Boolean Data Type In Program
Sep 25, 2014While practicing java i have came across boolean data type. i have executed below program but i am not sure how i got output of the program like below:
10 > 9 is true
Here is my program:
class BoolTest3
{
public static void main(String args[])
{
System.out.println("10 > 9 is "+(10>9));
}
}
My question is: how this program will come to know that 10>9 true or false.. how bolean data type used in this program.
If Statement Requires A Return Of Type Boolean
Dec 6, 2014Im trying to do this
if( 2/2 ) {
system.out.println( "number is not event" );
} else {
system.out.println( "number is event" );
}
However if statement requires a return of type boolean. So im forced to this instead
if( (2/2) != 0 ) {
system.out.println( "number is not event" );
} else {
system.out.println( "number is event" );
}
Is there a way to achieve the former method, without typecasting, if you had to typecast how do you do it?
Rendering Images Of Type BufferedImage - Pixels Are Not Consistent In Size
Jun 26, 2014As implied by the title, when I am rendering images of the type "BufferedImage" unto a Swing application, the images' pixels are not consistent in size. Some might be larger than other, and some might be smaller than other.
Here is a screenshot of what I am talking about (you might need to zoom in a bit because the image is so small): [URL] ....
And here is also some code for you. The images are actually from a sprite sheet, which I first load in its entirety and then split up in an array.
Java Code:
public static BufferedImage sprites[];
...
public void loadSprites(){
try{
BufferedImage bigImage = ImageIO.read(new File("SOURCE/BLA/BLA/THIS/IS/ACTUALLY/NOT/THE/REAL/SOURCE/IN/CASE/YOU'RE/WONDERING/I/JUST/DON'T/WANT/YOU/TO/FIND/ME/AND/RAPE/ME"));
sprites = new BufferedImage[16 * 16];
[Code] ....
So, how do I make the pixels equally small?
Java Memory Matching Game
Feb 13, 2015"A common memory matching game played by young children is to start with a deck of cards that contain identical pairs. For example, given six cards in the deck, two might be labeled
1, two might be labeled
2 and two might be labeled
3. The cards are shuffled and placed face down on the table.
The player then selects two cards that are face down, turns them face up, and if they match they are left face up. If the two cards do not match they are returned to their original position face down. The game continues in this fashion until all cards are face up.Write a program that plays the memory matching game. Use sixteen cards that are laid out in a 4x4 square and are labeled with pairs of numbers from 1 to 8. Your program should allow the player to specify the cards that she would like to select through a coordinate system.For example in the following layout:
1 2 3 4
--------------------
1 | 8 * * *
2 | * * * *
3 | * 8 * *
4 | * * * *
All of the cards are face down except for the pair 8 which has been located at coordinates (1,1) and (2,3). To hide the cards that have been temporarily placed face up, output a large number of newlines to force the old board off the screen.Use 2D array for the arrangement of cards and another 2D array that indicates if a card is face up or face down.Or, a more elegant solution is to create a single 2D array where each element is an object that stores both the cards value and face.Write a function that shuffles the cards in the array by repeatedly selecting two cards at random and swapping them.
Note:To generate a random number x, where 0<= x <1, use x=Math.random();.For example, multiplying y six and converting to an integer results in an integer that is from 0 to 5."I have been thinking about the algorithm and design of the question for a few hours.
Java Error With Boolean To Int
Nov 6, 2014package Week_8;
import java.util.Scanner;
public class Task_1
{
public static void main(String[] args) {
Scanner kboard = new Scanner(System.in);
int customer_number;
String customer;
int items;
char category;
[Code] .....
How To Detect Current Memory Free And Used In Java Program
Aug 29, 2014I would like to know how much of memory is free and used my java program.I have used Runtime.totalMemory and freeMemory() functions. However, how come used memory is so different than java.exe process show in windows task manager?
View Replies View RelatedHow To Avoid OutOfMemory Exception In Memory Intensive Application In Java
Jan 16, 2014We have developed a java application, whose primary objective is to read a file(input file), process it and convert it into set of output files. (I have given a generic description of our solution, to avoid irrelevant details).
This program works perfectly fine when the input file is of 4 GB, with memory settings of -Xms4096m -Xmx16384m in a 32 GB RAM
Now we need to run our application with the input file of size 130 GB.
We used a linux box with 250GB RAM and with memory setting of -Xms40g -Xmx200g (also tried couple of other variations) to run the application and hit OutOfMemory Exception.
At this stage of our project it's very hard to consider redesigning the code to accommodate hadoop ( or someother large scale data processing framework), also the current hardware configuration which we can afford is 250GB of RAM.
Any ways to avoid OutOfMemory Exceptions, what is the general practice when developing these kind of applications.?
Java Heap Memory Error While Writing Large Data To Excel
Mar 6, 2014i have to write more than 100000 rows in a excel sheet (file size more than 20 MB) via java.
when i use XSSF, i am getting below Error.
java.lang.OutOfMemoryError: Java heap space
at org.apache.xmlbeans.impl.store.Saver$TextSaver.resize(Saver.java:1592)
at org.apache.xmlbeans.impl.store.Saver$TextSaver.preEmit(Saver.java:1223)
at org.apache.xmlbeans.impl.store.Saver$TextSaver.emit(Saver.java:1144)
[Code]....
when i use HSSF , i am getting the below Error.
java.lang.OutOfMemoryError: Java heap space
I have tried increasing the java heap size , by giving upto -Xms1500m -Xmx2048m
File System - Managing Secondary Memory Simulated As Byte Array In Java
Feb 11, 2014I and a friend are working with a project to create a file system, who manages a secondary memory simulated as a byte array in Java. We want the file system to be a hierarchical tree structure like in UNIX.
We have come quite far, but the paths are not handled correct. I seem to have mistaken the relative folder ./ for the root folder, but it should mean "working directory folder", ie, where I stand now. That is, if I stand in /dir1 as my "working directory" and make mkdir ./dir2 then should dir2 end up as subfolder in dir1. But with me it appears in the root.
Process 10000 XML Files / Verify And Insert Data Into Database - Java Heap Memory Error
Oct 12, 2013I need to process 10000 xml files and verify and insert the data into database. I am loading all the files in the file object and iterating one by one. I am getting the memory issue. How to handle this?
View Replies View RelatedWant To Know Size Of Object In Java
Mar 11, 2015class Father
{
public int a=5;
private int b=10;
[code]...
what is the size of obj from above code?
Increasing Java Heap Size
Nov 21, 2013I am using a 64 bit Win 7 Pc with 64-bit JVM and we get the error: Java heap space. So we want to increase the Java heap size but not for one application but for every application or in general.
We tried with the java -xmx command but it didn't work...
We tried setting the system variable JAVA_OPTS but again it didn't work...
Why Cannot Change Size Of TextField In Java For Calculator Application
Jan 13, 2014package name;swing library found in javax called to use the graphical contents.
import javax.swing.*;
//creating the contents for the calculator
public class calc {
JButton btn1= new JButton("1 ");
JButton btn2= new JButton("2");
JButton btn3= new JButton("3");
[code]....
I have tried different sizes for the 'TextField' but when I change the size, the position changes instead of the size itself.
JRE :: Reduce Java Runtime Size When Bundled With Application
Mar 31, 2015We are shipping in our company the JRE bundled with the client application in order to ensure the compatibility. But when upgrading from jre6 to jre8 the size increased by 50 MB!
Is there a reliable and secure way to reduce the footprint of the JRE? Are there "light distributions" or a list of libs/files that can be safely removed?
Java Code - Changing Text Size In Windows Settings
Apr 14, 2014I have a major problem. the text size is like 6 or 8 pt font and I can't read it. I'm trying to run a downloaded exe program which uses the jre7 which I had to download beforehand. the font size stays at 6 or 8 even if I try to change it in windows settings. it's a high res monitor on a lenovo yoga laptop. is there a way for me to edit the java code and manually change the font size?
View Replies View RelatedPrint Custom Invoice Of Page Size Using Jasper Report Or IText For Java
Jul 4, 2014I want to print data on invoice receipt size of 20.5 x 14 cm(hard copy). In which I try to put text at some absolute location. I tried iText first. In that I try to set page size by following code. here what is unite used in bracket of rectangle?
Document document = new Document(new Rectangle(552,377));
PdfWriter.getInstance(document, new FileOutputStream("report.pdf"));
document.open();
...
...
...
document.close();
Second I tried Jasper report. In that I set page size to 20.5 x 14 cm. But how can I take value from my java application's textfield and put it in to some absolute location in iReport.As I know jasper report take value from database but how can I take value from java application's textfiled?
I am more familiar with iText. How can I print custom invoice using iText or Jasper Report.I am developing java application using netbeans.
Getting Int Type Cast To Lower Precision Char Type In Parasoft JTEST
Mar 11, 2014Below code I am using to typecast int to char.
char escapeValue = (char)0;
char cha = (char) 10;
escapeValue = (char)(escapeValue * cha); // Here am getting the above error.
I have 38 similar issues in my workspace.
Is Type Irrelevant As Long As Value Is Within Boundaries Of Type Of Switch Expression
Apr 30, 2014If you have final int i = 1;
short s = 1;
switch(s) {
case i: System.out.println(i);
}
it runs fine. Note that the switch expression is of type short (2 bytes) and the case constant is of type int (4 bytes).My question is: Is the type irrelevant as long as the value is within the boundaries of the type of the switch expression?I have the feeling that this is true since:
byte b = 127;
final int i = 127;
switch(b) {
case i: System.out.println(i);
}
This runs fine again, but if I change the literal assigned to i to 128, which is out of range for type byte, then the compiler complains.Is it true that in the first example the short variable and in the second example the byte variable (the switch expressions) are first implicitly converted to an int and then compared with the case constants?
How To Convert Input Array Of Type Strings To Class Type
Aug 14, 2014class Passenger{
String name;
int age;
char gender;
int weight;
public Passenger(){
[Code] ....
This is showing error.....error it gives isthat it cannot change from string type to passenger type......... How to do it??????
Addition Of Generic Type Parameter Causes Member Type Clash
Apr 22, 2014Got a problem with generics, which I'm still pretty new at. Here's a program that compiles fine:
import java.util.ArrayList;
import javax.swing.JComponent;
public class Experiments {
public static void main(String[] args) {
ListHolder holder = new ListHolder();
[Code] ....
It's useless, but it compiles. If I change Line 14, however, to add a generic type parameter to the ListHolder class, Line 10 no longer compiles:
import java.util.ArrayList;
import javax.swing.JComponent;
public class Experiments {
public static void main(String[] args) {
ListHolder holder = new ListHolder();
[Code] ....
I get this error:
Uncompilable source code - incompatible types: java.lang.Object cannot be converted to javax.swing.JComponent
at experiments.Experiments.main(Experiments.java:10)
Apparently, the introduction of the type parameter leaves the compiler thinking that aList is of type Object. I can cast it, like this:
JComponent c = ((ArrayList<JComponent>)holder.aList).iterator().next();
That makes the compiler happy, but why is it necessary? How does adding the (unused) type parameter to the ListHolder class end up making the compiler think the aList member of an instance of ListHolder is of type Object?
How To Convert String Type To Generic Class Type
Mar 22, 2015I have a String repersentaion of some Object.I want that object convert back into some class type how can I do this?
View Replies View RelatedJava Cannot Resolve Word Into Type?
Nov 3, 2014I am creating a user friendly program that allows the user to adjust the dimensions of an oval (painted onto a window) via a 'slider' Everything is fine for the most part, except in the main code- when I tried coding for a window object for some reason java didn't recognize the type (that is, I used the keyword TheWindow and java didn't recognize it) the following is the full code set across 2 classes, but I think the problem is centered around the main class.
package javaIntermediate;
import java.awt.*;
import javax.swing.*;
//NOTE: this is 1 out of 3
[Code]......
Java Array Update Without Using ArrayList - Add Values And Update Size?
Feb 9, 2015I am trying to create an array list without using the built in arrayList class that java has. I need to start the array being empty with a length of 5. I then add objects to the array. I want to check if the array is full and if not add a value to the next empty space. Once the array is full I then need to create a second array that starts empty and with the length of the first array + 1.
The contents of the first array are then copied into the new array without using the built in copy classes java has and then the new array ends up containing 5 elements and one null space the first time round. The first array is then overwritten with the new array containing the 5 elements and the null space. The process then starts again adding values until the array is full which will be 1 more value then recreating the second array empty and the length of the first array + 1. This is my attempt at creating this but I have run into multiple problems where I get only the last value I added and the rest of the values are null:
public class MyArrayList {
public Object arrayList[];
public MyArrayList(Object[] arrayList) {
this.arrayList = arrayList;
[code]...
Recreating Excel Type Database In Java
Jun 25, 2014Ive recently been given a task of recreating an Excel type database in Java.
I need some way of recreating this with a Java form and SQL database.
What the company is doing now is simply opening up the Excel file and filling in the boxes then saving it again.
Here's a sample of a Months entries. Basically just this copy and pasted month after month with Dates changed.
[URL] ....
What I am doing is creating a form that they can input info into daily
[URL] ....
However im not sure how to create a way of presenting the month to month figures continually for years to come.
JRE :: JAVA Downloading As Unknown File Type
Feb 17, 2015I'm a independent IT contractor. On 2 systems this week I've experienced an issue when attempting to download JAVA the file is of an unknown type in IE. See attached. Alternative browsers on the same machine function properly.
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