When I add an element to my array, I have to make sure that it stays a heap, ie every child is smaller than its parent. However the method that I am using for this, trickling up, is not updating the elements properly, it pretty much just leaves is as is.
Here is the relevant code:
public class MaxIntHeap {
int[] array;
int actualSize = 0;
public MaxIntHeap(){
array = new int[20];
[code].....
in my class is implement a heap and use some of the methods we were provided. The methods I was provided to code and use are "siftDown", "isEmpty" and "heapify". I'm pretty sure the code I have written for "heapify" and "isEmpty" is correct, where I think I am finding fault is the code for my "siftDown". Would you mind taking a look at my code and see why when adding integers to the heap object that I have created in the main code, that they are not being output correctly?
public class Tester {
public static void main(String[] args) {
Heap myHeap = new Heap();
myHeap.insert(9);
myHeap.insert(15);
myHeap.insert(6);
myHeap.insert(4);
myHeap.insert(10);
myHeap.insert(9);
myHeap.insert(3);
[code]....
I am in the process of implementing Priority queue, as I understand that there are many data structures you could use to implement. I implemented it with the an array, which it works absolutely fine. However I have limitations on what collections I can use from the collections classes. I fact I cant use any of the collections classes. Meaning I cant use array.
I’m trying to implement Priority Queue using heap. And implementing heap using binary trees. But however I have a few questions which I need to clarify and I cant think of any other way of resolving it. Ofcourse I can implement my own simple array class using linked list.
Inserting into heap would be quite simple, as I just need to find the right last position from left to right leaf to insert the node into the tree. However after inserting, you may want to make sure that leaf node values are > than root node. Therefore, the root node will always be with the highest priority.
I call these steps where you compare from top down as bubbledown and bubbleup. To do this I really need a for each node within the treee node to have attribute pointing to its root node. So in case of bubbleup I always have a pointer for a given node to its root, without it would mean I would to traverse through the entire tree to identify its root. Which I believe is very inefficient.
Or have I taken this completely wrong? Or is it the case that heap are only best with arrays and therefore use array (by implement it using linked list?)
maximum heap size is set at 1.5GB and consumption of memory at peak load is about 1.1GB. when it reaches 1.1GB, application starts to hang. what could be the problem? shouldn't it be hanging at the point where memory is about equal to the max heap setting? no heap dumps were generated. is this due to server hardware or something? already got the garbage collection data and nothing seemed unusual.
View Replies View RelatedI am learning to use heaps and as an exercise I am trying to write a program using a heap class I have created to sort words. I have read in words from a file and added them to the heap successfully. I am having some trouble figuring out how I can print out a sorted list of the words. From my understanding of how a min-heap works, if I remove from the min/root node they will always be removed in sorted order. So far I have tried out to do a simple for loop but, only half of the heap is being removed. Not sure if my logic is incorrect of there is an error somewhere in my removeMin() function specifically in the while loop.
public static void main(String[] args) {
Heap heap = new Heap();
heap = read( heap );
for( int i = 0; i < heap.getSize(); i++){
heap.removeMin();
[Code] ....
What is the ratio of Memory(RAM) to heap space ? ie: When JVM will throw OutOfMemoryError based on heap available to JVM ?
OutofMemoryError - Memory:RAM size
I 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...
I have two unix systems in which on one system I installed sun solaris jdk and on another system I installed IBM jdk.
Java programs which consume more heap memory are getting failed on sun solaris jdk system where as same programs are successfully getting executed on IBM jdk system .
My question is does sun solaris 64 bit jdk needs more heap than IBM 64 bit jdk ??
When I try to write the .xlsx file using apache POI, XSSFWorkbook API and run this program in Eclipse STS, I am getting the java.lang.OutOfMemoryError: Java heap space error. Then I searched the net and add these -Xms512m -Xmx1024m in the eclipse VM arguments. Even though I am getting the same error. Again i increase heap size but i am getting the different error like "occurred during initialization of VM, Could not reserve enough space for object heap". how to increase the heap size or any other API to read, delete and write the .xlsx file. I am having 4GB ram in my machine. Apache POI is very good for .xls but if it is .xlsx performance wise it is very slow.
View Replies View RelatedGiven a string, compute a new string where identical chars that are adjacent in the original string are separated from each other by a "*". My implementation :
package com.tcs.dash;
public class StringBuild {
public String edit(String userIp){
StringBuilder builder = new StringBuilder(userIp);
String replaceText = "";
for(int i = 0; i < builder.length() - 1; i++){
if(builder.charAt(i) == builder.charAt(i+1)){
replaceText = builder.charAt(i) + "*" + builder.charAt(i+1);
builder = builder.replace(i, i+1, replaceText);
}
}
return builder.toString();
}
}
I am getting error at line 13. An exception actually.
I/P given = aaaa
Console:
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
at java.util.Arrays.copyOf(Unknown Source)
at java.lang.AbstractStringBuilder.expandCapacity(Unknown Source)
at java.lang.AbstractStringBuilder.ensureCapacityInternal(Unknown Source)
at java.lang.AbstractStringBuilder.replace(Unknown Source)
at java.lang.StringBuilder.replace(Unknown Source)
at com.tcs.dash.StringBuild.edit(StringBuild.java:13)
at com.tcs.dash.StringBuildExample.main(StringBuildExample.java:14)
I have a simple JavaFX Application that open a Browser and shows google page. After exit the Application and free all objects, I can see that the JavaFX objects like Scene, Stage, WebView and WebEngine are alive in the heap memory after call GC. I can see this objects with JProfiler and other Profiler tools.
This is my Test code:
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javafx.application.Application;
import javafx.application.Platform;
[Code] .....
And my JavaFX Application:
import javafx.application.Application;
import javafx.geometry.HPos;
import javafx.geometry.VPos;
import javafx.scene.Scene;
import javafx.scene.layout.Region;import javafx.scene.paint.Color;
[Code] .....
To test the application click on Start Button to show google web page, click on Stop Button to stop the application, run a Profiler tool, and call gc, the JavaFX classes are alive. I am using java version "1.7.0_51" and windows 8.1 Is there something wrong in my code? Or this is the normal behavior?
I was wondering where is the memory allocated for an applet; by the browser; by the JVM; some applet specific java option? I get an out of memory error when running my applet (loading pictures).
View Replies View RelatedProperties info = new Properties( );
info.put( "user", "username" );
info.put( "password", "password" );
Connection conn = DriverManager.getConnection(URL, info);
I am using simple jdbc connection to connect to Sybase as shown above , problem is security team is able to see password as clear text in heap, How to avoid it.
I am working on program and have been struggling to get around step 5 and 6 given below.
I have got on with the first couple of points. Where to begin with steps 5 and 6.
Java Code:
class Hourglass {
int height;
int bottomHalf;
public Hourglass (int h) {
height =h;
}
public Hourglass (){
height=3;
}
/*Write a method dropGrain that simulates one grain of sand falling into the bottom half of the Hourglass. If all the sand is already at the bottom before a grain is dropped, this method should cause the hourglass to be flipped, meaning that all the sand will be in the top again. Then, one grain of sand should fall. */
//Hint: this method can be quite short. All you need to do is update one attribute.
public void dropGrain(){
}
/*Write a method getHeapHeight() which returns the height of the heap of sand in the bottom of the hourglass.
Hint: a triangle of height h contains h*h grains (=1+3+5+...+h).
So determining the height when the amount of sand in the bottom half is a square (1,4,9,16,...) is easy. Think about what happens if the amount of sand is not exactly a square.*/
public int getHeapHeight() {
} mh_sh_highlight_all('java');
I am not a java developer, but I am using a java code that was available online to convert a large XML file to CSV file. The input file size is big, it is around 3GB. I got an error that it is out of memory, it is expectedly due to the large input file that i am trying to convert. Splitting of this file is not possible,
This is what I ran : xml2csv-conv data.xml data.csv
Error:
Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
at com.sun.org.apache.xerces.internal.dom.DeferredDoc umentImpl.createChunk(Unknown Source)
at com.sun.org.apache.xerces.internal.dom.DeferredDoc umentImpl.ensureCapacity(Unknown Source)
at com.sun.org.apache.xerces.internal.dom.DeferredDoc umentImpl.createNode(Unknown Source)
at com.sun.org.apache.xerces.internal.dom.DeferredDoc umentImpl.createDeferredTextNode(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.Abstrac tDOMParser.character
[code]....
Additional information: I am running this from a Windows8 64 bit machine with 8GB physical RAM.
i 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
I have a question regarding the permissions set for generated heap dumps.
I have some Jetty servers running on Linux (Java 6 64 bit / Java 7 64 bit) with the following Java arguments:
-XX:+HeapDumpOnOutOfMemoryError
-XX:HeapDumpPath=/opt/apps/heapdump
When there is a out-of-memory exception a heap dump is automatically generated by the JVM. But it seems that the heap dump permisions are set to read-write for owner only (600).
When I create files then they have by default read-write for owner and group/all read access (644).
$ ls -l
total 795432
-rw------- 1 bamboop bamboo 811322265 Apr 14 09:18 java_pid337.hprof
-rw-r--r-- 1 bamboop bamboo 6 Apr 14 12:57 test
Here the umask set for the server running the Java processes
$ umask
0022
I 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 RelatedI am using JSF2 with Primefaces. Here is my business requirement-Hidden field on JSF page should take the value from the session object that is set in managed bean. Session object is updated every time when the user submits the page. I am able to update the session object in the managed bean and able to get the value in the hidden field first time and after that i see the same value in the hidden field even though session object has different value. Here is the hidden field: <h:inputHidden id="xyz" value="xyz"/> i tried using sessionScope but still didn't work.
View Replies View RelatedI have a jTextPane set up and a panel with radioButtons. My jTextPane displays the contents of a text file I have chosen. The 3rd line, 4th index, displayed in my jTextPane specifies a value of type int. When I click my radioButton, I would like that value to increase by 1. So far, I have the following code. I tried to pane.setText(value + 1), but that doesn't seem to work. How do I update the value and display the updated value in jTextPane?
My code :
private final ActionListener actionListen = new ActionListener() {
for(String line: pane.getText().split("")){ String lineThree = line[3];
int value = lineThree.charAt(4); if(radioButton.isSelected()){
pane.setText(value+1); } }};
The program runs well , it adds the applet but it dosn't update the interface unless I press "_"(Minimize) . To be more clear , the object paints a spring wich goes through 4 stages , it is added to the JFrame but it dosn't uptade until I minimize the frame , that is when it goes to the next stage .
The main class which calls the spring to be added to the frame :
public class principal implements ActionListener ,Runnable{
JTextField field;
JFrame frame;
private class Action implements ActionListener {
public void actionPerformed(ActionEvent event) {
frame.repaint();
[Code] .....
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
[Code]....
I am trying to Make A GUI which has a Jcombo box i also want it to have a jlabel that up dates depending on which option the user selects from the JcomboBox
for exampl if i select lion i want it to say you chose lion on the Jlabel and if i choose ostrich i want it to say ostrich and so on
I have two images. I want to be able to click them and kick off a call to a listener in Java to change a value in the bean. I also want the view to update my dropdown (labeled "menuModel") to either be rendered or not, depending on which image I click. Alternatively, I would be fine with the dropdown simply being disabled and enabled for the same criteria.
So far, the listener kicks off fine, and the value gets updated correctly in the bean. However, the view never gets updated. I have tried this a hundred different ways, but nothing seems to work. If I hit refresh on my browser, the view updates. But I want it to do it automatically.
I am using standard JSF 2.1.
<div style="font-family: Verdana; font-size: 10pt; color: #FFFFFF">
<h2>Calibrations</h2>
<h:form id="tunerSelectionForm" style="color: #000000">
<h:commandLink>
[Code] .....
I have loaded the combo box at starting of program.When i am adding the element to combo box through database it's not updating visually.But the inserted data is successfully loaded in List.
void update_Attan() {
DefaultComboBoxModel nm = new DefaultComboBoxModel(new StudentMethods().update_combo_AttendanceType());
cmbStdAttType.setModel(nm);
}
Why the Progress Bar is not Working in Second attempt?When i am Invoking Below Method on actionPerformed at first attempt its Working Fine but After that Its Not Working at all....
void initWait() {
go.setEnabled(false);
browse.setEnabled(false);
choice.setEnabled(false);
wait.setVisible(true);
wait.setMinimum(0);
wait.setMaximum(Info.getMp3().length);
System.out.println(Info.getMp3().length);
wait.setStringPainted(true);
[code]...
for a better Understand see this Mp3Arranger.jar or see the Whole Project SourceCode
My program is working fine. When I executes it, it shows me this:
The clock is 54 minutes over 23 (+41 seconds.
and when i press ENTER, it shows me this:
23:54:41
But then it won't show me the update. I want to update the time, for example when I started the execution the time was 23:54:41 but it must show me something like 23:54:45, because I need the current time.
I have searched the whole internet about this but I don't know how to use the "Date.update ();".
Here is my code
package p2;
import java.util.Calendar;
import java.util.Date;
import javax.swing.JOptionPane;
public class Time {
public void myTime() {
Calendar cal = Calendar.getInstance();
[Code] ....