Does the following code, which gets a class from a remote server, caches the class on the client machine?
URL u = new URL("http://1.2.3.4:80/JavaClasses/MainClass.class");
InputStream input = u.openStream();
DataInputStream data = new DataInputStream(input);
byte classBytes[] = downloadByteCodesFromURL(data);
Class c = defineClass("MainClass", classBytes, 0, classBytes.length);
[Code] .....
My application loads some 15 Jars from the server, which slows down the entire process.
I need to Load the Jars from a local machine. I want to store the Jar files in the client machine and not in the server.
So that every time when a client need to run my application by a URL specified, the Jar file stored in his system should load.
I had some questions about a theoretical java program. Say you had a java program on a linux server/pc that referenced a folder on that server. And say you had a Client PC (Windows) that had a share folder to that java program.
If that windows client PC tried to run the program would it run (with a GUI if it had one) and would the main directory of the java program still be on the linux server or would it be on the windows computer since that is the computer that is running the program?
Basically I have a program I am trying to find the best way to run it remotely on a windows computer but it references files on the linux server it is located at and needs to put files it creates there as well. I am just trying to make sure I understand my theory here on how the program will run if it IS run remotely.
I am working on SpringMVC web application. Is there any way to detect from browser(jsp page) that any (exe) application is installed or not on client machine? And if not installed then show user the Popup to download that Application or Software . And if the user rejects to download that application then not allow him/her to login ....
View Replies View RelatedWe have web based application (Oracle DB, Weblogic middle tier) and a applet based application running on the browser.
We have a requirement to Load images from the database (stored as blob) to the client browser and the users can do the lookup on images when needed.
We need this to perform well, so there is no delay for the user experience. We have 2 options:
1. Load the images from the database to the Application Server and keep it. When the client request from the browser comes, download it from the application server.
2. Load the images (asynchronosly) when the user logs into the application and download them to the Client machine? Is this possible? Especially give that it is stored in the database as binary objects?
And then load for the user from the client box itself, upon request.
If 2nd option is possible, which once is recommended?
I have developed a code to connecting remote windows M/C from local M/C by using SSH2 (ganymed-ssh2-build209.jar) API. when I run the code its giving below error. Is there any other way to connect remote windows system using java code.
Exception.
java.io.IOException: There was a problem while talking to <host name>:22
at ch.ethz.ssh2.Connection.connect(Connection.java:642)
at ch.ethz.ssh2.Connection.connect(Connection.java:460)
at Connect.RemoteServer.ConnectWindowsServer.runCommand(ConnectWindowsServer.java:55)
at Connect.RemoteServer.ConnectWindowsServer.main(ConnectWindowsServer.java:27)
Caused by: java.net.ConnectException: Connection refused: connect
[Code] ....
JAVA Code
import ch.ethz.ssh2.Connection;
import ch.ethz.ssh2.Session;
public void setAuthenticationInfo(String hostname, String username,String password) {
this.host = hostname;
this.userid = username;
this.password = password;
this.recentCommand = "";
System.out.println("setting authentication info completed for host=" + host );
[Code] .....
I have a requirement where I have to send a file from a local system to unix box(present on client side) using java code.I have developed a code that is successfully sending the file from local system to client side unix box (I am connecting to client side unix box using VPN) provided I run the code in my eclipse IDE present in local system. But when I am running the same code in the unix box it is throwing null pointer exception.Might be the unix system is not recognising the local system. Please find the code.
package abc;
import java.io.File;
import java.io.FileInputStream;
import java.io.FilenameFilter;
import java.io.IOException;
import java.util.Properties;
import com.jcraft.jsch.Channel;
[Code] ....
Error on unix box which I am getting is :-
Inside sftpConnection method
llllllll
fffffffffffff
Connection Successfull
Channel Connection Succesfull
aaaaa
Inside findFile method
Exception in thread "main" java.lang.NullPointerException
at abc.TranferFile.sftpConnection(TranferFile.java:58)
at abc.TranferFile.main(TranferFile.java:21)
Winston Gutkowski in one of the threads that one of the advatanges of String being immutable is that its hashcode could be cached. How does this work? I read somewhere that each String's hashcode is stored in a private int variable, but I don't understand how it is reused.
View Replies View RelatedHow do we cache objects in EJB 2.
My requirement is i need to get data from the database for the first time and retain in cache it throughout the application life.
how a JTable and respective DB table would be updated via directly editing a JTable: After table cell is updated, the setValueAt method of my custom TableModel is called to change the value of the data vector (assume I'm using vectors to store data). setValueAt then calls fireTableCellUpdated which updates the table view, and calls my custom TableModelListener.tableChanged method. Here is where I would write code to update the database.
This means an Update statement is fired each time a cell changes. Sometimes I would like to only send the Update after the entire record has been updated (and a user clicks a Save button).
When we are caching an object, how to set expire time for that object by using pre defined methods?
View Replies View RelatedI am making a little game for my friend based on HTML and javascript and i was wondering how to play an audio file that i downloaded on to my computer without the user interacting. like a buzzer you would hear on jeopordy or something like that, creating a Wrong answer buzzer and a right answer buzzer into an if/else statement.
View Replies View RelatedI would like to ask how with such an array:
x_z01
x_z02
x_q01
x_q02
x_q03
From this table I have searched:
for the
"x_01"
algorithm chosen:
x_z01
for the
"x"
algorithm chose :
"x_z01"
for the
"Z01"
algorithm chose :
"x_z01"
for the
"x_q"
algorithm chose :
"x_q01"
For any character - chose any value from an array
import java.util.Scanner;
/** */
public class Array_value{
/** * @param args the command line arguments */
public static void main(String[] args) {
[Code] ....
Whether this algorithm: [Code] ....
In jsp, In windows 7 , IE 11 , I am able to get the downloaded file but still unable to open it.
View Replies View RelatedI have tried each and every thing in all the other answers. Like setting chunked to false, changing parameters, changing http1.1 -1.0. I am just writing a sample client to compare it with my real time client. Following is the code of client:
package com.webservicemart.ws;
import java.rmi.RemoteException;
import org.apache.axis2.AxisFault;
import com.webservicemart.ws.USZipStub.ValidateZip;
public class UsZipClient {
public static void main(String[] args) {
[Code] ....
And Following is the error :
[INFO] Unable to sendViaPost to url[http://www.webservicemart.com/uszip.asmx]
org.apache.axis2.AxisFault: Transport error: 404 Error: Not Found
at org.apache.axis2.transport.http.HTTPSender.handleResponse(HTTPSender.java:310)
at org.apache.axis2.transport.http.HTTPSender.sendViaPost(HTTPSender.java:194)
at org.apache.axis2.transport.http.HTTPSender.send(HTTPSender.java:75)
[Code] ....
I have tried with other geoIP service and weather forecast too. I get the same error.
I have downloaded the target page's html-file successfully, but how can I find out WHEN that version had its latest update?
Here's how the page is downloaded:
public void dlPage(URL url) {
try {
br = new BufferedReader(new InputStreamReader(url.openStream()));
fileOut = new BufferedWriter(new FileWriter(url.getHost()+".html"));
while( (line=br.readLine() ) != null ) {
fileOut.write(line);
fileOut.write("
[Code
I was thinking of using URLConnection's method getLastModified() for comparison. But dont have a clue how to read it from this file. Am I perhaps solving the download-part incorrectly?
Snapshot downloaded file text:
I wrote a code to download a zip file in jsp, but it is not working as expected, when i execute this following program i am able to download file with "download_all.jsp" name, but now original download file (/tmp/Download_All/1244687508907.Zip). The download_all.jsp is my jsp name which is having the following code. Here is the code snippet:
try {
String filename = "/tmp/Download_All/1244687508907.Zip";
if(request.getParameter("filepath")!=null){
filename=request.getParameter("filepath");
}
// set the http content type to "APPLICATION/OCTET-STREAM
response.setContentType("APPLICATION/OCTET-STREAM");
[code]....
i downloaded a sample database code of an online payroll system. How can i assemble it to know how it works.
the files include php and mysql files. it is to build an online payroll system
How do you call classes within other classes? Or can you only call classes through the main?
View Replies View RelatedIn my JSF application user starts on primary server where the session begins and then the user is redirected to a different server using sendRedirect. I want to pass some authentication token to the next server from primary server. I am trying to set session attribute as:
request.getSession().setAttribute("auth_token", "1");
And then send it to the next server as:
response.sendRedirect(encodedUrl);
But this attribute is not reaching the new server. I cannot pass this auth_token as request parameter as that wont be secure. So how to get some session data to new server?
My output is all over the place. I cancelled out the borderlayouts beneath each panel I created and it completely changed the output, and I'm not sure why. The first photo below, shows what it looked like with the layouts and the second shows the output without. I still don't understand why I don't see the digits 1-9.
Java Code:
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionListener;
public class Atm extends JFrame {
Atm(){
super("ATM");
//Create Panels For ATM
JPanel buttonPanel1 = new JPanel(); //To Contain Digits 1-9
[Code] ....
Why would setting the layout beneath each object change the layout so much? I stayed consistent in my use of BLayout and GLayout in the program.
What is Java Virtual Machine (Java VM)?
View Replies View Relatedkeep getting an error when inventory is printed out. wont carry the money over. cant find out how to do it?
[import java.util.Scanner;
public class VMachine
{
Scanner input = new Scanner (System.in);
double candy;
double soda;
double dsoda;
double money;
[Code] ....
I pulled off an all nighter in order to finish off this project for my computer studies class but i keep getting an error cannot find symbol at line 96?
import java.io.*;
import java.util.*;
import java.util.Random;
public class SlotMachine {
//Generates 3 random numbers for slot machine
public static void main(ArrayList<Integer> slotMachine) {
int count = 0;
while (count<3)
[code]....
I've scanned the book and a few other forums trying to find an answer to my particular question (or I simply didn't understand) with no luck. I want to create an ActionListener for my ATM machine, that will both receive the input numbers to check them against the passcode for a predefined user, but also add the typical " * " that we see when performing such an action.
1. I have created individual objects for each button, which I then used in the constructor "perform" from class action. I'm not sure where to start in the method ActionPerformed.
2. How do I get the asterisks to appear in the JPasswordField each time a numeric button is pressed on the keypad?
Java Code:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Atm extends JFrame {
Atm(){
super("ATM");
//Create Panels For ATM
JPanel buttonPanel1 = new JPanel(); //To Contain Digits 1-9
buttonPanel1.setLayout(new GridLayout(4,3));
[code]....
I am working in software testing, specifically automatic test cases generation. Among the existing forms of test cases, my focus is on the test cases that are composed of sequences of events such as _.event1.event2 eventx()
However, the events can be classified into: sensitive and insensitive. The latter does not affect the system's states, and hence, it can be ignored; while the former affects the states. Anyhow, the sensitive events in the test cases may lead to states explosion and there is a need to prevent that. Therefore, some techniques suggest using one variable to present states and group all similar states together such as using len variable in circular queue. Relatively, the states can be represented by using specific drawings such FSM.
For example, the test cases for circular queue may look like:
add(0).remove().add(1).Front()
add(0).add(1).remove().Front()
which produce the following states:
len=1, rear=0, front=0 and dataQ[0]=0
len=0, rear=0, front=1 and dataQ={0}
len=1, rear=1, front=1 and dataQ[1]=1
len=1, rear=0, front=0 and dataQ[0]=0
len=2, rear=1, front=0 and dataQ[1]=1
len=1, rear=1, front=1 and dataQ={1,0}
As can be seen, every addition/deletion produces a new state. A state is composed of 4 variables: len, rear, front and dataQ. The 1st three variables are integers while the dataQ is an integer array. Nonetheless, the states produced by different test cases can be identical which wastes effort and time. So, there is a need to optimize these states. The search techniques were suggested where the problem can be represented as a search problem and the technique is applied. If we consider Len as a state, then we will have: len=0; 0QSize. However, this does not represent the state but it suits for classifying the states into groups.
In terms of states representation, State Machine/Map Compiler (SMC) was suggested as a modeling mechanism that takes the state machines (i.e. FSM) drawing and generates the code in any preferred language. In SMC, the FSM is represented in a specific syntax (state---transition----next state) and saved in a file (.sm). This file will be compiled by SMC to generate a context class which includes definitions of states, transitions and actions in FSM but still need to be triggered by another class. This class has to call the transitions that modifies the state.
We had created that class and implemented all the methods with their transitions. However, the FSM used was based on 1 variable only (i.e. len). Besides, we are still looking for the SMC results as they will be the input for any search technique to be applied. Supposedly, the states generated by SMC can be used directly in the search technique but this is still questionable.