Unbuffered I / O Requests Send To CD Driver
Feb 25, 2014I want to write java code which can block unbuffered I/O requests send to CD driver ...
View RepliesI want to write java code which can block unbuffered I/O requests send to CD driver ...
View RepliesUsing Java 7 update 5 (I know it's old...), we are trying to send concurrent requests to a RMI Server. When we start to tamp up the load (not too much - up to 50 concurrent requests) we start to see many IO Problems like Broken Pipe and Connection Reset By Peer. Could we be hitting some unknown limitation on concurrent access? Is there such limitation?
View Replies View RelatedI did a Servlet and a JSP with a combobox. I called the JSP on one browser and selected value n1 from the combobox. From another computer, I called the (same URL) and selected value n2. I expected the Servlet to handled both requests separately, however when I select value n2 on the 2nd browser, the jsp on the 1st browser that initially had value 1, now changes into value 2 as well.
Why cant the servlet handle requests separately? users actions on different browsers should not interfere with each other..!
Generally Socket Programming uses HTTP Protocol to send and receive messages in Java. Can we try to exchange HTTP/HTTPS requests instead of TCP?
a Socket constructs a HTTP request to send to another socket from information it has and sends to another one and Server responds with HTTPResponse.
I've written an HTTPServlet that send an HTTP request to one HttpListener and receive POST requests from an Http Sender.This is the code:
package sspa.huvr.git;
import java.io.DataOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Date;
[code]...
but when is called from the doPost method it seems that the html content is not sent from the processRequest method.
Is it possible to send a duplicate soup request?Basically, I have a situation where two almost identical requests can get sent but right now the response comes back as one response. I wanted visibility to the two responses and the one gets dropped off
View Replies View RelatedI had to change context path name of my web application due to some organizational shuffle. I have successfully changed it and it has been working fine.
But what is happening is we have used old context path name in reminder and notification emails. so When users hit links from old emails, they are getting 404 Error.
Is there any way to redirect the old request which has old context path to new one?
How does jsp create session when there're two requests coming simultaneously from the same client browser(maybe one tab maybe two tabs)?
I ask this question because it is said jsp could solve DuplicateSessionException in flex.
[URL] ....
if so, jsp would create same session(with same session id) for the two requests coming simultaneously?
I have written the following code to handle multiple Client Request. Lets Assume that it takes server 300 nano seconds(ns) to process one connection request. It recieves two connection requests at time t1 and t1+200ns. Since server is busy handling request 1 at time t1+200ns. what will happen to request 2.if yes what is the max size of that buffer?Maximum number of request that a server process per unit time depends on the java code.Is there also a limit to how many request a server can recieve per unit time?
public class EchoServer
{
public static void main(String args[])
{
ServerSocket serverSocket = null;
BufferedReader readSocket = null;
PrintStream writeSocket = null;
serverSocket = new ServerSocket(9998);
[code]...
Is there any kind of way to generate HTTP request within a servlet, dispatch it to the server and get back the answer delivered to the servlet? Or are the servlets meant only to respond to passed requests, not generate them?
(I asked a similar question here: [Code] ..... but no luck)
Where do I have to put the ojdbc6.jar file so that Java finally recognizes it?I'm trying to connect to a Oracle XE databse from a Java application, but
Class.forName("oracle.jdbc.OracleDriver");
Will throw a ClassNotFoundException no matter where I put the driver. Stuff like this should be extremely simple but I am about to give up for good now.
Why we create a driver class?Instead of creating a driver class, if we want to compile our code so will it show output? Let say, we've created a class GradeBook of the institution for students.So they can easily view their profile information and scores in different semesters.so when we have created a class for this purpose, should we create a driver class or not?What is the big advantage of creating a driver class?
View Replies View RelatedI'm trying to use a setter method to pick a random integer to be the MPG for a car. However, I'm having major issues in my driver when trying to use that random number in an instance. I'm not finished with the driver yet because I keep getting "cannot find symbol errors"
import java.util.Random;
public class Car {
private String make;
private String model;
private int year;
private int mpg;
private int odometer;
Random generator = new Random();
[code]...
I am having trouble creating a driver for the following program. im new to creating interfaces and i need to make this work.
Lockable interface:
Java Code:
public interface Lockable {
boolean locked();
public void setKey(int key);
public void lock(int key);
public void unlock(int key);
} mh_sh_highlight_all('java');
[code]....
I started learning mysql to connect my program to a database but every time i try to connect I get this error.
java.sql.SQLException: No suitable driver found for dbms:mysql://localhost:3306/apexdemo
at java.sql.DriverManager.getConnection(DriverManager.java:596)
at java.sql.DriverManager.getConnection(DriverManager.java:215)
at JDBCdemo2.main(JDBCdemo2.java:7)
I did the following:
- added the mysql-connector-java-5.1.34 jar to my classpath
- added mysql jdbc driver to the project library
- double checked the url syntax and spelling errors
- checked that the server is running
import java.sql.*;
public class JDBCdemo2 {
public static void main(String[] args) {
Connection conn = null;
[Code] ....
I came across the below
1) When a variables are declared "Private" How should it be accessed from the driver class ? Sometimes i get an error in driver class saying "your variable is declared Private" why am I getting this error ...
The document says "Private" declared variables should be accessed only through methods. What does that mean.
I wrote a couple classes and am trying a test driver but it is having an error I do not know how to solve.
Student Class:
public class Student{
private Course[] courseList;
private static int numCourses;
private final int maxCourses;
public Student(int max){
maxCourses = max;
[Code] .....
Error:
javac tester.java
tester.java:6: error: cannot find symbol
one = new Course(name);
^
symbol: variable name
location: class tester
1 error
Same issue, just only one error as there is only one line. It seems like it does not accept my parameters as it cannot find symbol.
I forgot to put the "" in the brackets, it's been a month since I have looked at any java and made this simple mistake.
public class Car
{
//instance variables ----------------------
private String make;
private String model;
private int year;
private double vehiclePrice;
private double downPayment;
private double milesPerGallon;
[code]....
I created this class "Car" (also not sure if it's correct) and need to write a driver program that creates two instances of the class Car. One must use the default constructor, and the other must use the non-default constructor. It must demonstrate the methods used in the Car class using those instances.
public class DriverCar
{
public static void main(String[] args) {
Car car1 = new Car("Toyota", "Corolla", 2013, 20000, 3000, 35);
Car car2 = new Car("Ford", "Taurus", 2005, 14000, 1500, 25);
System.out.println(car1);
[Code] ....
I need to access Oracle database without using ODBC driver using DAO only, how to do that...
View Replies View RelatedAssignment:
Create a class; call it Lab4a that will have one method called pull. This method does not return anything and requires no parameters.
-In the method, create three random integers in the range 1 to 7. The method will then display the three numbers to the terminal window.
-Now create a driver program, called SlotMachine, to invoke the pull method of the Lab4a class.
-As a refresher, you will have a main method in the driver class that will create an object of Lab4a and then use the only method of this object.
-In your driver program, invoke the roll method 10 times.
-See the back of this lab for an example of the output.
This is what I have so far.
Slot machine
import java.util.Random;
public class Lab4a {
public static void main (String[]args) {
Random pull=new Random();
[code]....
Okay, so I have to create a class with instance data and instance methods.
First, BankAccount class. It should contain the following information, stored in instance variables:
First name: The customer's first name.
Last name: The customer's last name
Balance: The amount of money the customer has in the account.
It should have the following methods:
BankAccount(String firstName, String lastName,
double openingBalance)
This constructor creates a new BankAccount
public String firstName()
Returns the customer's first name
public String lastName()
Returns the customer's last name
public double balance()
Returns the customer's account balance
Finally I need to create a driver to test my class. And create several accounts and verify that the first name, last name, and balance methods work properly. This is my code below.. I don't know if I did it right.
public class BankAccount {
String firstName, lastName;
double balance;
public BankAccount(String firstName, String lastName, double balance) {
[Code] .....
I'm working on an application I made a few years ago. At that time I connected to a local database so my address was 'jdbc:mysql://localhost:3306/'. That database is long gone so I recreated it on one of my hosted servers but I'm a little unsure of how to connect to it. At the moment I'm trying "jdbc:mysql://www.mydomain.com:3306/" but it is giving me an access denied error.
java.sql.SQLException: Access denied for user 'myusername'@'c-[my-ip].hsd1.pa.comcast.net' (using password: YES)Every result on Google seems to use localhost so I'm having a little difficulty figuring out the correct format.
I am to create a Array class then create a Driver class (TestArray) to test all the methods in the Array Class. Here's the code i've written for the Array Class. I just nee developing the TestArray class.
import java.util.Scanner;
public class Array
{
Scanner sc = new Scanner(System.in);
private double[] array = new double[];
public void setArray(double[] arr) {
[Code] ...
I have a driver and a main program. How would I go along with calling the encode method to the driver class that I made so I can have the user inputs affected by the encode method?
Java Code:
public class ShiftEncoderDecoder
{
private int shift;
public ShiftEncoderDecoder(int shift)
{
setShift(shift);
}
public int getShift()
[Code] ....
This the output of java from my PC under linux platform (rhel 6.5).
[pentaho@vertica-srv1 Downloads]$ java -version
java version "1.7.0_79"
Java(TM) SE Runtime Environment (build 1.7.0_79-b15)
Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)
[Code] ....
But the problem is while trying to open ETL program under linux platform [pentaho@vertica-srv1 data-integration]$ ./spoon.sh .... I received the following error messages.
[pentaho@vertica-srv1 data-integration]$ ./spoon.sh
Trying to add database driver (JDBC): RmiJdbc.RJDriver - Warning, not in CLASSPATH?
Trying to add database driver (JDBC): jdbc.idbDriver - Warning, not in CLASSPATH?
Trying to add database driver (JDBC): org.gjt.mm.mysql.Driver - Warning, not in CLASSPATH?
Trying to add database driver (JDBC): com.mckoi.JDBCDriver - Warning, not in CLASSPATH?
[KnowledgeFlow] Loading properties and plugins...
We have a java application in our production enviroment using Spring framework which is configured with DBCP connection pool and the backend is Oracle database( version 11.2.0.3). Recently we encountered an occasionally happened situation(about once every week) and can be described as below:
The application schedules a task that runs every 10 minutes. And during task execution, the application would issue a SQL query of which the result is expected to be got within 10 seconds. At 11:51 a.m Oct 13th, however, the application failed to get the result within expected time, and 2 hours later, at 13:51, the result was finally returned to application. Due to lack of information at that time, we were not able to reproduce the same problem in test environment. At 15:31 p.m, Oct 29th, it happend again and this time we grasped all the information including thread dump and Oracle diagnostic information. We could found that:
1. Through oracle v$sql view, we could find that the SQL query is executed twice, at 15:31 and 17:31 respectively.
2. By analyzing TCP packets provided by network monitoring tools, it can be concluded that the request TCP packet containing SQL statement had been sent to Oracle and get executed, but after that JDBC only fetched first 80000 records out of 90000 records in total and then it stopped, didn't send any more request to Oracle to fetch rows. 2 hours later, Oracle sent a TCP keep alive packet and JDBC driver resume fetching remaining rows using the same connection(which can be confirmed by comparing source port of packets).
3. We dumped the thread at which JDBC hangs at socket read of JDBC driver
By the way, the version of JDBC we use is 11.2.0.1 and JDK version is 1.5.0_22.
The SQL statement is very simple:
select sum(n.netvalue) npvi,
n.HISCENEID hsid,
n.counterpartyid cid,
n.productid pid,
n.opendays
[Code] .....