I'm trying to share an hashmap(or any other stuff to share data) between a java class and a servlet. The hashmap has to be filled into the servlet with some data and then I have to get those data from the java class.
What is the best approach? I cannot use a DTO because I have several concurrent requests to my servlet.
I'm creating a web applicaion. for that i want to create a registration page. and this registration details have to be stored in the database.
I'm getting the below error while trying to send the data ...
The requested resource (/cmd/InsertRegtodb) is not available.
Here cmd is project name and InsertRegtodb is servlet name.
Actually the servlet is present is the mentioned address. but it is not connecting to it
There is one more servlet in the same folder and which is accessible from another jsp. But this servlet is not accessible even though i have used same code as it is used for the servlet which worked for me previously...
If I want to load data in excel file into table. what is the best way to do it?
View Replies View RelatedIs it possible to get data directly from request object in service method of servlet than why it is not possible to write directly into response object through service method instead of this we have to take PrintWriter or ServletOutputStream class object....
View Replies View RelatedI am a beginner want to compile servlet with following path
javac -classpath Program FilesApache Software FoundationTomcat 5.5commonlibservlet-api.jar;classes:.-d classes srccomexamplewebBeerSelect.java
Problem arises as follows:
javac: invalid flag: FilesApache
Usage: javac <options> <source files>
use -help for a list of possible options
I am trying to create a second class in a single java file (first time trying this) and want to use data from the first class in the second class but I am not able to do it. What am I missing :
package simplecommissioncalculation;
import java.util.Scanner; // import java.util.Scanner
public class SimpleCommissionCalculation {
public static void main(String[] args) {
[Code] .....
I'm trying to insert data into an excel sheet with the below Servlet.
/*
* To change this license header, choose License Headers in Project Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
import java.beans.Statement;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
[Code] ....
But it is giving me the below Exception and stacktrace
java.text.ParseException: Unparseable date: "2-Apr"
at java.text.DateFormat.parse(DateFormat.java:357)
at Serv1.doPost(Serv1.java:53)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:644)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
[Code] ....
i found that the problem is within the date field(, if the problem is with the date, how i can fix it and where am i going wrong.
i'm using eclipse Kepler to create J2EE project.i created student class which return list of information. how to access list in JSP page??
View Replies View RelatedYour Tester class main method must use an array or an ArrayList of Person objects. It must be populated from a text data file, friends_data.txt. Add the following data to your text file,
Michelle, 12/20/2008, Camilla
Bryan, 3/8/2007, Tom
Camilla, 6/7/2005, Michelle
Tom, 10/15/2007, Bryan
Charlotte, 3/2/2008, Michelle
Each line has the meaning:
-Person name, Person date of birth (MM/DD/YYYY), name of best friend
-Write a Java program that reads in the data from the friends_data.txt file, allocates a new
-Person for each and then stores the newly created object in either an Array or an ArrayList.
-Next print out a report showing the following information for each Person,
1. The Person's name
2. Their popularity counter
3. Their age on May 1, 2014
4. The name of their best friend
5. The age of their best friend on May 1, 2014
Finally, print the name of the most popular Person and the name of the oldest Person.
Person Class
import java.util.ArrayList;
public class Person {
public String personsName;
public String personsFriend;
public String personsBirthday;
public int personsPopularity;
public int popularity = 0;
[code]...
I keep getting this error from the compiler:
System.out.println("Popularity : " + personsOfInterest[i].getPopularityNumber());
"method getPopularityNumber in class Person cannot be applied to given type:
Required: java.lang.String[]; found: no arguments; reason: actual and formal argument lists differ in length.
I can understand basic concepts such as OOP, Threads, Events and GUI, I've coded a little but I've always had this bothering me:
Explaining by example:
public class X{
int x;
String y;
public static void main(String[] args){
x = 10;
y = "hello ";
[Code] ....
Okay, i'm pretty certain that code won't work, but I just want to show you conceptually, not actually care whether the code works or not. In case I wanted to get that code to work I should have probably used a Swing application to get a KeyListener in the first place, but I guess I know that, and if this was working, what would happen theoretically is, the code would run, initialize x to 10, and y to hello, then when a key is pressed, it will update x to 11 and y to hello world, I'm pretty sure that's what happens.
In this case, I used a inner class to update it's parent's members, I've seen this done before and I can vouch for the fact that it's a legitimate way to code a class.
Now in this example:
class X{
int x;
String y;
public int getX(){ return x; }
public String getY(){ return y; }
[Code] ....
So in this overly complicated example, i'm trying to share class X with both class Y and class Z, just that how to share the members of class X with the different classes without making a new instance of X. In the previous example, I could access the parent's members because the inner class was implicitly capable of accessing the parent's members. However in this case, If "Y" starts an instance of X, then how do I access it? because it's a side by side class not a hierarchy for me to access the parent's members.
I have a situation to load data while JSF page loads. Also have a filter which populates user information from http request.
I was expecting the filter first to populate the user information and in the managed bean get method to verify the user information and get the data (from database). But in this case i see the managed bean get method is invoked before filter populates user information and i get null pointer exception because the user information is null.
I had to work around to get the user information from FacesContext in the managed bean get method because the user information wasn't available. Is there a way to make sure the filter is invoked first?
**Getting data on from rfid scanner as Serial rs232 port in JFrame**, in this case I have made a JFrame form and I have a JTextField for storing data rfid as a String. Actually, I found a class from internet that read the RFID reader as byte, now How To get data from my RFID Class to my JTextfield Jframe in my main class as String?
Here my RFID class :
package view;
import java.util.*;
import java.io.*;
import javax.comm.*;
public class ListPorts implements Runnable, SerialPortEventListener {
static CommPortIdentifier portId;
static Enumeration portList;
[Code] ....
Is it possible that my RFID class merge with my Main class ?
How to get a double data type in order to display in the view through a servlet:
objReferencias.setImprevistos(request.("imprevistos"));
Question:
request.getDouble("imprevistos));? or
request.getDoubleParameter("imprevistos));?
I've been searching but I have not found the appropriate answer.
I have a string of variable tags (tag) filled with variables, and using a Scanner (scan) to manipulate and generate data dictionary add cards for each. The variables are delimited with new line character, and the variables are structured such that the actual name of the variable contains info as to its data type, size, etc. What I need to do is move the scanner to a particular point into the string then use .nextInt() or similar. I don't want to do this to the whole variable, just where I start it from. How can I do this?
E.g..
/* variables in String tag...
ANS_s20Tx12VDstr
ANS_:Tx67MSvis
ANS_zRx11MSctr
...
..
*/
Scanner scan = new Scanner( tag );
int ptr = tag.indexOf( "_" );
ptr++;
if ( Character.toLowerCase( tag.charAt( ptr ) ) == 's' )
// then start at the "_" character and grab the nextInt()
I am new to java. I have recently learned JDBC connection pool in tomcat. To make code reuse I want to share the connection among all servlets without any conflict.
Here My code snippet:
public class GetConnection{
private DataSource ds;
public Connection getConnection(){
try {
InitialContext initialContext = new InitialContext();
Context context = (Context) initialContext.lookup("java:comp/env");
ds = (DataSource) context.lookup("connpool");
[Code] .....
Is this right way to do. Or I will get any problem due to concurrent threads.
Here is my code. Obviously this doesn't do a lot but that's only because I abstracted out the problem so there are not many lines to decipher.
Java Code:
import java.util.Scanner;
class threadOne extends threadTwo {
public static void main(String[] args) {
threadTwo threadTwoObj = new threadTwo();
threadTwoObj.start();
while (!userInput.equals("exit")) {
[Code] ....
What its supposed to do: When the user returns "exit" in the console it is supposed to break out of both while loops in both threads.
What it actually does: breaks out of the while loop in threadOne and not in threadTwo.
Basically the idea is to have a thread running doing computation and another thread able to query it for updates or interact to make changes to the flow. This will be useful, among other ways, for the sorts of problems where finding a solution is easy but where a better solution can always be found with more time. So for example finding directions on a map. Its easy to find a solution, but if you search longer you can find a faster route, if you search longer still than faster still.
Modify the program in Assign4 to synchronize access to the instance variable, balance. Save the program as SyncBank.java. Because balance is a double and not an object, it cannot be used as the monitor. Use synchronized methods or synchronized blocks of code as appropriate. Simultaneously test two threads as was done in Assign4. Because the threads can complete too quickly to determine if they are interfering with each other, delay the adding of a deposit by inserting the following code within the synchronized block or method:
try {
Thread.currentThread().sleep(10000); //sleep for milliseconds
}
catch(InterruptedException e) {
}
My code attempt so far:
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.net.*;
import java.text.DecimalFormat;
public class SyncBank extends HttpServlet //throws ServletException, IOException
[Code] .....
I am absolutely new to Java. I am creating a Servlet and getting the error interface is expected here.
I am using IntelliJ 14.
My Servlet code is as follows:-
package ERPdetector;
import javax.servlet.http.*;
import javax.servlet.*;
import java.io.*;
public class ErpServlet implements HttpServlet {
[Code] ....
Using Eclipse I have imported a WAR with source. I have exported that project as a new war and it ran fine. I then added my own package and exported the war again. The jar file does not show up in /WEB-INF/lib folder. When I deploy the war on a tomcat server it barfs the following error:
Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.sharpline.fields.form.fields.TextAreaFormType] for bean with name 'com.sharpline.fields.form.fields.TextAreaFormType#53c37' defined in ServletContext resource [WEB-INF/activiti-standalone-context.xml]; nested exception is java.lang.ClassNotFoundException:
[Code] .....
It looks to me like my class (jar) is missing in the final war. How do I resolve this?
Actually I am working on java ee6 web application i tried to set value and max age for the cookie...but I was unable to set maxage what ever the max age value i give .it shows as -1.but my browser accepts and stores cookie.
<i>
"
Cookie sa=new Cookie("ssample", "welcome");
sa.setMaxAge(120);
response.addCookie(sa);
"</i>
using HttpServlet methods. What I want to do is to delay an HttpServletResponse. I set up some response.setHeader but then I want to wait a while after setting other values as the length of data to send and the content itself.
I tried to do that in 2 ways:
1. by using Thread.sleep() - in this case even with sleep of 100 ms the response seems to be lost.
2. by response.wait(TIME) - in this case it will never reach the block after wait, whatever TIME value I use.
on my computer, i have configured the environment variables as
CATALINA_HOME : D:apache-tomcat-8.0.9-windows-x64apache-tomcat-8.0.9;
CLASSPATH : D:apache-tomcat-8.0.9-windows-x64apache-tomcat-8.0.9libservlet-api.jar;D:apache-tomcat-8.0.9-windows-x64apache-tomcat-8.0.9libjsp-api.jar;.;
JAVA_HOME : C:Program FilesJavajdk1.8.0_05
path : D:apache-tomcat-8.0.9-windows-x64apache-tomcat-8.0.9in
In reference to the book "Head First Servlets and JSP, 2nd edition", chapter-3(), page-81, the command to compile the servlet file to the desired location is
javac -classpath UsersertApplications2 omcatcommonlibservlet-api.jar:classes:. -d classes src/com/example/web/BeerSelect.java (from the Myprojects/beer-V1 directory)
Whereas I have written
javac -classpath D:apache-tomcat-8.0.9-windows-x64apache-tomcat-8.0.9libservlet-api.jar;classes;. -d classes src/com/example/web/BeerSelect.java
(from the same directory as can be confirmed from the attachment of screenshot of error). this code is in accordance to the location of the respective files in my system, in particular the servlet-api.jar file.
After doing this, my computer is showing the error : file not found.
How do I resolve this? Actually, I don't understand completely what this code is trying to accomplish.
I need to download large amount files, what should I care, Is the following code have problem on download large files
private static byte[] load(String filename) throws IOException {
FileInputStream fis = new FileInputStream(filename);
byte[] data = new byte[fis.available()];
fis.read(data);
fis.close();
return data;
}
I have been trying to find all day long a way to secure my .ear file from modifications made by third parties... My product is packaged as an .ear file which i send for deployment to other administrators. What i am looking for is a way to "sign" my version of .ear versus the deployed version of .ear to be sure that no modification has been made to my code...
View Replies View RelatedI am working on netbeans IDE , but I understand how the application know the parametres for the connections. I understand what is a Context , specifically i understand this code about the init method
Context initCtx = new InitialContext();
Context envCtx = (Context) initCtx.lookup("java:comp/env");
servicioConexiones = (DataSource) envCtx.lookup("jdbc/bd_tutorias");
I want to know how the application knows to use these connection parameters, on the Context.xml
<?xml version="1.0" encoding="UTF-8"?>
<Context antiJARLocking="true" path="/tutorias_pag480">
<Resource auth="Container" driverClassName="com.mysql.jdbc.Driver"
maxActive="8" maxIdle="4" name="jdbc/bd_tutorias" password="mysqladmin"
type="javax.sql.DataSource" removeAbandoned="true"
url="jdbc:mysql://localhost:3306/bd_tutorias" username="root"/>
</Context>
I have a servlet that is called from an web application and creates a Session. The sessionId of this session is passed to a swing application using the approach below:
Re: Trasnferring data from a JNLP call to swing dynamically
From my swing application I want to connect to the same servlet passing the sessionid. The purpose is to work with the same session created before.
It's not working. I'm calling the servlet from the swing application using [URL] ....
Is it possible ?