I'm training myself with the EJB 3 technology. I would like to create a stateless bean that instead of returning a String, it returns an object. I tried in the same way I did with the first exercise, but I'm getting several errors.
View RepliesBelow is my ejb-jar.xml
<!DOCTYPE ejb-jar PUBLIC '-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN' 'http://java.sun.com/dtd/ejb-jar_2_0.dtd'>
<ejb-jar>
<display-name>TestEJB</display-name>
<enterprise-beans>
<session>
<ejb-name>TestSessionLocal</ejb-name>
[code]....
All my classes implement proper local classes EJBLocalHome and EJBLocalObject.This configuration used to work fine in JBOSS 5.1.0 G
I am doing this
@Startup
@Singleton
@ConcurrencyManagement(ConcurrencyManagementType.CONTAINER)
@Lock(LockType.READ)
public class ResourceBean {
[Code] ....
And I call this singleton bean from a stateless session bean like this
@Stateless
public class ClientBean {
@EJB
ResourceBean resource;
public String create(String r)
{
String res=resource.returnString(r);
return res;
}
}
But resource.returnString(r); gives a org.apache.jasper.JasperException: java.lang.NullPointerException I started the glassfish server in debug mode and found out that "resource" was null. but @PostConstruct in singleton does print which means singleton bean exists.
Can we call singleton beans with no interface in such a way form a session bean? I actually want to acquire instance of singleton bean when a client invokes method in Client bean...
I read JEE6 doc and confused with : Does container managed entity manager (injected by PersistenceContext annotation) is thread-safe in stateless session bean in multiple-thread env?
See code below, if there are 2 requests to stateless sesion bean in 2 concurrent threads , is it using same Entity Manager Instance or not?
@Stateless(name = "HRFacade", mappedName = "HR_FACES_EJB_JPA-HRFacade-HRFacade")
public class HRFacadeBean implements HRFacade, HRFacadeLocal {
@Resource
SessionContext sessionContext;
@PersistenceContext(unitName = "HRFacade")
private EntityManager em;
[Code] .....
I run a bash command and save the output as a string object
String str1 = "" +getLastOutput();
str1 would look like this: abcd efgh lkmn xsds
In this string ( str1) i need to check three separate words are there.
If i have an if statement with str1.contains("xyz") && str1.contains("lkmn") &&str1.contains("zzzzzzzzzzzz")
How can i get the one that is not there returned to the screen? so i can use elsewhere?
//Scanner Test
String stream2 = "ab34ef
56";
// create a new scanner with the specified String Object
Scanner scanner = new Scanner(stream1);
// find a string "World"
[Code] ....
Matched expression found by findInLine: 34
ef56
is new line? right?
The java.util.Scanner.nextLine() method advances this scanner past the current line and returns the input that was skipped. This method returns the rest of the current line, excluding any line separator at the end.
then 56 is in new line and it must return ef.What is the problem?
i am trying to write a class method which will take in a string and returns a string which is the reversed version of that string. it compiles fine but when i try to run it it states Main method not found in class StringReverse,please define the main method as public static void main(String[]args). I am new to java and cannot figure out
import javax.swing.JOptionPane;
public class StringReverse {
public String reverseString(String str){
JOptionPane.showInputDialog(null,"Please enter word");
char c = str.charAt(str.length()-1);
if(str.length() == 1) return Character.toString(c);
return c + reverseString(str.substring(0,str.length()-1));}}
I need to create a method that returns a new array containing the componentwise sum of its arguments(if length is the same). For instance, if the input arrays are {0,1, 2} and {2, 2, 3} then the output is {0+2, 1+2, 2+3}, i.e. {2,3,5}.If the input arrays have different numbers of elements, the method should return null.
I came with something like this, however i dont know how to make a copy of an array from two arrays. My code obviously wont compile. package whatever;
import java.util.Arrays;
public class hhhh {
public static void main(String[] args) {
double [] a = {1,2,3};
double [] b = {2,3,4};
[code]...
How bean object have been tagged to JSTL?
View Replies View RelatedSo I'm pretty sure this is correct, as it follows most examples I can find online, but I keep getting an error that my return variable cannot be resolved. The error is on the return conn; statement. It says conn cannot be resolved. If I place it above within the try block it allows it but then I receive an error saying the method getDBConnection must return type Connection.
import java.sql.*;
public Connection getDBConnection() {
try {
Class.forName("org.sqlite.JDBC");
String path = "jdbc:sqlite::resource:project.db";
[Code] .....
I don't want to create this method. Basically I want to connect to the database in the main program, but I do want methods that can access the DB too. But however I place it, it doesn't let me touch any of the DB variables outside of the Try block.
About creating views,
1. When we have a view and this uses two or three managed beans and not only one, is this ok? is a good design?
2 If we have two views and both of them only share one functionality (they need to display datatable with clients) , for the second view and for the shared functionality, should I in the managed bean for the second view create the same method that gets the clients or reuse the method in the managed bean created for the first view?
This is what I have to create : Write a method that returns the largest object in an array of objects. The method signature is:
public static Object max(java.lang.Comparable[] a)
All the objects are instances of the java.lang.Comparable interface. The order of the objects in the array is determined using the compareTo method.
Write a test program in the main method that creates an array of ten Strings, an array of ten Integers, and an array of ten java.util.Dates, and finds the largest string (i.e. in the alphabetical order), Integer, and Date in the arrays.
Name your java class Max and your java file Max.java.
I am struggling a bit with this code as I am sure you can see, and am at loss. I have never used the compareTo method. Am I doing this right, or on the right track with my code?
public class Max implements Comparable {
public static Object max(java.lang.Comparable[] a) {
java.lang.Comparable tempObj = null;
for (int i = 0; i < a.length; i++) {
if (a[i].compareTo(tempObj) > 0)
[Code] ....
So i have used the "remove()" method in conjunction with an iterator to remove an object from a HashSet in my program, and part of my exercise requires me to return said object. What I can do to return an object that has been removed using "remove()" method?
View Replies View RelatedI've been assigned to create a Black Jack game with a gui. In this game I've created a seperate Player and Dealer class, and both initiated them, however when I try to call a Player object in a certain way I get a null pointer reference. (It should be noted that the Player object is an array)
public void runGame(){
while(running){
while(dealer.getPoints() <=19){
int count=0;
[Code] .....
And this is how I've initilized the Player class in the constructor
Player[] players = new Player[numberofplayers];
for(int i=0; i<numberofplayers; i++){
players[i] = new Player(i);
players[i].setDeck(d1);
gui.add(players[i].getPanel());
}
What I don't get is if I change players[i] to dealer, it works fine.
The question pretty much says it all, but I tasked myself with creating a program about lemurs. There are multiple class files in this program. In the below code snippet, I have my TreeLemur.class which extends to the Lemur.class which extends to the Mammal.class. However, when I create a Tree Lemur object in the main program, it is returning null consistently from certain methods. What am I doing wrong here?
TreeLemur.class :
public class TreeLemur extends Lemur {
private String groupSize;
private String diet;
private String fur;
public void setGroupSize() {
groupSize = "
Group Size: Large";
}
[Code]...
As of yet, I'm just trying to get Tree Lemur working properly to continue with creating the other if-branches within the main program.
I have a project I am currently working on using Primefaces and MySQL. I have a page that will display information queried from the database. I have textfields that will display the data from a given record. But I want to ensure that the displayed data cannot be altered. I decided on disabling the textfields unless the create or edit button were clicked. At which point all textfields will be enabled for editing, and cleared if create button was clicked. I want to push the disabling/enabling of the elements back to a managed bean, but I want to have the bean take in two lists or arrays, one containing all elements by ID and one containing a list of exempt elements. Is there a way I can create a List or Array of the ID's that I can send to the bean? I know little in Javascript and previous attempts to implement it have met with little success.
A short example of the code:
<p:tabView>
<p:tab id=pmDBTab title="PM Database Tab">
<p:panelGrid id="projectInfo">
<p:row id="rowOne">
<p:column id="r1c1" colspan="2">
<p:outputLabel id="searchLabel" for="searchField" value="Search: " style="font-weight: bolder"/>
[Code] ....
I want to create a list that would contain all and another that would contain the exemptions such as searchField, searchCriteria, searchButton, projectList and viewButton. The actual exemption list is far smaller than the list of all children. I have found sources that can disable the elements with a java bean, but I have not been able to find one that would allow me to define those that should and should not be disabled, then vice versa for enabling.
I am writing a code where in the first method the question will ask whats your favorite website. for example www.javaprogrammingforums.com...when it outputs it will read just "javaprogrammingforums" without the www. and the .com.
Because the program will ask a series of questions in the main, I would like website question to be returned to the main. Here is my code, and what can I do?
import java.util.Scanner;
public class chapter3 {
public static String website(Scanner kb) {
String website;
System.out.println("What is your favorite website?");
website = kb.next();
[Code] ......
Write a method that accepts an array of Strings and a character c. The method must return the count of all cs in the strings of the array.
Here's what I have written:
[
public int countC(String[] strings, char c) {
int count = 0;
for(int i = 0; i < strings.length; i++) {
for(int j = 0; j < strings[i].length(); j++) {
if(strings[i].charAt(j) == c) {
count++;
}
}
}
return count;
}]
Does this look correct?
I have doubts in string declaration. As I know we can declare string in two ways:
1. String a=new String("Hello");
2. String b="Hello";
What is exact difference between them? Another thing is when I check (a==b) it retuns me false, but when I check a.equals(b) it returns me with true. Why So?
The following alert returns an added string instead of adding the var together to give me a total?
var tvHours = prompt('How many hours of Tv do you watch last week?');
var webHours = prompt('How many hours of internet surfing did you do last week?');
var gameHours = prompt('How many hours of video games did you play last week?');
alert(tvHours + webHours + gameHours);
Also can you store a var in an alert? e.g ( var time = alert(tvHours + webHours + gameHours); ???
public class Lab07 {
public static void main (String[] args) {
System.out.println(convertToInt("123"));
} public static int convertToInt(String str) {
int conversion = 0;
int i;
[Code] ....
The only methods I am aloud to use is length and charAt, which I have done. I see why it is returning a 0 at the end of the value returned, its because I set my int conversion = 0. If I just declare it I get a compiler error that it must be initialized.
I must write a method that accepts a string and returns an int. The method should sum the unicode values of each character, so the string "ABC" should return 198. Also the only string class methods I'm aloud to use are length, charAt, and substring. I just don't know how the get the Unicode value.
View Replies View RelatedI'm trying to get the jsessionid cookie value using the following line in my jsp. It always returns empty string. Is this correct behaviour?
response.encodeURL("")
Task:The main method of the class Things below creates an object called printer deriving from the class PrintingClass and uses that object to print text. Your task is to write the PrintingClass class.
Program to complete:
import java.util.Scanner;
public class Things {
public static void main(String args[]) {
String characterString;
Scanner reader = new Scanner(System.in);
PrintingClass printer = new PrintingClass();
System.out.print("Type in the character string for printing: ");
characterString = reader.nextLine();
printer.Print(characterString);
}
}
// Write the missing class here
Note: In this exercise the solution is part of a conversion unit where many classes have been declared. Because of this the classes are not declared as public using the public attribute.
Example output
Type in the character string for printing: John Doe
John Doe
My Class:
class PrintingClass {
public void print(){
System.out.println(characterString);
}
}
I'm new to JSP but I've to use it to grab data coming from an external site, pass data to a Bean, write data in a DB and redirect the user to another page. Follow the JSP page.
<%@page import="EJB.getResponse"%>
<%
long paymentID = Long.parseLong(request.getParameter("paymentid"));
String responsecode = "9999";
getResponse g = new getResponse();
[Code] ....
This is the bean:
@ManagedBean
@RequestScoped
public class getResponse implements Serializable {
private Long paymentId;
private String result;
private String auth;
[Code] ....
On the console I see the prints but I receive the NullPointerException
WARNING: StandardWrapperValve[jsp]: PWC1406: Servlet.service() for servlet jsp threw exception
java.lang.NullPointerException
at EJB.getResponse.printData(getResponse.java:72)
at org.apache.jsp.notify_jsp._jspService(notify_jsp.java from :60)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:111)
[Code] ....
Which method is used while passing or returning a java object from the native method?
View Replies View Related