Servlets :: Why Query String Is Not Getting Created In DoPost Method
Dec 9, 2014Why query string is not getting created in doPost method of HttpServlet?Is this reason is enough - it is supplying data in html body.
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Servlets :: How To Change URL To JSP Name After Passing To DoPost Method
Aug 12, 2014I have a log in page accessed by: localhost/Security/Login.jsp
When I click a log in button, doPost() method is executed from Login.java and displays the contents from main.jsp.
However,its url on my browser is localhost/Security/Login.
Generally, the pattern is the address of Login servlet.
So if I click a button from main.jsp, error occurs because it is trying to locate a servlet from /Security/[Servlet name].
What I want is to change the url as I go to main.jsp to localhost/Home/main.jsp.
Is this possible?
How Many Objects Created With New String Method
May 22, 2014I am little confused about String creation in java.
Doubt 1: How String objects assigned to Pool area:
1. String s="in pool";
2. String s1= new String("not in pool");
How many objects created in statement 1 and 2. According to recent discussion with my colleague, one object created in String pool in case 1. And in case 2, two objects are created, one as literal goes to String pool and other with new() opr goes to Heap.
If above is correct, Ain't we wasting double memory for same object ? Really need clear understanding on this
Doubt 2: How does intern() work: Please see if my below explanation is correct
1. If String literal is already present in String pool , and i create a same string with new operator, reference to object is changed to pool area.
2. If String object is created using new operator and intern is called on it. If same string object is not present in the String Pool, Its moved to String pool and reference to this in Pool is returned.
JSP :: Translation Into Servlet DoGet / DoPost Method
Feb 26, 2014I have the below piece of code in my jsp page.
<% double randomNum= Math.random(); %>
<%= randomNum%>
Now I am trying to run this jsp, it will be translated into servlet. When i checked the generated servlet I found both the above code snippet(scriplet and expression) came in to _jspService method. But in the internet and in many other book i found that scriplet and expression portions will come in the doGet/doPost method (which will be called from jspservice).
So any specific reason why in this case it went in to jspservice method (though I am getting desired output)? I am using tomcat 6.
Servlets :: Pagination Of Oracle Database Query Result
Jan 6, 2015My query retrieves more than 5000 records from Oracle database. I want to display the records 100 per page. I know it is called pagination. Any detailed styp-by-guide or tutorial or example available?
View Replies View RelatedJSP :: Query String URL
Apr 10, 2014how this query string will be prnted it is not showing me the psid values.
<tr bgcolor="pink" >
<td><%=resultSet.getString("FirstName") %></td>
<td><%=resultSet.getString("LastName") %></td>
<td><%=resultSet.getString("Username") %></td>
<td><%=resultSet.getString("Password") %></td>
<td><%=resultSet.getInt("Psid")%></td>
<td><a href="Edit.jsp?psid="<%=resultSet.getInt("Psid")%>>Edit</a></td>
<td><a href="Delete.jsp">Delete</a></td>
</tr>
Servlets :: When HTTP Session Object Created In Web Application
Jul 17, 2014When does HTTP Session object is created in web application. Suppose I have a website. Home page of website is HTTP page which contains details of company and link to Login page.
Consider below mentioned user journey as scenario:
a. user arrives at home page of website
b. user click on Login page
c. user fill in login details on login page and click on Submit
d. user is successfully authenticated and authorized from back end
e. User specific page is shown
f. user click on logout link
g. user is successfully logged out from website
h. user is redirected to home page
i. user closes browser
In the above mentioned user journey,
a. at which step does HTTP session starts (means at which steps does HTTP Session object is created ? )
b. at which step does HTTP session ends ?
In case required, assume tech stack to be Java 7, Servlet 2.5, JSP, Tomcat 7, Apache web server (for static web contents).....
Query About Use Of NextLine Method Of Scanner Class
Apr 10, 2014My code is as follows:
import java.util.Scanner;
public class GetUserInput {
public static void main (String args[]) {
int i;
float f ;
String s;
[code]....
My Query is: input.nextLine() does not wait for user input. Instead it continues execution from next line. But if I move up input.nextLine(); before both input.nextInt(); and input.nextFloat() in the above code, the execution works fine, input.nextLine(); waits for user input. edited code and output are as follows.
import java.util.Scanner;
public class GetUserInput {
public static void main (String args[]) {
int i;
float f ;
String s;
[code]....
String Value To Be Name Of Variables Created
Mar 11, 2015Is it possible to have the value of an entered String to be set as the name of the String to be created whilst running.For example: String username= Keyboard.readString() & the user entered for example the word: "Hello".Is there a way how I can make the Java Program create another String named Hello (Inputted value of String username).
If this is allowed, what do I have to use and if possible show me exactly what I have to do with the example mentioned above?
How Many String Objects Are Created In Each Line
Aug 15, 2014how many objects got created at each line (in String pool or in Objects memory):
public class Test {
public static void main(String[] args) {
String s1 = "test";
String s2 = new("test");
String s3 = s1 + s2;
StringBuider sb = new StringBuilder().append(s2);
}
}
Passing Object Created In One Method To Another?
Oct 29, 2014I am working on an independent project it is a simple little text based rpg that will run in a counsel window. I have an object for Character that is creating during a CreateCharacter method. I want the play to be able to enter a character that will open up a menu that displays things like the name and health and stuff of the character from the object created in CreateCharacter, but because I have it in a different class I don't know how to reference the object made in CreateCharacter.
I have it in 6 files
Character --- Object with getters/setters for things like name, age, race, class, ect
MainMenu --- Displays title and promts for new game and quit
CreateCharacter --- Walks through and sets all values in Character
Stats --- Keeps the players stats (health, attack, ect) in an array
Intro --- Beginning demo thing (not really important for this question)
Menu --- Displays all current user stats (Having issues with this one)
Example I have this in Menu
System.out.println("Name: " + ????.getName());
PreparedStatement For MySQL Query - Where Query Seems To Get Cut Off
Mar 21, 2014I am having a problem with a PreparedStatement for a MySQL query, where the query seems to get cut off. I can't really post a self contained example, because it involves an SQL database.The part of the code with the problem...
Java Code:
public void insertEntry(
Hashtable<String, String> strings,
Hashtable<String, Integer> integers,
Date created, Date paid, boolean enabled)
throws ClassNotFoundException, SQLException {
Class.forName("com.mysql.jdbc.Driver");
[code]....
The output of the whole program, though all it has done so far is create some default values and attempt to insert them with the above code, where the problem occurs.
Debug: SQLpaid = 1990-03-21
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorEx ception: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'INSERT enabled=0, username='default_username', created='2000-03-21', paid='1990-' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInsta nce0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInsta nce(NativeConstructorAccessorImpl.java:57)
at sun.reflect.DelegatingConstructorAccessorImpl.newI nstance(DelegatingConstructorAccessorImpl.java:45)
[code]....
Method Creation - Take A String With Duplicate Letters And Return Same String Without Duplicates
Nov 7, 2014How can I write a method that takes a string with duplicates letters and returns the same string which does not contain duplicates. For example, if you pass it radar, it will return rad. Also i would like to know how can I Write a method that takes as parameters the secret word and the good guesses and returns a string that is the secretword but has dashes in the places where the player has not yet guessed that letter. For example, if the secret word is radar and the player has already guessed the good guesses letters r and d, the method will return r-d-r.
View Replies View RelatedString Split Method To Tokenize String Of Characters Inputted?
Sep 27, 2014I am currently trying to make a calculator in Java. I want to use the String split method to tokenize the string of characters inputted. I thought I was using the String split method wrongly, because I had surrounded the characters I wanted to delimit with square brackets. However, when I removed the square brackets, the code threw an exception when I pressed the equal button. The exception was a PatternSyntaxException exception. Am I using the String split method wrongly? And why is the exception thrown? Here is my code:
import javax.swing.*;//import the packages needed for gui
import java.awt.*;
import java.awt.event.*;
import java.util.Arrays;
import java.util.List;
import static java.lang.Math.*;
public class CalculatorCopy {
public static void main(String[] args) {
[Code] .....
Class Method Which Take String And Returns A String In Reversed Version
Dec 16, 2014i 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));}}
JSP :: Forward Invokes DoPost When Manual Link Invokes DoGet
Aug 17, 2014I have a jsp page that has a url that looks like this
<p><a href="SubscriptionController?action=subscriptionlist">Administrator Subscription Maintenance List</a></p>
Now I want to essentially slide through that page by using jsp:forward instead of the link
<jsp:forward page="/SubscriptionController?action=subscriptionlist" />
Problem is, the link invokes the doGet method of my servlet and the jsp:forward invokes the doPost. Is it possible to use jsp:forward and specify doGet somehow?
Accepting String And String Array In Just ONE Method?
Mar 18, 2014Code a Java method that accepts a String array and a String. The method should return true if the string can be found as an element of the array and false otherwise. Test your method by calling it from the main method which supplies its two parameters (no user input required). Use an array initialiser list to initialise the array you pass. Test thoroughly.
public class test {
public static void main(String[] args) {
Printhelloworld();
String[] verbs = {"go", "do", "some", "homework"};
printArrays(verbs);
[Code] .....
String Split Method To String Array
Sep 21, 2014So I'm creating a class which when given three inputs uses them as sides of a triangle and tells ther user what type of triangle it is, or if the input is invalid, tells them why it is invalid. I'm readin the input as a string and then trying to split it into a string array, from there checking to see if it has 3 elements.. in which the data is good at that point, and then converting them to ints and checking to see if they're negative ansd finally checking to see if they can work as sides of a triangle ie a+b >c, a+c >b , b+c >a.
I'm trying to split it into an array of strings but am getting an error, and can't seem to figure out why as this should be working from what I've read of the string.split method online.
import java.util.*;
public class TriangleTest{
private int sideA;
private int sideB;
private int sideC;
public static void main(String[] args){
TriangleTest triangle = new TriangleTest("3 4 5");
[Code] ....
The output reads [Ljava.lang.String;@15db9742
Servlets :: How To Call HEAD Method
Sep 3, 2003I want to call the HEAD method on a servlet.If in my HTML code, I specify -
<form name="testHead" action="/servlet/servletName" method="HEAD">
And the servlet handles the HEAD method in the sense that the doGet() method returns if the method type is HEAD.When I run it, the servlet returns the code returned by the entire doGet() method. This shows that the doGet() method does not realize that it is a HEAD method and it should return back without processing further.The application server is Tomcat 4.0.
Servlets :: Why Session Not Type Casting Into String
Oct 17, 2014why my session not type casting into String? I'm placing that code below where problem arised.
HttpSession hs1=request.getSession(false);
out.println("hi");
String t1=(String)hs1.getAttribute("name");
out.println("hi "+t1);
in my above code first "hi" is printed successfully but next statement arises type cast exception.
Servlets :: Getting HTML In String When Hit JSP - Download Data In PDF File
Aug 15, 2014I need to get the html in string when i hit the hit the jsp in servlets basically i need to put the output of jsp in pdf file when i hit one link i need to download that data in pdf file. I am using itextpdf.
Sample code
pResponse.setContentType("application/pdf");
((HttpServletResponse) pResponse).setHeader("Content-Disposition", "attachment; filename=report.pdf");
//Get the output stream for writing PDF object
OutputStream outStream=pResponse.getOutputStream();
ByteArrayOutputStream baosPDF = new ByteArrayOutputStream();
[Code] ....
I need to convert the sample download.jsp to html so that i can parse
// XMLWorkerHelper.getInstance().parseXHtml(docWriter, document,new FileInputStream(jspPath),new FileInputStream(csspath) ,null ,new XMLWorkerFontProvider());
Servlets :: JSessionID Cookie Value - It Always Returns Empty String
Feb 6, 2014I'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("")
Servlets :: Call Constructor / Method Upon Redirecting To Another Page?
Aug 13, 2014I have login.jsp and home.jsp.
Each have its own servlets.
When I click Login button from login.jsp, it will navigate to home.jsp.
But before displaying home.jsp from he user, I want to call homeServlet.java's constructor/method.
This is because I want to populate a dropdown from home.jsp from a database.
I'm using MVC2 Servlet/JSP/Bean framework and AMAP, I do not want to execute javascripts/jquery for populating dropdowns.
Java Servlet :: Two Servlets Communication With Post Method
Feb 22, 2013We have two servlets application running on same server with Java EE 6 with below mention application URL.
Servlet1 Application URL: http://<severname>/*servlet1*
Servlet2 Application URL: http://<severname>/*servlet2*
My question is how to call Servlet2 from Servlet1 with Post method without using server name. May be something like this:
servlet.invoke(servlet2).
Servlets :: Some Methods Such As ServletRequest GetParameterValues Return A String Array
Jan 5, 2015Some methods such as ServletRequest's getParameterValues return a String array whereas others (e.g. HttpServletRequest's getHeaders) return an Enumeration. Do these return types need to be learned parrot-fashion, or is there some sort of logic to it?
View Replies View RelatedServlets :: How To Implement A Callback Method For A Post Async Task
Mar 26, 2015I am developing an app with a Java Servlet backend, and I am trying to get the Async call (AsyncTask - Android Developers) to get my response message Synced with the rest of the client and being able use this information wherever I want. Without a callback method, when from the caller class I use the commands:
ServletPostAsyncTask s = new ServletPostAsyncTask();
s.execute(new Pair<Context, String>(ListViewPrenota.this, "tours"));
Tours ttours = s.tours;
Tour tour = ttours.getTours().get(0);
I receive a NullPointerException pointing to the third line Tours ttours = s.tours;, since the s.execute() method doesn't wait for the rest of the lines to get executed.To solve this I thought about implementing a callback method with interfaces in Java, but I am not sure on how to do it. For example, what class does have to implement the interface, the ServletPostAsyncTask or the caller class?