Servlets :: Submission Parameter Order Maintained?
Nov 27, 2014
Is there anything in the HTML specification about whether submitted GET or POST parameters must retain their order? E.g. In the following is there anything in the spec that says the following data should be returned in the order they appear in the HTML code. And, most importantly, is there anything that says the firstName and surname fields should actually match up with each other, i.e. the order can change but in the same way for each field?
I would like getting a specific parameter name from the set of request parameters. In particular the name of the 4th parameter in the request parameter set.
I was wondering if there is a way to be certain that listeners would be invoked in any specific order? Note that I am referring to servlet specification version prior to version 3.0. As per version 3.0, the ordering followed would be the one in web.xml (Reference: Servlet specification 3.0: Section 8.2.3). This section also says that prior to 3.0 the order of invocation is random.
Possible duplicate entry but reply does not match the specification text : URL...
In one jsp page, I submit a form with a message body with following html code (which is store in "MsgBody" in my request)
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta content="text/html; charset=utf-8" http-equiv="Content-Type" />
[code]....
But when I submit my form, I received in my servlet a parameter "MsgBody" without several tag like <html>/<body> ... do you know this behavior, by default tag are delete ?
How is session maintained in the application server, internally what happens when the user has logged in ? We create a session and store the user details which will be stored in the session object in the server with a unique sessionID which will be validated when the same user login the system again? But how exactly the session is maintained in the Server internally?
Why we need to use ServletContext attribute when we already have ServletContext parameters.Whats the difference between ServletContext Attributes and ServletContext parameters.
I am showing a jsp page asking user to select a course from dropdown <select> options fetched from database.When user selects a value and click on submit button , I want to show the details of the course on the same page .how can I get the value of user selection on the same jsp page.Then I can make a query using that value and show other details on the same page.
Click the title of the assignment to see Due Date and submission features.
Write a program that determines the number of Dots in an input line. Read in the line into a string. Next use the charAt( ) method in a loop to access the characters one by one.
Your program should have comments towards the top of the program. Copy at least two sample runs and paste as a comment at the bottom of the program. At least one sample run would be a string that has a few blanks. At least one sample run would be a string that does not have any blanks.
Use Assign5_{your last name} as the name of the program.
Submit one file, the Java file only.
As a general rule; no credit is given to work submitted late. If any consideration is given for partial credit; such decision will be made at the end of the semester; at the point in time when the Course Letter grade is determined.
I have a library that uses a ThreadPoolExecutor, backed by a bounded queue.
We submit a large number of tasks to this executor, constantly polling an external dependency for new work. However, this executor has a fixed size. When a ThreadPoolExecutor is busy, it queues up to the blocking queue's capacity tasks in its blocking queue, at which point it starts rejecting tasks.
What I'd rather do, instead of requesting more work, and then throwing it out, is to detect that we're totally busy and stop requesting work until a thread frees up.
Now, I know that one approach is to rewrite the workers such that they are infinite loops, who poll for work when they're finished. Due to the large number of consumers of this library, this is not an option.
I have come up with two other solutions.
1) This is one that I know will work, which is to use a semaphore or other concurrent counter to track how many tasks I have submitted, and stop requesting more work when that semaphore is out of permits. The processors release a permit when they complete (whether due to exception or success).
2) The other option, since I know this is a ThreadPoolExecutor, is way simpler, but also is something I'm not sure is reliable.
I can compare executor.getActiveThreads() + executor.getQueue.size() to the maximum number we can handle before rejecting (maxThreads + queueSize). This change is far simpler, but I'm not sure if those calls are a reliable way of counting the current work.
One of the random number generators in Java extract the higher-order bits of the random number in order to get a longer period.
I'm not sure if I understand how this is done. Suppose that the random number r = 0000 1100 1000 1101. If we extract the 16 most significant bits from r; is the new number r = 0000 1100 or r = 0000 1100 0000 0000?
I have a button in jsp, when the onclick event is fired, it will send the request to someaction.do to generate a report and display that report in a new window.
After clicking the button to generate the report, in the business class a sql query is getting executed.
If the query result has less data, then I don't have any problem, I could view my report page.
If the query result has more data, then the query takes at least 5-6mins to complete. However, before the query completes its execution, the same request is automatically invoked again. Due to this the report is not getting generated because [...of the multiple requests?], the browser shows an Internet Explorer error and ends up at a blank page.
No exception is thrown and the only place I could find the place of query execution it stops and starts as a new request from web.xml with Servlet Filters, Action.
Note: For a single .do request, the request is getting repeated for 3 times. Overlapping of request also takes place.
I was practicing my java skills and came across an exercise in which a non parameter constructor calls a two parameter constructor. I tried a few searches online but they all came back unsuccessful. This is the part I am working on:
public PairOfDice(int val1, int val2) { // Constructor. Creates a pair of dice that // are initially showing the values val1 and val2. die1 = val1; // Assign specified values die2 = val2; // to the instance variables. } public PairOfDice() { // Constructor that calls two parameter constructor }
I tried calling the two constructor using the line "this(val1, val2)" but I get an error because val1 and val2 are local variables.
Then I tried to use the same signature: "this(int val1, int val2)" but that didn't work either.
I'm displaying a 3-column table with the column names ID, name, and salary. I made the ID into a link to go to the EditServlet class. What I'm trying to do is figure out which ID# was clicked to get onto the servlet page, how to implement that dynamically?
I know that if you put something like ?x=1 and then getParameter("x") on the servlet page would work, but then all the IDs would have the same parameters since I'm using a for loop to print out my ArrayList of objects.
I'm using Java in BlueJ where I'm trying to write a class to store cycling club membership details in a map. I'm trying to pass a map as a parameter to a function that will iterate over the map and print out the member details. My code is:
public class CtcMembers { //instance variables private Map<String, Set<String>> memberMap; /** * Constructor for objects of class CtcMembers
[Code] ....
When I execute the following in the OU workspace:
CtcMembers c = new CtcMembers(); c.addCyclists();
I can see a map populated with the expected details.
When I execute the following in the OU workspace:
c.printMap(c.getMap());
I get the following error:
java.lang.ClassCastException: java.util.HashSet cannot be cast to java.lang.String in CtcMembers.printMap(CtcMembers.java:81) in (OUWorkspace:1)
I wasn't aware I was trying to cast anything so this has got me baffled.
I am trying to create a method called getVariable will has a parameter of a variable that has a type of Test, an enumeration. An int variable called x is assigned a value of 5, and through control statements, I want its value to change depending on what the argument is. I was able to correctly create this method, but when I use it I get an error saying, "non static method getVariable(Test) cannot be referenced from a static context" on line 28.
Here is the code:
package javaapplication5; public class Product implements Cloneable {
I am taking a parameter of type String and checking if either the city or state contains the "keyword", whatever it may be. I am using an arrayList of 10,000 customers and adding any customer that lives in a city or state that contains the keyword to a new arrayList and then returning that arrayList. I thought my solution was correct, but when using the JUnitTest provided, it is not quite passing the test. My solution is as follows.
Java Code:
public ArrayList <Customer> getMailingList(String keyword){ ArrayList <Customer> key = new ArrayList<Customer>(); keyword = keyword.toLowerCase(); for(Customer c : data){ if(c.getState().contains(keyword) || c.getCity().contains(keyword)){ key.add(c); } } return key; } mh_sh_highlight_all('java');
import acm.program.*; import java.io.*; import java.io.PrintWriter.*; import acm.util.*; import javax.swing.*; public class PrintWriter extends ConsoleProgram {
public void run() {
try { PrintWriter wr = new PrintWriter( new FileWriter ("hello.txt") ) ; wr.println("Hello world!"); wr.close(); } catch (IOException er) { println("File could not be saved."); } } }
(I added the imports at top myself.) However, I am getting compiler errors for the lines: PrintWriter wr = new PrintWriter( new FileWriter ("hello.txt") ) , which says that the constructor PrintWriter( FileWriter ) is undefined, and wr.close();, which says close() method is undefined.
Pretty sure the only real problem is that PrintWriter is not accepting the FileWriter as constructor, but I don't see why. I have tried this on machine with JRE 1.4 and it worked as expected, creating new file titled "hello.txt", prints line of "Hello world!" in that file, and saves it to the directory I picked in the dialog. But I can't get it to work on this machine that uses Compiler 1.6, Java Runtime v8u25.
I have also tried using just a string in the parameter for PrintWriter, such as PrintWriter wr = new PrintWriter ("hello.txt") , and from what I can tell by reading the java spec for java 8, this should work. [URL] .... But I get error message for that constructor as well.
So method invia call the method popolaScompiute, inside popolaScompiute there is an iteration through some id and for some id can occur an error; what i want is the getting the value of id in the first method invia, using the block try/catch. Is there a way to accomplish this?
I have a variable <c:set var="var1" value = "myvalue" /> , I want to pass var1 as <%= new customclass().method1(var1) %>.what is the syntax to pass this value.
