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.
I have used jsp's to passing request to the servlet or controllers. but we can also pass request from javascript using ajax and sending data using json.
what is the good approach and why? or does it depends on the situations? is yes, what kind of situations?
I am trying to display rows from my database from servlet by passing it to a JSP, but nothing is displayed. I checked the syntax and even the source of the page shows that it gets the data but the rows are not displayed!
public Polygon polygonFrom(Point[] corners) { // method body goes here }
So from what I understand this is a constructor method for a Polygon object from the Polygon class. What I dont get is the name of the method polygonFrom()
Shouldn't a constructor for a Polygon just have the same name as the class? Because from earlier examples in the tutorial it seems to me that this is what has been done
For example:
public Bicycle(int startCadence, int startSpeed, int startGear) { gear = startGear; cadence = startCadence; speed = startSpeed; }
Java SE Runtime Environment build 1.8.0..This is part of the code:
public static int addAddress (String[] number, boolean[] front, double[] total) { int num = 0; double ffee = 0; /*boolean value = false;*/
[code]...
I have tried using the line of code commented out, /*boolean value = false;*/. However, another error is displayed. The compiler shows the following...
Inspection.java:33: error: incompatible types: boolean cannot be converted to boolean[] front[num]= defineFront(num, value); ^ Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output error...I know that boolean values are by default stored as false, once you create the array. However, I'm having trouble passing the variable to the method.
I 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)
I got the correct output here. But now I want to generalize my method into a utility class so that I can reuse the same method for setting response data directly to respective beans as given below:-
My question is how will I pass the bean object in my utility class?
public static Object getResponseData(String response,[b]String bean[/b]) throws Exception { ObjectMapper mapper = new ObjectMapper(); mapper.configure(DeserializationConfig.Feature.FAIL_ON_UNKNOWN_PROPERTIES, false); JsonNode root = mapper.readTree(response);
So I want to know how in Java you can pass a unkown type into a method (type can be an int, double, or a user defined object) and return that unkown type.
example of what I want: Java Code: public (unknowntype)[] method2 ((unknowntype)[]) //Process Data //unknowntype.process(); return (unknowntype); } mh_sh_highlight_all('java');
I know in C you can use void pointers and in c++ we have templates but I do not know how java handles this. Also I want to know if it is possible to call a method in the unknowntype.
I just kinda get stuck when it comes to passing values into constructors, using main method or static method functionality. In theory i kind of understand how it work but when i type it, it's totally different! I have to have a junit test too but i guess i could do that in the end.
I have attached the assignment. So, how to proceed with this:
public class Flight { int flight_number, capacity, number_of_seats_left; String origin, destination; String departure_time; double original_price;
currently I am doing my java web application project ,and it has following steps 1) Upload the txt files 2) java servlet gets the txt file's url , read the data and do the calculation 3) pass the results
I almost finished the second step , and working on the first step .Since there are so many input files at a given time , i have to use drag and drop method to get the file's location.how to pass file's path to servlet.( servlet code can read the data from the given txt file path )software used - tomcat and netbeans 8.0
I read in a book that when you change the value of a method parameter that's a boolean or other basic datatype within the method it only is changed within the method and remains the same outside. I want to know if there is some way for me to actually change it within the method. For example:
public class Change { void convert(boolean x, boolean y, boolean z) { //i want to set x,y, and z to false in this x = false; y = false; z = false;
[code]...
I want to put in part1, part2, and part3 when i call the method than i want them to be set to false within the method. The specific reason i asked this question was because im trying to code a battleship and i have a subroutine class with a method that when its called it checks if a ship has been sunk. If the there was a sink than the method will set a ton of boolean variables to false.
Just to clarify, I want something like this:
void convert(thing1,thing2,thing3,thing4) { //some code here that sets thing1,thing2,thing3, and thing4 to false } // than in main: boolean test1 = true; boolean test2 = true;
I am having trouble with a mouse click method. In short I have a hexagon grid, and every time I want to click on one particular hexagon I want the color of the hexagon to change to blue(by default the color is grey). This part works, but when I go to click on another hexagon I want the color of the previous hexagon to change back to grey while at the same time changing the color of the current hexagon clicked to blue. So in other words, I only want one hexagon blue at a time. How might I do this?
I have a hexagon class for one particular hexagon, and a hexmap class for multiple hexagons. I know I should probably be handling mouse clicks in the hexmap since it deals with the whole thing. But I cannot say something like hexagon.setColor within a mouselistener in that class(it gives me a lot of issues). Here is some of my code :
public class Hexagons() public Hexagons(HexMap theMap, int mapRow, int mapCol, int width, int height) { this.map = theMap; this.row = mapRow; this.col = mapCol; this.width = width; this.height = height;
Exception in thread "main" java.lang.NullPointerExceptionat DogTestDrive.main(DogTestDrive.java:19)
Here is the source
class Dog { int size; String name; void bark () { if (size < 60) { System.out.println("Woof woof");
[code]....
Some background: I'm reading "Head first Java 2nd edition" and I'm going through the examples which is showing me how to change the state of an object. The original code looks like the code below, however the previous chapter went over creating array's of an object, so I created an array of the object "Dog" and wanted to re-write it this way. To my understanding, it should work but it's giving me that error when I execute it. The error itself isn't very clear, if I could get a line number pointed to, that would work.
class Dog { int size; String name; void bark() { if (size > 60) { System.out.println(“Wooof! Wooof!”); } else if (size > 14) { System.out.println(“Ruff! Ruff!”); } else { System.out.println(“Yip! Yip!”);
I have two classes involved in this portion. CheckIn_Search
(class #1) is my main UI and I am collecting search information from the user in a jPanel form. When they click "Search" it passes the search criteria to a method that contacts a web service and gets the results. These results are passed to coSearchResults
(class #2) that opens a jFrame and jTable (in modal format, over the main window created by CheckIn_Search.
The user selects a row in the table and that selection data is passed back to coSearchResults to populate a new jPanel form. When the data is passed from coSearchResults, I want to close its window, hide the first jPanel in CheckIn_Search and make the second jPanel visible. To accomplish this, I created a method in CheckIn_Search that simply hides/shows the panels (it will do more later).
I instantiate and call the method in CoSearchResults as part of the button click event. The problem is, it doesn't work. The panels are unaffected and there are no errors. I've put in break-points and it goes into the method.. Here is the coSearch_Results code.
Here is am retrieving the jtable row id and using the first value in the row to get the data from the table model as there is more data than what is displayed in the table. I'm sending that whole row of data to the method that changes visibility.
private void btnOKActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_btnOKActionPerformed // TODO add your handling code here: int rowNum = jTable1.getSelectedRow(); String coNum = jTable1.getValueAt(rowNum,0).toString(); String[] text;
As you can see there are two listener in my xhtml file one for filetype and other for signmethod. When filtype changes signmethod has to change which in turn changes servers. And if user changes signmethod using dropdown then also server should change. But my problem is when filetype changes, both the listeners are called, as signmethod also changea but the value in event object (e.getNewValue()) is not the new one but old one. Here is the SelectView Bean.This is the static initialisation part just for checking the output at the end of question.
I am changing servers in changeServerAndSignmethod by selecting first signmethod from signmethod arraylist which is giving correct result. But changeServers is also getting fired taking wrong event object's newValue method and changing servers to wrong values. When changeServers is fired bydirectly changing signmethod, by dropdown, it gives correct result. Is there a way I can stop changeServers to fire when the change came from changing filetypes rather than direct change by user on signmethod selectOneMenu.
I am trying to pass an object of type Product p to my editProduct method, however trying to call p.getName(); doesn't work and throws a NullPointerException. The same kind of thing works for my displayRecord method (in a different class) and I can call .getName() on Product p, also passed as an argument to that method. Below is my editProduct class. The NullPointerExcepion is being thrown at line 61 (i.e., nameField.setText(p.getName());).
I don't know if I explained right, so here's a line thing of how the classes relate:
And as a side note: adding the line p = new Product(); fixes it and successfully runs the class (including the Save and Quit parts) but obviously I want it to specifically refer to the Product I pass to the method.
I'm asking a question because I don't understand how Product p could possibly be null, because the argument is passed through my DisplayRecord class, which also takes a Product p argument and works. In that class, I have declared Product prod = p; and prod is what I am passing to editProduct.
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?
