Is it possible to pass column name as a parameter using servlets?
I tried using the following code but it doesnt work
String date=request.getParameter("date");
String sql="alter table cs1_cn add " +date+ " boolean";
PreparedStatement ps=conn.prepareStatement(sql);
Can I pass in a return value in a parameter? I'm trying to do something like this:
Object o = new Object(anotherObject.method());
Where method returns an int. But when I try doing this it calls that method, rather than passing in the return value..
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.
View Replies View RelatedI have this class and I want to pass "pergunta" from another class:
Java Code:
here* = if I put a number, the code works. I want to receive the parameter "pergunta" here but I can't put a parameter in start .
I want to populate the array pergunta in a previous class and use in this one.
import javafx.application.Application;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javafx.scene.chart.*;
import javafx.scene.Group;
[code]....
Any way to pass parameter between try/catch block.
In other word:
I have a method:
public void invia(OiStorto invioaca) throws Exception {
Long id=0L;
try {
//some code
for (VElenpere elenpere : elenperes) {
popolaScompiute(anno, inviaEOI0, param, opempiute, elenpere,id);
[Code] ....
And finally the method in which the error can occur (the method poputa is called for every id)
private void poputa(ElOpeIncType opereIncompiute, OpeIncType operaSingola, OiOpera opere) {
try {
//some code
} catch (NullPointerException e) {
e.printStackTrace();
//return id;
}
So method invia call the method popolaScompiute, inside popolaScompiute there is an iteraction 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?
Write a method that returns the sum of all the elements in a specified column ina matrix using the following header:
Public static double sumColumn(double[][] m, int columnIndex)
Write a test program that reads a 3 by 4 matrix and displays the sum of each column.
import java.util.*;
public class SumColumns {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
final int ROW = 3;
final int COLUMN = 4;
[Code] .....
How do i make the 'date' column show only the date and 'timeIn' and 'timeOut' column only show the time. In my database table my 'date' column is a date type and 'timeIn' and 'timeOut' column is time.
View Replies View RelatedI 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.
Below is the snippet of code
public static void main(String[] args) throws Exception {
String s = "oldString";
reverse(s);
System.out.println(s); // oldString
}
public static void modifyString(String s) {
s = "newString";
System.out.println(s); // newString
}
I thought the first print statement would print "newString" as String is an object, and when we pass objects between methods, changing state of the object in any method reflects across the methods.
I'm fairly new to Java, I'm very experienced with C++ and C# in which you can pass by reference - extremely useful. Take for example this bit of code in C#:
class MyClass
{
public MyClass(int i)
{
m_i = i;
}
public int m_i;
[Code] ...
Just at the end of this program x.m_i will be equal to 8. As far as I can see this is not possible in Java: you can't pass a double by reference, using a Double will kick in the autoboxing so that won't work either. The only "solution" in Java would be to pass in a double[] (of length 1) or to make a wrapper class, both nasty solutions because a user may want to just hold a double as a member of their class just as I have, for reasons such as not allocating more memory for a class and generally not being bloated.
E.g:
onblurr="check(this, '<%=company.getId()%>' );return false;"
doing this, function check(field, inputVal) {
alert("companyId:" + inputVal);
}
Gave me the alerted value as :
companyId:<%=company.getId()%>
instead, if the company.getId() --> 30
When I do like this, how to get the value 30 inside the function? i want companyId:30
Getting JS -> JSF value to Bean class? I have tried with below code:
JSF code:
<h:commandButton styleClass="buttonpos" value="Get Value" action="#{myBean.action}" onclick="document.getElementById('crForm:hiddenInput').value">
<h:inputHidden id="hiddenInput" value="#{myBean.action}"/>
</h:commandButton>
Java Beans
public class CurrencyExchangeBean {
protected static Logger logger = ILogger.getLogger(CurrencyExchangeBean.class);
[Code] .....
So if I assigned values in arrays like the below:
This is the method in main class:
public static void trainer(){
trainer[] trainerArr = new trainer[4];
trainerArr[0] = new trainer("Ben Yap", "Male", "Kuala Lumpur", 10000, "Yoga");
trainerArr[1] = new trainer("Wilson Ting", "Male", "Kuala Lumpur", 10001, "Kick-boxing");
[Code] .....
How can i pass these arrays into another method in the main class?
i'm able to login and download pages of a website using httpclient library.but i cannot launch a page on browser after login successful!becouse the browser not remember the username and password of the session so the site show that i'm not logged!
View Replies View RelatedI am new to the JMS technology. I have written one sample sender and receiver program to pass a string message to the JMS queue and retrieve it back. It is working fine as well. But now, I want to pass a xml file to the JMS queue. Then from there I need to read the XML file and convert it into a Java object Using Jaxb. I know how to convert an XML into java object using Jaxb. But i am unable to send the XML file as a jms message to the listener.
View Replies View RelatedAs the title says, how can I pass a value from one variable to another class?
Example:
So here I'm switching one frame to another, called "redigeraProjekt". Now in this class, I want the value from .getSelectedIndex() pass over to that class. I've tried to use the variable "valIListan" but it cannot find it. Probably because it's "private" (?)
valIListan = listaAllaSpelProjekt.getSelectedIndex();
redigeraProjekt npj = new redigeraProjekt(); // "switching" to another frame
npj.setVisible(true);
this.setVisible(false);
I hope you understand what I'm saying
I'm new to Java and I'm trying to pass several values from one frame to another. I've searched around and most codes I've come across are from auto generated GUI code. This what I've been trying to do
Frame1
private class SubmitButtonListener implements ActionListener {
public void actionPerformed (ActionEvent e) {
Frame2 f2 = new Frame2();
//call setValue from Frame2
f2.setValue(4.0);
f2.setVisible(true);
}
}
Frame2
private double val;
public double getvalue()
{
return val;
}
public void setValue(double v)
[code]...
I'm taking inheritance now and some things look confusing. I'm trying to do the following but the code, in particular, the constructor in subclasses are pointed to be wrong. The constructor in LongestWord is not correct,how to pass the filename into the constructor?
Java Code:
import java.util.Scanner;
import java.io.File;
public abstract class FileProcessor {
protected Scanner input;
public FileProcessor(String filename) throws Exception
[Code] ....
Why will this NOT validate correctly in my IF Statement? Basically, a user chooses an option from the drop down list. The value is passed to t.jsp (itself) and if the option "All" is chosen, then it does something. If any of the years are chosen, then it does something else.
t.jsp (simplified version of what I want)
<%@ page import="java.sql.*" %>
<%@ page import="java.io.*" %>
<html>
<form method="get" action="t.jsp">
Select Year:
[Code] ....
how can i get id from db table for each column values with java or oracle query? i did get before each column content from file and now i need get the id of this column values from db. I read csv files from folder and then load the data from these files into subfolder, and here with line li = line.split(","); i get the values that i have in csv file and split them and become in li the value name, and then in else block i create a P objekt where i set this values from csv files, and with [I]p.setLid(li);
I set the value for all valuenames, and then get these valuenames in separate column with other content from this csv, and my question is, i need to do this with db, and write these csv file values to the table in db (it will be done with another java class), what i need, that to write the ids of these values into the table in db, instead of valuename, and while there is no ids for valuenames in csv files, i need to get the id from the table in db where these are already listed with sequences.
I don't know how can i write in data table the id of this valuenames and other content, this data table should contain the ids of valuenames timestamp values and the ids of the csv files name, i don't know how to do this with the ids, i must get the ids from the db table and then set these on [I]p.setLid(li); where i set early the valuenames, instead of valuenames i should set ids, that will set ids automatically for all these valuenames.
try {
while ((line = br.readLine()) != null) {
if (lc == 0) {
li = line.split(",");
} else {
String[] temp = line.split(",");
for (int i = 1; i < temp.length; i++) {
p = new P();
[code]....
i got the values that then will be given to [I]p.setLid(li); and iterate, but now i want to get id from the table in db where this values stored with id instead of this column values, how can i do it?
Since the array is always passed by refrence, it should have been modified, but it did not.
This is my code:
import java.util.Random;
class DiceRolling {
public void processDice() {
int [] frequency = new int [ 13 ];//frequency of every occurence of sum
[Code] ....
i want to write a program have a array 2d like that :
int array [][] = new int [3][3]
after that the user input value by using scanner then give summation of each column in matrix , i wrote this one
Java Code:
class MatrixSum{
public static void main(String[] args) {
int matrix1[][]= {{7,8,9},{1,5,2}};
int matrix2[][]= {{1,6,4},{2,7,3}};
System.out.println("Number of Row= " + matrix1.length);
System.out.println("Number of Column= " + matrix1[1].length);
int l = matrix1.length;
System.out.println("Matrix 1 : ");
for(int i = 0; i < l; i++) {
[code]...
but i want to change that the user input the value by using scanner.
I need to add a column to my array and copy an old array and then fill the new array with another array..However, unfortunately it does not work. I found this code online..but it seems it does not work.
static float[][] temperatures = new float[5][6];
static float[] d=new float[5];
float[][] neww;
int am,am1,am2,am3,res1,res2;
public static void main(String[] args) {
float[][] neww= Arrays.copyOf(temperatures, temperatures.length+1);
neww[temperatures.length]= new float[temperatures.length];
for (int i = 0; i < temperatures.length; i++) {
neww[temperatures.length][i] = Float.valueOf(d[i]);
}
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.
My code for the jsp part is below.
for (int count=0; count<list.size(); count++) {
%>
<tr>
<td> <a href="EditServlet"><%= list.get(count).id %></a>
<td> <%= list.get(count).name %>
[Code] ....
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
{
[Code].....