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've downloaded the Windows version of Java Commnunication API from java.sun.com. I extracted the zip file, placed the comm.jar at c:j2sdk1.4.0jrelibext folder.After that, i wrote a simple program to test whether i can get any serial/parallel port object from CommPortIdentifier.getPortIdentifiers();. It returns an empty enumeration, meaning that none of my ports are detected.
However I have checked that com1 port is exist using hyperterminal. I have RFID card reader and I am trying to read data from rfid card.
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 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.
I am trying to run an example in which I pass a parameter to imported file but its not working.
This is my header.jspf file which I will include in a jsp file.
<img > <br>${param.sub}
And This is the JSP file contact.jsp
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <html> <body> <c:import url="header.jspf"> <c:param name="sub" value="We love to hear from our clients------------" /> </c:import> <br><br>
Now this is JSP page content
</body> </html>
When I hit the contact.jsp file , It does show me the image I have on header.jspf , but its not able to print the parameter that I am setting in <c:param>
So after showing image it just shows ${param.sub}. So EL is not translated properly.
So, this is weird for me because I don't really understand why the BorderLayout class constructor is being initialized as a parameter for the setLayout..
I have multiple Java classes that holds lots of time based parameters, e.g.: (simplified):
Java Code: class Engine { float rpm; boolean enabled; int runningTime;
[code]....
Is there any simply solution to map all these parameters from my TimeRecord to one list(vector,map) of params that user can choose from and see the value in proper form (floating type, boolean type) ?
I just want that user can pick a paremter's name from list or combobox and choose parameter that he wants to see. I don't want to duplicate the data - just some kind of mapping algorithm between list of parameters names and my TimeRecord. eg. some collection class that holds all names and connections: Parameters params; fill combo/list from this class for ( String name : params ) { combo.add(name);}, then when user picks some field from combo: params.getValue( myTimeRecord, name ) return correct parameter value (just my first thought)
Later, I want to replace all floats,ints,booleans with some kind of templated class eg. Value which will hold all kinds of measurement unit with conversion support - but it's only a plan now.
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.
Now, i have an array of Client, so I would like to enter within this. Example:
public void addClient(Client c){ for (int i = 0; i<client.length ; i++) { // client is an array of Client object client[i] = c; // Enter a c in the array, but does not work! System.out.println("test "+clienti[i]); // print Client@15db9743 } }
I have used the println for check if worked insertion, but the result shows no
