class Passenger{
String name;
int age;
char gender;
int weight;
public Passenger(){
[Code] ....
This is showing error.....error it gives isthat it cannot change from string type to passenger type......... How to do it??????
I have a String repersentaion of some Object.I want that object convert back into some class type how can I do this?
View Replies View RelatedI'm trying to parse and compare the content of a zip file. However I'm stuck at what SHOULD be a very simple problem, however I can't seem to find a solution. I have done the following:
ZipInputStream zin1 = new ZipInputStream(fin);
ZipEntry ze1 = null;
fin2 = new FileInputStream(fileName2);
ZipInputStream zin2 = new ZipInputStream(fin2);
ZipEntry ze2 = null;
//fin.close();
ze1 = zin1.getNextEntry();
ze2 = zin2.getNextEntry();
Which gives me the first entry of each zipfile as a ZipEntry type object. I have tried getting the path of the file (inside the zip file) and using this to create a File type object. This does not seem to work though I get:
Exception in thread "main" java.io.FileNotFoundException: My DocumentsmetadatacoreProperties.xml (The system cannot find the file specified)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileReader.<init>(Unknown Source)
And this is because I get a null return from trying to create the File file1 = new File(correctLocation);
I guess I cannot access the file inside a zip file this way. So my question is how can I make a ZipEntry type object into a File type object?
I am having a little trouble with a part of my Java assignment that needs to have linked lists in it.
I need to write a public method that takes an array of type object to load strings into a linked list.
The objective of the code is to add new records based on existing records with a partial change to the key. I'm getting "type of the expression must be an array type but it resolved to DstidArray" on dsTidRecTbl[i]
String stMajor = request.getParameter("stMajorVersion");
String stMinor = request.getParameter("stMinorVersion");
String stPatch = request.getParameter("stPatchVersion");
StringBuffer stKeySB = new StringBuffer(stMajor+stMinor+stPatch);
String stKey = new String(stKeySB.toString());
DstidArray dsTidRecTbl = new DstidArray(stKey);
request.setAttribute("dsTidRecTbl", dsTidRecTbl);
[code]....
I'm really new to object/class concepts and already having difficulties with applying them. How to create and return an array of Exam objects? I need to get a data from a textfile which is passed to the method.
Java Code:
public Exam(String firstName, String lastName, int ID, String examType, int score) {
this.firstName = firstName;
this.lastName = lastName;
this.ID = ID;
this.examType = examType;
this.score = score;
[Code] ....
I'm really new to object/class concepts and already having difficulties with applying them. how to create and return an array of Exam objects? I need to get a data from a textfile which is passed to the method.
public Exam(String firstName, String lastName, int ID, String examType, int score)
{
this.firstName = firstName;
this.lastName = lastName;
this.ID = ID;
this.examType = examType;
this.score = score;
[code]....
My GUI class:
import java.awt.FlowLayout;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.JPasswordField;
[Code] ....
Eclipse error message:
Exception in thread "main" java.lang.Error: Unresolved compilation problem:
Type mismatch: cannot convert from void to JTextField
at GUI.<init>(GUI.java:58)
at Apples.main(Apples.java:7)
I copied this from a thenewboston tutorial and he uses an old version of java but im pretty sure ive copied character for character!
I am testing some stuff here is my code:
public static void main(String[] args) {
String[] a = new String[5];
//String input = JOptionPane.showInputDialog(null, "enter input");
Scanner scanner = new Scanner(System.in);
[Code] ....
I am trying to type in 5 strings from java console and print them all out. I am using a "/" as a delimiter. My problem is that it does not print any output after I type strings separated by "/" like this: hello/gea/cae/eaf/aer and press enter. It works if I use JOptionPane but from the console its not working. I want to use the console instead of JOptionPane for this one.
I have a simple doubt
float k = 0;
k+=0.2;
k=k+0.2; // here compilation error
compliation error Type mismatch: cannot convert from double to float
My question is why not a complilation error at k+=0.2;
Below code I am using to typecast int to char.
char escapeValue = (char)0;
char cha = (char) 10;
escapeValue = (char)(escapeValue * cha); // Here am getting the above error.
I have 38 similar issues in my workspace.
If you have final int i = 1;
short s = 1;
switch(s) {
case i: System.out.println(i);
}
it runs fine. Note that the switch expression is of type short (2 bytes) and the case constant is of type int (4 bytes).My question is: Is the type irrelevant as long as the value is within the boundaries of the type of the switch expression?I have the feeling that this is true since:
byte b = 127;
final int i = 127;
switch(b) {
case i: System.out.println(i);
}
This runs fine again, but if I change the literal assigned to i to 128, which is out of range for type byte, then the compiler complains.Is it true that in the first example the short variable and in the second example the byte variable (the switch expressions) are first implicitly converted to an int and then compared with the case constants?
Got a problem with generics, which I'm still pretty new at. Here's a program that compiles fine:
import java.util.ArrayList;
import javax.swing.JComponent;
public class Experiments {
public static void main(String[] args) {
ListHolder holder = new ListHolder();
[Code] ....
It's useless, but it compiles. If I change Line 14, however, to add a generic type parameter to the ListHolder class, Line 10 no longer compiles:
import java.util.ArrayList;
import javax.swing.JComponent;
public class Experiments {
public static void main(String[] args) {
ListHolder holder = new ListHolder();
[Code] ....
I get this error:
Uncompilable source code - incompatible types: java.lang.Object cannot be converted to javax.swing.JComponent
at experiments.Experiments.main(Experiments.java:10)
Apparently, the introduction of the type parameter leaves the compiler thinking that aList is of type Object. I can cast it, like this:
JComponent c = ((ArrayList<JComponent>)holder.aList).iterator().next();
That makes the compiler happy, but why is it necessary? How does adding the (unused) type parameter to the ListHolder class end up making the compiler think the aList member of an instance of ListHolder is of type Object?
I am trying to get through JSF /PF tag for h:inputSecret but its not taking or displaying value. Please see the code snippet below
demo.xhtml
<?xml version="1.0" encoding="UTF-8"?>
<!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"
xmlns:h="http://java.sun.com/jsf/html"
[code]....
I am using JSF 2.2.
method passing null to the called function, compiler would take that parmer as what type of paramer???
View Replies View RelatedI have a Homework that's on Polymorphism and inheritance. The problem is of a triangle class. The super class is GeometricObject and the subclass Triangle. I have the parent and child classes compiling, now it's the test program.
The problem is the examples in the book don't show anything about prompting input for objects. The objects in the Triangle class are: side1, side2, and side3 and so I created objects in the test: Triangle sideOne = new Triangle(); . I've tried to compile but jGrasp doesn't like anything I do and the instructor in my class hasn't shown us examples yet. Can I prompt input for reference type and not just primitive type?
I have the following code in which I am looping through the rows of one array (composed of Strings) and copying it to another array. I am using .clone() to achieve this and it seems work as it changes the memory location of the rows themselves. I did notice that the String objects are still pointing to the same location in memory in both arrays but I won't worry about that for now, at the moment I just want to understand why the array I am cloning is not successfully assigning to the other array.
This is the incorrect line: ar[r] = maze[r].clone();
My code:
private String[][] maze = {{"*","*","*"," ","*","*","*","*","*","*"},
{"*"," ", "*"," "," "," ","*"," ","*","*"},
{"*"," ","*","*","*"," ","*"," ","*","*"},
{"*"," "," "," "," "," "," "," "," ","*"},
{"*","*","*","*","*"," ","*","*","*","*"},
{"*","*","*","*","*"," ","*","*","*","*"}};
//private String[][] mazeCopy = copyMaze(new String[6][10]);
private <T> T[][] copyMaze(T[][] ar){
for (int r = 0; r < ar.length; r++){
ar[r] = maze[r].clone();
}
return ar;
}
My compiler says: Required: T[]. Found: java.lang.String[]
Since ar[r] is an array and .clone() also returns an array why is this line incorrect.
I'm developing a JSF application.I have some enums, for example
public enum Gender {
MALE("Male"),
FEMALE("Female");
private final String label
[code]....
I want to put the enum value in <h:selectOneMenu>. I use a bean:
@Named(value = "genderBean")
@RequestScoped
public class GenderBean {
/**
* Creates a new instance of GenderBean
*/
public GenderBean() {
[code]...
How can i call the method .values() of enum for a generic enum T, like in the striked code?
I am trying to use a custom class in a .jsp page, as part of a course I am taking on Web Technologies.The original version of the jsp page was working fine, until I moved part of the Java code to a separate class.Here is the original .jsp code that is working:
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml" lang="en-GB" xml:lang="en-GB">
<%@page pageEncoding="utf-8" %>
<head>
<meta charset="UTF-8" />
<title>Forum</title>
<link rel="stylesheet" type="text/css" href="stocktails.css" />
</head>
<body>
[code]....
I am following this article : [URL] ....
It is important to note that the inference algorithm uses only invocation arguments, target types, and possibly an obvious expected return type to infer types. The inference algorithm does not use results from later in the program.
I've got an abstract class
public abstract class AbstractClass
{
//stuff
}
And a few classes that inherit from it
public class Class1 extends AbstractClass
{
//stuff
}
public class Class2 extends AbstractClass
{
//stuff
}
within another class I have a private variable with the type of the Abstract class, and within one of the methods I assign an object to the the variable like this:
public class Test
{
private AbstractClass temp;
public testMethod(){
Class1 anObject = new Class1();
temp = anObject;
}
}
Is this legal? Will temp become a Class1 object?
I have set up a project in Eclipse 3.1 and am using java 5.0 compiler.
Here's my folder structure in Eclipse
Java Code:
DFSRemoteClientTestClient.java mh_sh_highlight_all('java');
DFS is the project in Eclipse
And this is how it looks my java class
Java Code:
package RemoteClient;
import java.util.*;
// other imports
public class TestClient {
public static void main(String [] args) throws ServiceInvocationException {
// business logic here ....
}
} mh_sh_highlight_all('java');
So, basically, my java class is just a simple class with a main function.
Now when I build my project, using Project->Clean...
Then I get this as an error at the very first line where i specify the package
This is the error:
Java Code: The type Class is not generic; it cannot be parameterized with arguments <T> mh_sh_highlight_all('java');
What's this error and why am I getting this.
Here I have an enum class
public enum Money{
ONE_PENNY(1),
TWO_PENCE(2),
FIVE_PENCE(5),
TEN_PENCE(10),
TWENTY_PENCE(20),
FIFTY_PENCE(50),
ONE_POUND(100),
TWO_POUNDS(200);
private int coin;
Money(int c) {
coin = c;
}
int showCoin() {
return coin;
}
and for a test class, I need an array list with a couple of coins in it (i.e. ONE_POUND, TWO_POUNDS) and a loop that adds together the values of the coins in the list and prints the result. How can I do this?
how to get an access to the method with a parameter of class type variable, lets say: public void insert(Record newRecord, int pos)?
View Replies View RelatedSo I'm beginning to learn java with the book HeadFirst Java. The books says that all a tester class does is create objects of a new type and then use the dot operator...
I don't really understand what a tester class is and what it does ? and what is the Dot operator and how does it work ?
Suppose I have an enum class named Faction and one of the constants is named DAUNT. I created a class of the enum DAUNT but how can I pass in a DAUNT faction type in for Daunt?
Java Code:
public enum Faction {
ALMIGHTY, AMBITION, DAUNT, RESTLESS, CAN;
}
//new file
public class Daunt {
public Daunt() {
}
} mh_sh_highlight_all('java');