I am trying to make lexical phase of compiler. But when I try to add character (after validating them, whether they are character or not) to token array I cannot do it.
public class Main {
static int counter;
static char ch[];
static char c;
static char token[];
static String read;
[Code] .....
I have a question with this gui project I am building, I have gotten the code to work in very basic forms such as the main part of calculations and etc. But now I am in the phase of validation to make sure the textboxes aren't empty and are in the correct format. I have done alot research already. I would like to use a Joptionpane to warn the user of an invalid entry. But I have tried many different methods and I can't seem to get them to work.
private void calculateActionPerformed(java.awt.event.ActionEvent evt) {
double loanAmt;
int years;
boolean validData;
double rate,total,calcRate,payment,amount,numMonths,totalPayment,paymentRounded,numMonthsRounded;
[Code] .....
When ran I get these errors: (only copied a few of the main lines)
Exception in thread "AWT-EventQueue-0" java.lang.NumberFormatException: For input string: "p"
at sun.misc.FloatingDecimal.readJavaFormatString(FloatingDecimal.java:1241)
at java.lang.Double.parseDouble(Double.java:540)
at car.loan.NewJFrameCarloan.calculateActionPerformed(NewJFrameCarloan.java:228)
at car.loan.NewJFrameCarloan.access$500(NewJFrameCarloan.java:17)
at car.loan.NewJFrameCarloan$6.actionPerformed(NewJFrameCarloan.java:106)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2018)
I have a problem with my code. It gives me the error I put as title:
backgroundA.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
if (j < 2){
int randomInt1 = random1.nextInt(Deck.length());
int drawableIDA = Deck.getResourceId(randomInt1, -1);
[Code] ....
This error is in the first line and I have also one in the last, where eclipse looking for a @ (O.o). Also I will insert the variable choice1.
final Button choice1 = (Button) findViewById(R.id.A);
I have a problem with my code. It gives me the error I put as title:
backgroundA.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
if (j < 2){
[Code]...
This error is in the first line and I have also one in the last, where eclipse looking for a @ (O.o). Also I will insert the variable choice1.
final Button choice1 = (Button) findViewById(R.id.A);
how do i get the inputed strings to print out after i turn them into tokens ? I need it to ask for a number and then multiple lines of strings, turn them into tokens, then print them out.
import java.util.*;
public class TokenDriver{
public static void main(String [] args){
// TokenStore words = new TokenStore();
String[] tokens = new String[300];
[code].....
also as a follow up how would use an array in an other class (TokenStore) to save the typed line information
I am trying to read a text file into Java and split the text into tokens. Eventually I want to be able to count the number of instances of a specific word. However, at this point, when I run the file, all I get is the location of the file rather than the text in the file.
import java.util.*;
import java.io.*;
public class textTest3 {
/**
* Prints the number of words in a given file
*
* @param args
* @throws IOException
*/
[Code]...
I am reading a java book and find a theory about Interpreter and Compiler. explain different between them?
View Replies View RelatedAn example from the SCJP(OCP) book:
Java Code:
class Animal {
void makeNoise() {System.out.println("generic noise"); }
}
class Dog extends Animal {
void makeNoise() {System.out.println("bark"); }
void playDead() { System.out.println("roll over"); }
[Code] .....
The book states that the above code will compile if there is a downcast in the line 14 . But there is a compiler error saying playDead method is not defined for type animal even after downcasting.
Running a java source code through an online java compiler (in which you will just pass the the source code using a http request, then the compiler will return the output/error of the source code automatically)?.
View Replies View RelatedI am working in software testing, specifically automatic test cases generation. Among the existing forms of test cases, my focus is on the test cases that are composed of sequences of events such as _.event1.event2 eventx()
However, the events can be classified into: sensitive and insensitive. The latter does not affect the system's states, and hence, it can be ignored; while the former affects the states. Anyhow, the sensitive events in the test cases may lead to states explosion and there is a need to prevent that. Therefore, some techniques suggest using one variable to present states and group all similar states together such as using len variable in circular queue. Relatively, the states can be represented by using specific drawings such FSM.
For example, the test cases for circular queue may look like:
add(0).remove().add(1).Front()
add(0).add(1).remove().Front()
which produce the following states:
len=1, rear=0, front=0 and dataQ[0]=0
len=0, rear=0, front=1 and dataQ={0}
len=1, rear=1, front=1 and dataQ[1]=1
len=1, rear=0, front=0 and dataQ[0]=0
len=2, rear=1, front=0 and dataQ[1]=1
len=1, rear=1, front=1 and dataQ={1,0}
As can be seen, every addition/deletion produces a new state. A state is composed of 4 variables: len, rear, front and dataQ. The 1st three variables are integers while the dataQ is an integer array. Nonetheless, the states produced by different test cases can be identical which wastes effort and time. So, there is a need to optimize these states. The search techniques were suggested where the problem can be represented as a search problem and the technique is applied. If we consider Len as a state, then we will have: len=0; 0QSize. However, this does not represent the state but it suits for classifying the states into groups.
In terms of states representation, State Machine/Map Compiler (SMC) was suggested as a modeling mechanism that takes the state machines (i.e. FSM) drawing and generates the code in any preferred language. In SMC, the FSM is represented in a specific syntax (state---transition----next state) and saved in a file (.sm). This file will be compiled by SMC to generate a context class which includes definitions of states, transitions and actions in FSM but still need to be triggered by another class. This class has to call the transitions that modifies the state.
We had created that class and implemented all the methods with their transitions. However, the FSM used was based on 1 variable only (i.e. len). Besides, we are still looking for the SMC results as they will be the input for any search technique to be applied. Supposedly, the states generated by SMC can be used directly in the search technique but this is still questionable.
I have started to learn JAVA and was referring Head First JAVA book.
I have 3 separate .java files - GuessGame.java , Player.java, GameLauncher.java
I have successfully compiled GuessGame.java & Player.java
But I am getting an error when I am compiling GameLauncher.java.
I remember reading Instance variables & local variables (in methods) are initialized to appropriate value by the compiler.
Is this true for static class variables and variables in nested classes ?
public class Main {
private static void foo(Integer a) {
System.out.println("Integer");
}
private static void foo(long a) {
System.out.println("long");
[Code] ....
This code prints long. Why is that? How did compiler decided that it likes long version of foo() method the most. If I had to guess I'd pick int... or possibly Integer as they are most similiar to what was passed. But why long?
I'm a beginner fiddling around classes in Java. I noticed on this particular code, Eclipse will give me an error and suggest I put the static keyword in front of the variable.
public class test {
//the following line is where Eclipse puts the static keyword
static FileAccess hello = new FileAccess("D:" + '\', ".mp3");
public static void main(String[] args) {
for (int i = 0; i < hello.getTotalNumberOfFiles(); i++) {
[Code] .....
The FileAccess class is just a class I made while trying to retrieve filenames from my hard drive.
As far as I can tell, it works correctly after I put the static keyword there. I just want to know why it is required in this particular code, considering it didn't need to do that when I made a simpler class while I was getting my feet wet at creating classes in Java.
public void init(Board board) {
JPanel Panel = new JPanel();
Panel.setLayout(new GridLayout(board.getWidth(), board.getHeight()));
getContentPane().add(Panel, BorderLayout.CENTER);
Panel.setBorder(new LineBorder(Color.BLACK)); // it does not work also
[code]....
I have a JFrame. I added two JPanels to the JFrame. The first one is GridLayout and it should be situated at CENTER. Another one is bottomPanel, and that one should be situated at SOUTH.I would like to add two new JPanels(kit and another one) to the bottomPanel.Compiler does not show any warning or errors.The problem is, that bottomPanel situates at NORTH, not at SOUTH. kit situates at CENTER of bottomPanel, not at WEST.
I was trying to execute the following codes, but the something that I don't undestand was happen. The program was compiled differently according to ouput picture of the program in my java book. Furthermore, then I tried to compile the program in eclipse and NetBeans. I saw that all of output are different each other.
package finallyblock;
public class FinallyBlock {
public static void main(String[] args) {
try{
throwException();
}
catch(Exception exception){
System.err.println("Exception handled in main");
[code]...
Is there any way to compile a program without calling constructor.
View Replies View RelatedMy objective here is to process a HashMap's key's in order. I found SortedSet as a way to do it.
The HashMap is like this:
nobelPrizeWinners = new HashMap<String, PrizeWinner[]>();
// 2009:
nobelPrizeWinners.put(new String ("2009 Physics"), new PrizeWinner[] {new PrizeWinner("Charles K.", "Kao"), new PrizeWinner("Willard S.", "Boyle"), new PrizeWinner("George S.", "Smith")});
[Code] ....
This is the method I am trying to write
public void displayAllYearsAndWinners_2()
{
// Creation of the SortedSet
SortedSet sortedSet = new TreeSet();
[Code] ....
However, the compiler gives me a warning of NobelPrizeWinners.java uses unchecked or unsafe operations. Recompile with -Xlint:unchecked for details.
As I said, my objective here is to process them in order. If this compiler warning cannot be resolved, I am open to other methods of accomplishing my objective.
I need to do a simulation on the assembly code level by writing a mini-compiler for each ISA, i.e., 4, 3, 2-Address Architecture, Accumulator Architecture, Stack Architecture, and Load-Store Architecture.The input to the simulator is a segment of C program:The basic sample segments of C code are:
1. A = (B + C) * D - E;
2. F = (G + H) - (I + J);
3. G = H + A[I];
4. If (I == J) F = G + H;
Else F = G - H;
5. Loop: G = G + A[I];
I = I + J;
If (I != H) Goto Loop;
6. If (G < H) Goto Less;
7. While (save[I] == K)
I = I + J;
So I'm trying to implement a quick sort method for an ArrayList of Strings and right now I'm getting the compiler error message: Exception in thread "main" java.lang.OutOfMemoryError: Java heap space. I don't know what that error means nor how to fix it. I've marked in my code where the error seems to be occurring.
import java.util.ArrayList;
public class quickSort
{
// constructor
public quickSort()
[code]....
what is the use of checked exception.I know unchecked exception or Runtime exception are thrown by jvm whenever programmer makes any mistake in logic and current thread is terminated.But checked Exception are checked at compile time so that compiler compels programmer to put risky methods in try catch clause. And this checked Exception are caused due to problem in IO operation or any such operation which the programmer can't control.Programmer can't do anything to avoid this checked exception but can catch this exception.
Now the question is Why compiler compels checked exception to be put in try catch clause but doesn't complain anything in case of Runtime Exception???
A java program to print 10 random numbers between 512 and 1024 and then finds the smallest and biggest numbers from the list using only one loop
class BSLab4d {
public static void main (String[] args){
int[] nums = new int[10];
int largest = nums[0];
int x = 0;
int smallest = nums[0];
int y = 0;
[code]....
I am using a static method to convert a string to an Integer object. Next using a instance method to convert Integer object to an int.
Compiler is giving me two "cannot find symbol" errors:
One pointing to the dot operator between "Integer.valueOf(s)"
The other pointing to the dot operator between "obj.intValue()"
I have latest JDK installed: jdk-7u51-windows-x64.exe
Looks like JCL installed correctly with rt.jar file located in "lib" directory under "Program Files"
Following is source code:
Java Code:
public class StringToInt
{
public static void main (String args [])
{
String s = "125";
Integer obj = Integer.valueOf(s);
int i = obj.intValue();
i += 10;
System.out.println(i);
}
} mh_sh_highlight_all('java');
We are making a tic tac toe game for my CS120 class and I am having trouble figuring out how to make our X's and O's. Is there a way to make shapes besides making two lines for an X and an oval with a white smaller oval inside to make an O? We have only learned the basics so far in class (i.e. events, inheritance, client-supplier, etc.)
These are our instructions:
Write a controller that controls the game. There is one human player (the X player) and the computer player (the O player). The name of the class must be TicTacToeController. In a sense, the controller is the game since the controller will 1) create a TicTacToeModel 2) create a TicTacToeView and 3) create a TicTacToeButton (you must write this class following the design pattern covered in class lectures), a label, and text field such that when the button is pushed, the player moves into the cell selected by the text field. After every player move, the computer moves into a randomly selected empty cell. When the game is over, a text message must be displayed somewhere on the screen the gives the status of the game. While you are free to change the appearance of the controller, the basic elements must be provided (a view of the game, a button, and a text field to enter the cell). A sample screenshot is displayed below.And this is the code i have thus far:
[import java.awt.*;
import javax.swing.JFrame;
public class TicTacToeView extends Rectangle
public TicTacToeView(int x, int y, int w, int h) {
super(50,60,w,h);
this.setBackground(Color.red);
JFrame win = new JFrame("Tic Tac Toe");
win.setBounds(10,10,w+100, h+100);
win.setLayout(null);
win.setVisible(true);
win.setBackground(Color.gray);
[code]....
I want to ask how to make Palindrome in Java with 2 methods //Output is Like this
Input a word
Hey
Not a Palindrome
Reverse
yeH
I am stuck. I was trying to make my own Color to use with awt.
I used the statement :
public static final Color purple = new Color(255,0,255);
When I try to use Color.purple it says it cannot reference purple.