Morse Code Conversion - Variable Has Not Been Initialized
Aug 26, 2014
I'm making a program that can read an input of English or Morse code and return an output of Morse code or English back. The English-->Morse works fine, but not Morse-->English. I'm pretty sure my solution lies in displaying the variable 'morseWord', but no matter where I put it, I always get an error saying the variable has not been initialized. Here's what it looks like now:
I'm currently working on a program that is supposed to translate morse code and then display the result and I'm stuck, my program has tons of errors when I try to compile.
public class Assignment10 { public static void main ( String [] args ) { String str = Input.getString("Please type in a word"); char [] letters = {'a','b','c','d','e','f','g',
public static void main( String [] args ) { int n = Input.getInt( "Enter 1 for Morse to English, 2 for English to Morse." ); switch ( n ) {
[Code] ....
When I compile my program, I get the error message: "illegal start of expression" at my toEnglish and toMorse methods, as well as " ';' expected " at the same place.
I have some software I need to write. I am planning to write two apps for Android, one of which will send and receive Morse code, and the other to send and receive PSK31 data.
Programming is not my strong point, and I am currently struggling on how to do this. I have researched the software, and I am having a hard time finding out how to decode the audio streams on Android. I have also had difficulty finding examples and source code as what I have found is mostly written in C/C++, whereas I need examples in Java.
I'm having some trouble with getting this program to read an input of morse code and then produce an output of English. When typing in morse code for the phrase 'the string', the output looks something like this:
I am reading input from a file that has following information:
line 1 = numbers of integers in array, line 2 = elements in array1, line 3 = elements in array2.
These lines constitute a test case. There are 1000 test cases in the input file.
So basically, I read the length of arrays, populate the arrays by reading from the file.
The code is below ( I have not included reading input code):
while(test_case<1000){ if (count == 1){ //count keeps track of lines in input file vec_length = Integer.parseInt (tokenizer.nextToken()); count++; continue; } if (count == 2){ //populates array1 vector1 = new int[vec_length]; for (int i = 0; i < vector1.length; i++) vector1[i] = Integer.parseInt (tokenizer.nextToken()); count++; continue; }
Array2 is populated using the same as above code. However when I use the following code:
for (int i=0; i<vec_length; i++) temp += vector1[i]*vector2[i];
I get " local variable vector1 and vector2 have not been initialized error". But both arrays have been initialized in the if{} block. Is it because initialization was local to if block?
I know what the error means but I don't think initializing the variable will make my code work as intended so I'm having a little dilemna here... here's the code and I'll highlight the part that is said to be not initialized:
Java Code:
import java.util.Scanner; public class ItemCost { public static void main (String []args){ int i=1,item=1,e=1, f=1, g=1; int items, d ; double gst, qst, subt, Tot = 1, PriceItems ;
[Code] ....
So I'm supposed to get the following output :
Java Code:
Please input the amount of items bought 2 Please input the price of the item 1 1 Please input the price of the item 2 2 Please input the rate of GST in % 20
Please input the rate of QST in % 18 mh_sh_highlight_all('java');
HOWEVER my program doesn't seem to add input of item 1, and 2 if I initialize subt= 0 initially. It'll only take the last value inputted in the loop. By the way, the increments are counters to count the amount of errors the user might input by accident ( or whatever). Some people have been pointing it out as useless but that's the only way I found it to work.
In the following code the print method prints the default value of int(zero) for the first time even when the variable i has been assigned a value of 4. Why?
class A1{ A1() { System.out.println("Inside constructor of A1()"); print(); } void print() { System.out.println("A");
[Code] ....
Output: Inside constructor of A1() 0 Inside constructor of B1() 4
public class Test { private final int arg; private final Runnable runnable1 = new Runnable() { @Override public void run() { // No errors here, exactly as expected System.out.println("ARG: " + arg);
[Code] ....
The java compiler (version 1.8.0-b132) produces the following error when compiling this code:
"Error:(14, 46) java: variable arg might not have been initialized"
Actually, I do not expect the error here.
Both declarations 'runnable1' and 'runnable2' are essentially the same: these are just Runnable objects accessing value of the 'arg' field (which is initialized in the constructor).
The only difference between the declarations is that 'runnable1' - is an old-fashion instantiation of Runnable, whereas 'runnable2' - is an instantiation of Runnable via a lambda expression.
I want to use a try catch block, but I am not sure how to fix this problem:
int a;
try{ a = Integer.parseInt(A.getText()); } catch (Exception e){ Output1.setText("Error"); }
//do someting with a here
The purpose of the try-catch is to catch blank input.The problem with this is that underneath the try - catch I get an error saying that the variable might not have been initialized. I know why this happens. I know I could initialize the varaible before the try - catch, but there is no default or null I can set an int as. If I initialized it as 0, the blank input will no longer be catched.how to make this problem disappear?
I am trying my code which catches exception when mismatch variable is inputed as i read it with Scanner. It seems right for me but whenever i run it, it keeps leaking memory or something like that
Code :
import java.util.*; public class Exercise10_1 { static Scanner scanner = new Scanner(System.in); public static void main(String[] args) { boolean exception; do
I continuously get an error for lines 34, 36, and 37 saying that the variables may not have been initialized.
import java.util.Scanner; import java.util.Random; public class MathTutor { public static void main(String[] args) { Random r = new Random (); Scanner input = new Scanner (System.in); /*int min=1; int max=10;*/ int num1,num2,operation; int n1= r.nextInt((9+1)+1); int n2= r.nextInt((9+1)+1); operation= r.nextInt(3); int correctAnswer; int userAnswer;
class Super { static String ID = "QBANK"; } class Sub extends Super{ static { System.out.print("In Sub"); } } public class Test{ public static void main(String[] args){ System.out.println(Sub.ID); } }
According to me output should be "QBANK" In Sub...BECAUSE sub default constructor will call super() constructor.. below is the definition in jls which i am unable to understand ....
A class or interface type T will be initialized at its first active use, which occurs if:
T is a class and a method actually declared in T (rather than inherited from a superclass) is invoked.
T is a class and a constructor for class T is invoked, or T1 is an array with element type T, and an array of type T1 is created.
A non-constant field declared in T (rather than inherited from a superclass or superinterface) is used or assigned. A constant field is one that is (explicitly or implicitly) both final and static, and that is initialized with the value of a compile-time constant expression . Java specifies that a reference to a constant field must be resolved at compile time to a copy of the compile-time constant value, so uses of such a field are never active uses.
All other uses of a type are passive. A reference to a field is an active use of only the class or interface that actually declares it, even though it might be referred to through the name of a subclass, a subinterface, or a class that implements an interface.
Take a look at this screenshot... my java integrated devlopment envirnment is telling me I have a null pointer on a line with three variables ALL which were initialized.
I thought a null pointer was called when a variable doesn't get initialized.
Edit: Here is the java file and resources being used: [URL]
class GVector { // TODO: declare a private array to save the vector coordinates // Creates a mathematical vector of d dimensions, initialized at 0 public GVector(int d) { // TODO: implementation
[Code] ....
I'm confused with what type of array I need to use to save the vector coordinates and what to put in Gvector. Is it a constructor?
i have this following codes and im trying to make a java program that calls an object value initialized.
public class TestClass { public String name; public int age; public void myMessage() { System.out.println("Hello I'm" + name + "and i'm" + age + "years old"); } }
what i want is to put the following codes of the object.. so once i compile and run the project it executes the value of an object from the method i defined above.
again i am facing problem i am able to run Listener class also the ContextListener is initialised but it is giving me error on Tomcat 6.0 command prompt
Here is my Listener Class Sample.java i am able to compile the code but it is giving java.lang.nullpointer exception at runtime on Tomcat.exe Is there is problem in my code
The term "Local variable" is related to scope. That is a local variable is one which is defined in a certain block of code, and its scope is confined inside that block of code.And a "Member variable" is simple an instance variable.
I read in a discussion forum that when local variables are declared (example code below), their name reservation takes place in memory but they are not automatically initialized to anything. On the other hand, when member variables are declared, they are automatically initialized to null by default.
Java Code: public void myFunction () { int [] myInt; // A local, member variable (because "static" keyword is not there) declared } mh_sh_highlight_all('java');
So it seems that they are comparing local variables and member variables. While I think a member variable can also be be local in a block of code, isn't it?
