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Java cannot find class within same package
I've written a class object, QueueObject, but when I try to construct it inside of my main class, it says it cannot find the symbol on compilation. I've read lots of pages saying how misspellings or import failures could cause it but both files are in the same package and I double checked spelling although I think Eclipse would tell me if I spelled QueueObject wrong.
QueueObject.java
package disksim;
public class QueueObject {
//The total time the object has been inside the queue for
private double time;
//The objects position, 0 >= x <= 1023
private int id;
public QueueObject(int id) {
this.time = 0.0;
this.id = id;
}
public int getId() {
return id;
}
public double getTime() {
return time;
}
public void setTime(double time) {
this.time = time;
}
public void addTime(double time) {
this.time += time;
}
}
MainClass.java
package disksim;
public class MainClass {
private static String algore;
private static int Qsize;
private static String filePath;
private static ArrayList<QueueObject> queue = new
ArrayList<QueueObject>(Qsize);
public static void doFIFO() {
File data = new File(filePath);
try {
Scanner in = new Scanner(data);
while (in.hasNextLine()) {
if (queue.size() != Qsize) {
queue.add(new QueueObject(Integer.parseInt(in.nextLine())));
}
}
System.out.println(queue.toString());
in.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Compilation Errors
1 answer
eclipse has a built-in compiler. When developping in eclipse (or any other Java IDE), you can run from eclipse, you can package as a JAR file from eclipse, and even run a full fledged maven / gradle build from eclipse. There is no need to ever run javac by hand when you have a Java IDE.
One reason nobody in their right mind uses javac by hand is that it is notoriously picky about directories. In particular, it expects to be invoked in the root source directory, not any subdirectory thereof. So when you write:
I compiled it from the folder that both files were inside of
you are doing it wrong. The correct file layout for Java source files looks like this:
<source root directory> <-- working directory for invoking javac, can have any name
com <-- source files for package com
codidact <-- source files for package com.codidact
software <-- source files for package com.codidact.software
Main.java
Queue.java
(to avoid name conflicts, it is customary to name packages using a reversed domain name under your control, so if codidact were to write Java code, they might use the package name com.codidact.software)
In your case, that looks like this:
<source root directory> <-- working directory for invoking javac, can have any name
disksim <-- source files for package disksim
MainClass.java
QueueObject.java
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