I'm new to Java and am trying to work through some questions where I have to convert a UML diagram to Java code: I have an image of the uml document-
http://s1079.photobucket.com/albums/w513/user20121/?action=view¤t=uml.jpg
I'll show you what I have so far:
Q1: Write a Java version of class Entry assuming it has this constructor: public Entry(String name) and that the method getSize is abstract. A:
public abstract class Entry {
private String name;
public Entry(String name){
this.name = name;
}
public String getName()
{
return name;
}
abstract long getSize();
}
Q2: Write a Java version of class File assuming it has this constructor: public File(String name, long size) A:
public class File extends Entry {
private long size;
public File(String name, long size){
super(name);
this.size = size;
}
public long getSize(){
return size;
}
}
Q3: A directory contains a collection of files and directories. Write a Java version of class Directory assuming it has this constructor: public Directory(String name) and the method getSize returns the total size of all the files in the directory and all its sub-directories (in this model the size of a directory itself is ignored).
A: This is where I get stuck, I don't know what to do about the getSize method. Can anyone tell me whether what I have done so far is correct? And also point me in the right direction for Q3?
Edit: okay I have attempted an answer but I really I don't know what I'm doing..
import java.util.ArrayList;
public class Directory extends Entry {
ArrayList <Entry> entries = new ArrayList<Entry>();
public Directory(String name)
{
super(name);
}
public long getSize(){
long size;
for(int i=0;i<entries.size();i++)
{
size += //don't know what to put here?
}
return size;
}
}
for(Entry entry: entries) { ... }
Within the brackets 'entry' is the Entry object of the current iteration, whose methods you can call normally:String name = entry.getName();